Charger no chargey on house power

[randys006]

Hi all, I've had the rig for about 4 months now, and I'm a first-time poster. I can't get my charger to work on house power. I say house power because it does charge when the genny is running, and it also did charge the last time I was hooked up to 50A service at a resort. The charger just won't turn on, e.g. the 'charger' LED on the remote never lights up, and the remote display says 'inverting.' I'm parked for a while and I need to quit running the genny because A) diesel is too expensive and B) while the neighbors haven't complained yet, I imagine it's a bit annoying.

I'm savvy with electricity and electronics in general, but pretty new to RV stuff, particularly fancy inverter/chargers like this. I've read a few posts and done a bit of debugging, but first the basics:

Magnum S2812
Inverter version 5.9
Remote version 1.2
(2) 12V AGM chassis batteries, replaced 2 weeks ago
(4) 12V AGM house batteries, age uncertain but seem to hold up pretty well
The coach is equipped with "battery boost" which allows the house batteries to charge up and deliver cranking amps to the chassis batteries. It's operated by a switch on the driver console. I would guess the switch just engages a relay, but it may be more complex than that.
Residential refer, old one without any "economy mode." The base constant draw is 300-400W.
I do have solar panels but they're original/ancient/useless. The best supply I've seen is about 100W.

I have two power sources at the house:

1) good-ole 20A (non-GFCI). I've probed my adapter with a meter and verified that both hot legs have >120V. I tried many charger settings, including all shore max settings (as low as 5A), all charge rate settings (as low as 10%). I can see these affect the charging amps with the genny running, but the charger never turns on.

2) solar panel array. We don't have batteries, so they're only active on sunny days. It basically feeds the house and has a 220 RV pick-off. The pick-off says 23A max, and I've seen close to that going to the house, so the system seems to be working well. I won't be running ACs etc--just keeping the batteries up. I measure 122V at each hot leg and 244V hot-to-hot, but I don't have a way to measure the current. The controller was for the previous owner's Tesla charger..we don't own a Tesla. We're waiting to hear from him to see if anything else needs to be done for RV hookup.

Now for testing: I've done a couple factory resets on the inverter with no change. Checked every fuse (that I can find) and toggled every breaker multiple times. I've seen people mention a 250A fuse in the battery cable. I've looked about everywhere and can't find that, but it can't be that because it does charge on other sources...right? Pored through the manuals and studied schematics on multiple occasions, once until I literally fell asleep haha.

I had a pretty good electrical storm a couple months ago so it's possible something got zapped...but I'm pretty sure I have seen it charge on shore power since then. It just seems like there's a setting or a switch that got flipped that I can't find. It's funny, but I'm really hoping for the "idiot user" result here, lol. Any ideas?

Thanks y'all!

 

[96 EVO]

Sounds like you've covered about everything!

I'm assuming you have pressed the 30A-20A button on the Magnum remote panel?

[Martinvz]

Randy, Welcome to the group.

Try the following: on the inverter are 2 push-in circuit breakers. Make sure these are in. Check if this solves the issue. 
If still unresolved, try resetting the inverter. On the one side you should find an on/off switch. Turn it off, wait a minute and then turn it on. Check again.

These are the first things to check. Ic it is still not charging then let us know. 

[Just Jim]

Have you tried checking at the house batteries to see if current is actually going to them while plugged in?  "inverting" is converting 12 v to 110 v, so that should not be displayed while plugged in as that is an indication you are just running on battery.  Might check the transfer switch.  Generally the genset is primary even when plugged in to shore power, so the batteries will not charge from shore while the genset is running.... but should switch (transfer) when the genset is shut down.  Its possible that 20 amp circuit is not enough to charge the batteries, but I've never had that problem.  Someone here will be able to help more.

[96 EVO]

Are you using decent quality 50-30 and 30-20A dogbones?

[Guest Ray Davis]

1 hour ago, randys006 said:

122V at each hot leg and 244V hot-to-hot

This concerns me since you mentioned a good-ole 20A (non-GFCI).   Where are you getting 240 volts from,  the generator or the 20A receptacle?

[Tom Cherry]

1 hour ago, randys006 said:

Hi all, I've had the rig for about 4 months now, and I'm a first-time poster. I can't get my charger to work on house power. I say house power because it does charge when the genny is running, and it also did charge the last time I was hooked up to 50A service at a resort. The charger just won't turn on, e.g. the 'charger' LED on the remote never lights up, and the remote display says 'inverting.' I'm parked for a while and I need to quit running the genny because A) diesel is too expensive and B) while the neighbors haven't complained yet, I imagine it's a bit annoying.

I'm savvy with electricity and electronics in general, but pretty new to RV stuff, particularly fancy inverter/chargers like this. I've read a few posts and done a bit of debugging, but first the basics:

Magnum S2812
Inverter version 5.9
Remote version 1.2
(2) 12V AGM chassis batteries, replaced 2 weeks ago
(4) 12V AGM house batteries, age uncertain but seem to hold up pretty well
The coach is equipped with "battery boost" which allows the house batteries to charge up and deliver cranking amps to the chassis batteries. It's operated by a switch on the driver console. I would guess the switch just engages a relay, but it may be more complex than that.
Residential refer, old one without any "economy mode." The base constant draw is 300-400W.
I do have solar panels but they're original/ancient/useless. The best supply I've seen is about 100W.

I have two power sources at the house:

1) good-ole 20A (non-GFCI). I've probed my adapter with a meter and verified that both hot legs have >120V. I tried many charger settings, including all shore max settings (as low as 5A), all charge rate settings (as low as 10%). I can see these affect the charging amps with the genny running, but the charger never turns on.

2) solar panel array. We don't have batteries, so they're only active on sunny days. It basically feeds the house and has a 220 RV pick-off. The pick-off says 23A max, and I've seen close to that going to the house, so the system seems to be working well. I won't be running ACs etc--just keeping the batteries up. I measure 122V at each hot leg and 244V hot-to-hot, but I don't have a way to measure the current. The controller was for the previous owner's Tesla charger..we don't own a Tesla. We're waiting to hear from him to see if anything else needs to be done for RV hookup.

Now for testing: I've done a couple factory resets on the inverter with no change. Checked every fuse (that I can find) and toggled every breaker multiple times. I've seen people mention a 250A fuse in the battery cable. I've looked about everywhere and can't find that, but it can't be that because it does charge on other sources...right? Pored through the manuals and studied schematics on multiple occasions, once until I literally fell asleep haha.

I had a pretty good electrical storm a couple months ago so it's possible something got zapped...but I'm pretty sure I have seen it charge on shore power since then. It just seems like there's a setting or a switch that got flipped that I can't find. It's funny, but I'm really hoping for the "idiot user" result here, lol. Any ideas?

Thanks y'all!

 

Whilst typing this....three folks replied.  Good comments....and good advice....but I have a different take....especially from all the info you gave....OK....from the top....you MAY not really have an issue.....but I need to make sure I understand.  Also, I have attaching two files for your review.  The first one is the basics...  OMG, how do I set up my Magnum and the second is a troubleshooting guide...  You can ALSO call Magnum and they will help....but, here is my take....ALSO understand that this will be basic as many members have commented that when "Monaco Electrical 101" is taught, they learn and does NOT reflect on your expertise....but we try to keep it elementary or until you can comment on your trouble shooting ability.

First...  start with the SHORE.  Set that for 20 Amps.  That setting is based on the "protection" for the feed. When you are on Genny or 50 Amp Shore....that setting should be 30 Amps.  The reason....the 30 amp breaker(s) in you main (you probably have a Dual In-Dual out Inverter setup) and you probably have a Main panel with the two 30's and a sub panel with additional breakers and at least one or maybe 2 GFCI's...  SO, just be aware...Genny or SHORE...30 and Other, say a NON GFCI 20, use 20. NOW as long as the MH does NOT trip the breaker for the 20A, all is well....if it does, downrate it to 15.  This is exactly what Magnum says....verbatim.

Next.  Look at the Setup.  There are a couple of KEY's here.  ONE....use the AGM2 setting or profile.  You don't have the optional 8 battery bank which was typically standard for a factory Res Refer....doesn't matter....you have 440 to 450 Amp Hours of capacity.  The AGM's may be slightly lower....so just look at them and multiply times TWO.  Since two are in Series.....the amp hours are the same....so when you put TWO batteries, in series.....and then have TWO sets of TWO...bingo, the current is doubled.  Whatever you have, use the "Range Setting" when you set up the battery profiles.  Typically turn the first setting....SEARCH WATTS to OFF or DISABLED.

NOW....the real cruz of my thoughts. SO....bear with me.

FIRST....you have, I assume, all internal power to the house outlets and also to the Microwave and to the Res Refer.  I mean that while you are on the 20 Amp pigtail....that you have ALL internal power...  IF SO....then forget BREAKERS and FORGET the Pin Breakers.  The Magnum is "transferring power" from the 20 amp to the Main panel.  That also means that your 4 "AGM's....condition unknown" are good enough for the Magnum.  By that, I mean that there is an Automatic Transfer Switch in the Magnum.  IF you have SHORE (120 or 30 Amp or 50 Amp or Genny) power, then the Magnum is measuring it.  BUT the Magnum is persnickety and will bite your bottom if you "try to cheat".  OK, pardon my humor...but anyone that uses CHARGEY ....  So, if there were NOT a reasonable set of batteries, as in, they will take a Charge....then the Magnum cuts off the AC power or does NOT let the ATS (internal) pass through the power.  SO, that tells me....the Batteries may not be GREAT or Excellent...but THEY DO have voltage and the Magnum's Battery Sensing circuit, which controls the ATS is good.

OK....then....that leads us to.   WHAT IS THE LOAD inside the Motor Home.  You said, you do NOT have a clamp on Ammeter.  OK....lets not stress....do it the OLD fashioned way.  

First go to the SETUP on the Magnum.  That is step five....if my chart is right.  Set that to say 20%.  OK....then try this.  Turn OFF all the breakers in the SUB PANEL.  NOT THE MAIN PANEL.  These breakers in the Sub Panel are for the PASS Through or INVERTED power or voltage.  HERE is the "science" behind this and the logic and the calculations.  FIRST....you have 20 Amps of POWER....120 VAC.  Multiply 20 X 120.  You get 2400 WATTS (Volts X Amps = Watts).  NOW....the Charger (in the Inverter) is gonna try to HIT the Batteries with up to 14.8 or even higher....DC.  SO, you have a potential of 2400 Watts....  TECHNICALLY, to make my old EE prof happy, the Inverter/Charger is only 95% effiecent...or it SKIMS off the 5%.  SO 2400 X .95 equals 2280.  OK....we are in DC now...so that 2280 Watts has to be DIVIDED by 14.8.  The ANSWER is 154 Amps....so you could FULLY CHARGE...at 100% Charging RATE....your batteries.....  BUT, if you have ANY OTHER load....as in the Res Refer or the Microwave or whatever.....then the Magnum cuts back...

NOW stay with me.  When the Magnum is set at 100% charge rate....it takes its BEST SHOT....as in it will pump or show 100 AMPS.  BUT, if the power source, as in the REDUCED Amperage, with my fudge factors, can't support that....it says....NOPE.. AIN"T GONNA CHARGE.  YES, that IS the logic.  The Magnum knows how much power is being supplies and used and what it needs to charge.  SO, set your charging rate too HIGH for the Line Amperage as well as the NORMAL LOAD....if it comes up SHORT....the charger stays OFF.

SO, we ELIMINATE all the AC LOAD.  We also turn DOWN the charging rate.  If my guesses and "experience" are right....you will see the charger come ON....but it will NOT be pulling the 100 Amps.....we throttled that back to 20%....so I would expect it to be lower..  NOW....if that works....lets go back into SETUP....Scroll or Navigate to Step 5....set it for 50%.  BINGO....the Amps should increase.  IF, IN THEORY, you would go to 100%, then you would see the 100 amps....but BEAR IN MIND....you only, theoretically have 154 Amps of DC...

NOW....that would be the simple way to test...  You have NOT commented on the lack of INTERNAL power as the outlets are DEAD or the Microwave ain't flashing.  SO....by killing the internal load....the Magnum can fully utilize the FULL 20 Amps....and it only needs about 15 Amps.

OK.....Ben (EVO 96) just chimed in....so there are FOUR posts....  Ben makes a GOOD point.  The 30 to 50 Dogbones are NOTORIOUS for being "worn out" as in the connections (inside the molded) plugs will open up or folks will overload them....and they have a HIGH resistance connection.  Same for the simple 30 to an AC plug.  IF you have a BAD DOG BONE, either ONE, then that could be part of the issue....

SO, Thanks to Ben, my TWO top choices....the internal load is too high and the charging rate is set too high and the load is dropping the 20 amps down to an "Available to CHARGE" way below the needed 15 Amps for the 100% setting.  Kill the load.  Throttle back the charging rate and ramp up a bit....if your charger works....then ALL IS WELL.

Ben's point is the second....like A1 and A2...  

FINALLY, since the Charger works on Genny....my "gut...and Magnum also" tells me that all is well and you have either a high resistance point or source in your dog boned down line....or the Magnum is set WAY too high and there is the load of the Res Refer and such and the Magnum is in the "I ain't GONNA Charge" mode....the solution....  Drop the HOUSE (turn off the breakers in the sub panel) and then ramp up the charging rate....  IF THAT FAILS....probably a BAD dog bone.

OK....that's the simple answer....fiddling around and doing resets and such....NOPE.  It worked at a 50 Amp resort....it works on a 50 Amp Genny.  AS LONG as you have INTERNAL power (the Outlets, Res Refer and Microwave), the MAIN ATS is switching and working.

NOW......as to your SOLAR....  WOW....that is interesting.  I DO haver a little bit of background helping friends out with how to charge their EV's...  What I DON'T understand....  and this is how most do it.

Tesla offers a "Wall Connector".  Depending on the model....the line (cable size) could go up to 65 Amps.  Lower ends can be smaller.  The Wall Connector is nothing more than a GLORIFIED "OUTLET".  It is a SPECIAL configuration....  Pull off the Wall Connector.  FOUR WIRES.  RED & BLACK are HOT.  White is Neutral...and BARE or GREEN is ground.  If your home has a standard BREAKER marked "EV" or whatever....then as LONG as it is 50 Amps or above....and you have the TESLA Wall Connector....you can have it "Disconnected" and put a 50 Amp service there....that will feed your RV.  NOW....that is the simple way.  If there is some sort of booster or Solar....then ALL BETS ARE OFF.  BUT, most of the Tesla's have 240 VAC (yes...a MH Pedestal is 240 VAC...you just do NOT have any 240 VAC devices).  SO, a 50 Amp Breaker on a main house panel going to a Wall Connector is what MOST have...and if there is a "Solar backup" or boost....then if the 50 Amp service is there....you got 50 Amps.  BUT, if the solar has control of the circuit....as in...."we ain't gonna use any HOUSE or GRID POWER" only Solar....then a qualified electrician who understands the "ins and outs" of the solar and how the controller works....will be necessary....BUT....MARK MY WORD...if you can plug in a TESLA Connector....not a 120 VAC adapter...then there is a TESLA WALL CONNECTOR.....They make money on them.

SO....I would NOT stress over the Solar and Tesla until you get more information.  Maybe you lucked out....there is, for nighttime charging, a 65 or at least a 50 Amp "EV CIRCUIT BREAKER" in your main house panel....then you have the wiring for a standard RV 50 A receptacle.  BUT, if MR. Solar is calling the shots....then trying to run your MH will NOT be cool or will be ugly.  You can NOT run all the stuff on a 30 Amp (240 circuit....)....it takes a FULL 50....  As a Moderator, I am asking that we sort of PASS on this until we fix your issues.

BY THE WAY....again, for your EDUCATION.  YES, you do have BIRD or Bi-Directional charging...in that when you DRIVE....the House gets Charged.  When you are on shore (30 works or so will 20....but flaky), you will be charging the Chassis.  NOW....if you Chassis batteries are down a bit...but not dead, then the charger is gonna try to charge them.  That DOES put a strain on the system.  IF you want to experiment.....and THIS IS PURE conjecture...  TURN OFF the Chassis BATTERIES.  That will, I KNOW....100% guaranteed...STOP the BIRD or Bi-Directional charging.  SO, now to make it a little complicated....  There is a fancy Board....Board #6 in the REAR RUN BAY.  That BOARD has to be powered from the HOUSE and the CHASSIS bank to work....or give you BIRD or TWO WAY CHARGING.  That board....is also where the BOOST SWITCH up front is wired to.  The BIG BOY or the big solenoid gets its marching (as in signal) from Board #6.  The BOOST, may work to allow you to tie the two banks together for starting.....fuzzy on that.  BUT, if you are in the BIRD MODE or CHARGING BOTH BANKS....that adds a strain to the Magnum.  TURN OFF the CHASSIS....if all the above doesn't work.

YES....unfortunately, these systems ARE this complex....but as you learn MORE about Electric circuits and how the work....then the "easier" to troubleshoot.  Right now...  I'm working on 14 years here....and I had a 38 year in Industry and a lot of that time was spent overseeing large Maintenance departments....including the electricians and I have designed power systems for 400,000 NEW facilites....and done a LOT of "electronic Process Control"....and was a "Math Failure" during the two years I was in Electrical Engineering....but Graduated with a BS-Engineering and "ACED" to Electrical Engineering courses that the "Smart" guys....ME's CE's MEA's, and even NUCLEAR had to take.. I LEARN EVERY DAY HERE...and enjoy trouble shooting from afar.

We WILL help you and I don't think you have any major issues.....Good Luck.  Do as we ask and report back...Thanks,

 

 

 

[MyronTruex]

If you have a 50 to 30 amp adaptor, or 50 to a normal 110 plug, or some way to get down to a normal three prong plug, connect that to shoreline. Before doing so, turn off any major electric hogs, such as the water heater.

See if your charger comes alive. 

--------------------------------------------------------------------------------------------------------------------------------------------------

A voltmeter on the input of the inverter/charger would be where I go for my first voltage measurement if the above does not cause the charger to come to life.

--------------------------------------

I do not trust that your shoreline is functioning correctly. There are two 110 volt paths that come down the 50 amp connection. Using adaptors makes that voltage come down both lines at the same time.

Your system knows what is coming down those lines and makes changes as needed. 

-------------------------------------------------------------------------------------------

The inverter/charger is a pretty dumb animal. It just needs to be fed 110 volts. If is sees that, it charges, if it does not see that and you have the inverter button on, it drains your batteries. 

----------------------------------------------

You probably have a (30amp), or so breaker in your main breaker panel that feeds the charger. You can take a voltage measurement there with the generator running and on shoreline. Comparing should sort this out in just a few measurements. 

[Tom Cherry]

41 minutes ago, Ray Davis said:

This concerns me since you mentioned a good-ole 20A (non-GFCI).   Where are you getting 240 volts from,  the generator or the 20A receptacle?

solar panel array. We don't have batteries, so they're only active on sunny days. It basically feeds the house and has a 220 RV pick-off. The pick-off says 23A max, and I've seen close to that going to the house, so the system seems to be working well. I won't be running ACs etc--just keeping the batteries up. I measure 122V at each hot leg and 244V hot-to-hot, but I don't have a way to measure the current. The controller was for the previous owner's Tesla charger..we don't own a Tesla. We're waiting to hear from him to see if anything else needs to be done for RV hookup.

YES, Ray, that baffled me also.  Read (yawn) my post.  I don't think he actually "SAID" he had tried it.  I assumed that it was a standard 120 VAC (NON GFCI). 

SO, I focused on that.  I think he has the charging rate set to 100%.  If he has a Res Refer running or even a small load, then the Magnum DOES measure the LOAD...and if it can't "put out" enough current to satisfy the charging requirement...then it says...NOPE...ain't gonna try.  It took a LOT of questions to Magnum to understand that....

SO, he also has an Intellitec (Monaco Proprietary) Board 6 that controls the Big Boy.  When the Magnum puts out current, it does it in proportion to the NEEDS of the batteries...

RAY...YOU ARE A GENIUS.... OK...your comment and my response got me to thinking.

@randys006  You will get an EMAIL on this.  PLEASE READ THE FOLLOWING..... 

I am BASING all my calculations on the way that MY inverter works.  It is a MS2012 or 2000 Watts.  Randy stated...but I did NOT make the connection....RES REFER and S2812.  Technically, it is PROBABLY the MS2812.  IT required a HIGHER input current....as it puts OUT MORE JUICE.  SO, The MS2012....has a MAX Charging rate of 100 Amps.... folks report a smidge more.  The MS2812, once I found the right spec sheet....has a MAX Charging Current of 125 Amps.  

THAT MAY BE or REINFORCES MY THEORY.  He can NOT run or charge at 100%.  When the Magnum "measures" the load (the outlets and microwave standby and res refer....with NO ENERGY SAVER), then it says.... HEY BOSS... You only get 20 Amps of DC power coming in.  I need 125 AMPS....I am trying to TOP OFF the Chassis as well as recharge the HOUSE.  You, in theory....only can give me 154 Amps (DC output).  THAT ain't gonna work..

NOW, throw in Ben's ( @96 EVO comment about a burned out or faulty or high resistance Dog Bone....

That actually ADDS amps (the resistance).  ASSUMING that the Dog Bones are marginally, OK, there is NO way that a 20 AMP circuit can support the higher capacity 2800 Watt Inverter or CHARGER.

SO....the calculations I did were for a 2000 Watt...and you gotta add 25%....

Now, more than before....if he kills the sub panel....or shuts off all the internal power and allows the Magnum Charger to use ALL the 20 amps or whatever....he still needs to "start low" as in a 20% Charging rate.  If it works then....set it higher.  ODDS ARE, if he leaves it on say 30 or 40%, it will, over time, fully charge.  That is my hypothesis.....

Thanks for the comment which sparked that "HEY WAIT A MINUTE" moment.  If you ever watched House MD, then you know the MOMENT....when in his head, House figures out....he MISSED something and then, a random thought....like you brought up, triggered a different look.  2800 Watts just makes it worse....so he needs way MORE than 20 Amps to use at HOME....UNLESS he throttles back the charging rate.

I SURE HOPE THIS IS CORRECT....

Thanks for responding....

[randys006]

2 hours ago, 96 EVO said:

Sounds like you've covered about everything!

I'm assuming you have pressed the 30A-20A button on the Magnum remote panel?

Mine doesn't have a button, but it does have a "Max Shore" setting in the menu. Sounds to me like they do the same thing. Thanks for the suggestion!

[randys006]

Wow, thanks for the great replies everyone! It has a Surge Guard (model 40250-RVC) that acts as the physical side of the transfer switch and offers protection. I think I've been able to track it down to a bad module in there. It has two switches, for the shore and genset, which are magnetically closed. The genset side does close automatically, but the one on the shore side does not. However, the shore side does work when I close the switch manually. (standard disclaimer: it's not recommended that anyone else tries that without HV training and wearing VERY heavy gloves)

I'm guessing it got zapped during the tornado in Michigan, and it worked off and on for a while before finally completely dying. I unplugged the shore power as soon as I noticed the storm, but there were definitely lightening strikes in the area and likely trees dropping before I did. The Surge Guard does mention CAN communication, so it's possible that there is another component that sends it a signal to activate the Shore side, and that's what failed. That's just brainstorming though--I still haven't found any additional documentation that would suggest that other unit exists. It's just as likely that it only uses CAN to send diagnostics to the main brain.

I haven't decided yet if it's worth further testing, to try and find parts, or just replace the whole durn thing...but at least I'm a lot closer!

There were some interesting questions which could help other down the road, so I'll add some more replies later. Thanks again!

[96 EVO]

Well, you sound like you know your way around electricity!

Just take your DVM to the output lugs in the transfer switch with your 20A hooked up!

[randys006]

1 hour ago, Ray Davis said:

This concerns me since you mentioned a good-ole 20A (non-GFCI).   Where are you getting 240 volts from,  the generator or the 20A receptacle?

The 240 comes from the solar panels ON THE HOUSE, not the coach (which are the old bad ones)--which, it's apparent now that I should have been more clear about that haha. The good panels and the pickoff are pretty much directly tied to the utility power (in parallel), and I have since verified it is all working great. Sorry for the confusion... 

[waterskier_1]

I apologize, but dinner is ready, and I only read your original post.  But if your inverter says "inverting" then it is not seeing 110 VAC on its input.  Since you say it works while on generator, but not shore power, it appears that the leg of the 220 that the inverter is on is bad.  That can be anywhere from the power pedestal to the transfer switch.  Easiest to check that you have 220 VAC at the main power panel 50 Amp circuit breaker, and go from there.  I'll try and get to all the other responses after dinner and see where you are sorting this out.

  -Rick N.

[randys006]

59 minutes ago, Tom Cherry said:

solar panel array. We don't have batteries, so they're only active on sunny days. It basically feeds the house and has a 220 RV pick-off. The pick-off says 23A max, and I've seen close to that going to the house, so the system seems to be working well. I won't be running ACs etc--just keeping the batteries up. I measure 122V at each hot leg and 244V hot-to-hot, but I don't have a way to measure the current. The controller was for the previous owner's Tesla charger..we don't own a Tesla. We're waiting to hear from him to see if anything else needs to be done for RV hookup.

YES, Ray, that baffled me also.  Read (yawn) my post.  I don't think he actually "SAID" he had tried it.  I assumed that it was a standard 120 VAC (NON GFCI). 

SO, I focused on that.  I think he has the charging rate set to 100%.  If he has a Res Refer running or even a small load, then the Magnum DOES measure the LOAD...and if it can't "put out" enough current to satisfy the charging requirement...then it says...NOPE...ain't gonna try.  It took a LOT of questions to Magnum to understand that....

SO, he also has an Intellitec (Monaco Proprietary) Board 6 that controls the Big Boy.  When the Magnum puts out current, it does it in proportion to the NEEDS of the batteries...

RAY...YOU ARE A GENIUS.... OK...your comment and my response got me to thinking.

@randys006  You will get an EMAIL on this.  PLEASE READ THE FOLLOWING..... 

I am BASING all my calculations on the way that MY inverter works.  It is a MS2012 or 2000 Watts.  Randy stated...but I did NOT make the connection....RES REFER and S2812.  Technically, it is PROBABLY the MS2812.  IT required a HIGHER input current....as it puts OUT MORE JUICE.  SO, The MS2012....has a MAX Charging rate of 100 Amps.... folks report a smidge more.  The MS2812, once I found the right spec sheet....has a MAX Charging Current of 125 Amps.  

THAT MAY BE or REINFORCES MY THEORY.  He can NOT run or charge at 100%.  When the Magnum "measures" the load (the outlets and microwave standby and res refer....with NO ENERGY SAVER), then it says.... HEY BOSS... You only get 20 Amps of DC power coming in.  I need 125 AMPS....I am trying to TOP OFF the Chassis as well as recharge the HOUSE.  You, in theory....only can give me 154 Amps (DC output).  THAT ain't gonna work..

NOW, throw in Ben's ( @96 EVO comment about a burned out or faulty or high resistance Dog Bone....

That actually ADDS amps (the resistance).  ASSUMING that the Dog Bones are marginally, OK, there is NO way that a 20 AMP circuit can support the higher capacity 2800 Watt Inverter or CHARGER.

SO....the calculations I did were for a 2000 Watt...and you gotta add 25%....

Now, more than before....if he kills the sub panel....or shuts off all the internal power and allows the Magnum Charger to use ALL the 20 amps or whatever....he still needs to "start low" as in a 20% Charging rate.  If it works then....set it higher.  ODDS ARE, if he leaves it on say 30 or 40%, it will, over time, fully charge.  That is my hypothesis.....

Thanks for the comment which sparked that "HEY WAIT A MINUTE" moment.  If you ever watched House MD, then you know the MOMENT....when in his head, House figures out....he MISSED something and then, a random thought....like you brought up, triggered a different look.  2800 Watts just makes it worse....so he needs way MORE than 20 Amps to use at HOME....UNLESS he throttles back the charging rate.

I SURE HOPE THIS IS CORRECT....

Thanks for responding....

Awesome, thanks Tom! Lots of good points to touch on from those posts! I can't say I'll get to them all haha, but since you took the time I'll sure give it a go to show my appreciation...

Troubleshooting skills...well, I'm a nuclear physicist who used to work at linac facilities and a few of the major national labs, so I'm great at diagnosing MW klystrons, measuring million-volt picosecond pulses,  etc., and good fundamentals. I've never really taken the time to "learn" residential or RV systems though, so I consider myself just knowledgeable enough to be dangerous. And of course still learning the terminology...and of course we all always miss things occasionally... :).

On the house solar--I've since learned it isn't a Tesla charger--just a DIY, hardwired 220 receptacle. It's just that they used a panel controller that connects to the Tesla app, so it fooled me.

So, I have found most of the diagrams..just not all of them. In this bad boy, the "250A inline battery fuse" is actually 300A, so it can in theory run the inverter at 100%. That makes me nervous though, especially since I haven't found the stupid fuse yet. I'm hoping to never have to replace it in any case, so I don't run the charger above 90%. Probably overcautious, but...yeah.

To fill in some more info, I have three dogbones--two 50->30 and one 50->20--as well as a 30->20 plug adapter. They all test good on DC resistance, and I tried all possible combinations before posting. However, street sense also tells me to agree that they still shouldn't be trusted 😉 

And you're right on about the 20A power--I'm pretty sure the owner's manual actually says never run on less than 30A shore power. Which of course I interpret as "be very careful not to draw too much when you're running on a 20A circuit." I also do religiously dial back the Shore Max to the source's rating or below, but I don't really trust that, nor the circuit breakers in the source, nor of course the dogbones, so I try to limit low-current hookups to emergency-ish situations. Or in this case, when I'm doing diagnostics.

On battery settings..yep, AGM2. I've had the capacity set to 1000Ah though, sounds like I need to dial that back. Thanks!

On load, again, sorry I didn't supply all the details right off, but I had cut off the 12V and turned off breakers until the Magnum meter read solid 0A. It's interesting, btw, that the minimum the Magnum will display is 11A. I would've thought they came with a better shunt from the factory. The house batteries have a good meter that's sent to the Aladdin. It's not available in "zero load" mode, but that's ok--it's close enough to zero to say the Magnum isn't disabling itself. (at any rate, we now know this almost certainly isn't the case because I found the faulty transfer switch)

Hmm, the paragraph about BIRD and the BIG BOY solenoid is very helpful, but it brings up another question I've had.. The first couple months, I had been seeing significant charge loss on the chassis batteries while boondocking/genny off (presumably running on house battery power only). I had chalked it up to a bad battery (that's why I replaced them), but perhaps something else is failing and causing the battery sets to be permanently connected at some level. I don't have a lot of data with the new batteries yet, but enough to say it isn't critical. If this does continue (or come back), I'll do some more searching then start a new post about it in the future.

Love the humor, btw..my kids were hooked on Dora back in the day and I was riffing on her "swiper, no swipey!" line. Good times, lol.

Ok, that was quite a day. Now it's beer-30. Thanks again all!

[Tom Cherry]

10 hours ago, randys006 said:

Awesome, thanks Tom! Lots of good points to touch on from those posts! I can't say I'll get to them all haha, but since you took the time I'll sure give it a go to show my appreciation...

Troubleshooting skills...well, I'm a nuclear physicist who used to work at linac facilities and a few of the major national labs, so I'm great at diagnosing MW klystrons, measuring million-volt picosecond pulses,  etc., and good fundamentals. I've never really taken the time to "learn" residential or RV systems though, so I consider myself just knowledgeable enough to be dangerous. And of course still learning the terminology...and of course we all always miss things occasionally... :).

On the house solar--I've since learned it isn't a Tesla charger--just a DIY, hardwired 220 receptacle. It's just that they used a panel controller that connects to the Tesla app, so it fooled me.

So, I have found most of the diagrams..just not all of them. In this bad boy, the "250A inline battery fuse" is actually 300A, so it can in theory run the inverter at 100%. That makes me nervous though, especially since I haven't found the stupid fuse yet. I'm hoping to never have to replace it in any case, so I don't run the charger above 90%. Probably overcautious, but...yeah.

To fill in some more info, I have three dogbones--two 50->30 and one 50->20--as well as a 30->20 plug adapter. They all test good on DC resistance, and I tried all possible combinations before posting. However, street sense also tells me to agree that they still shouldn't be trusted 😉 

And you're right on about the 20A power--I'm pretty sure the owner's manual actually says never run on less than 30A shore power. Which of course I interpret as "be very careful not to draw too much when you're running on a 20A circuit." I also do religiously dial back the Shore Max to the source's rating or below, but I don't really trust that, nor the circuit breakers in the source, nor of course the dogbones, so I try to limit low-current hookups to emergency-ish situations. Or in this case, when I'm doing diagnostics.

On battery settings..yep, AGM2. I've had the capacity set to 1000Ah though, sounds like I need to dial that back. Thanks!

On load, again, sorry I didn't supply all the details right off, but I had cut off the 12V and turned off breakers until the Magnum meter read solid 0A. It's interesting, btw, that the minimum the Magnum will display is 11A. I would've thought they came with a better shunt from the factory. The house batteries have a good meter that's sent to the Aladdin. It's not available in "zero load" mode, but that's ok--it's close enough to zero to say the Magnum isn't disabling itself. (at any rate, we now know this almost certainly isn't the case because I found the faulty transfer switch)

Hmm, the paragraph about BIRD and the BIG BOY solenoid is very helpful, but it brings up another question I've had.. The first couple months, I had been seeing significant charge loss on the chassis batteries while boondocking/genny off (presumably running on house battery power only). I had chalked it up to a bad battery (that's why I replaced them), but perhaps something else is failing and causing the battery sets to be permanently connected at some level. I don't have a lot of data with the new batteries yet, but enough to say it isn't critical. If this does continue (or come back), I'll do some more searching then start a new post about it in the future.

Love the humor, btw..my kids were hooked on Dora back in the day and I was riffing on her "swiper, no swipey!" line. Good times, lol.

Ok, that was quite a day. Now it's beer-30. Thanks again all!

OK...thanks for the comments and filling in the blanks.  Problems like this ARE a puzzle....and sometimes the easy ones....get theoretical solutions.  We, the moderating staff have to make sure that some one is "qualified" enough to safely measure live voltages.  Then, the MH's electrical system as to the duplicity as well as the added "Magnum not happy...no AC" quirks...which few under stand.  

Once I get started with my "foundation".... I then veer off the simple path.  Ben and Rick and Myron and others....not slighting them, this morning, made some great observations...  Your background and knowledge fill in the blank helps.  So, my HOPEFULLY simple answer.  NEVER TRUST an ohm meter to tell you what happens when you have a Load, especially a FLA "Full Load Amperage".

Ben's comment about the MOST LIKELY failure....a BAD Dogbone....the cutesy name for the 50-30 or the 30 - 20 makes a lot more sense now.  THEY do fail all the time.  Rick's comment about leg's and Inverting struck a chord.  And Myron's approach.  THEN, I did realize... you DO have voltage and current measuring capabilities.  Your ALADDIN.  I don't know HOW the screens work...but your owner's manual tells you, in inescapable detail....  SO, you have some choices.  Personally, I would fire up the Aladdin....go to the voltage screen....and see.  If you have INCOMING voltage, it will be displayed, Leg by leg....I THINK...as I don't operate that toy.  It also displays the current.  FWIW.  Since you have tech savvy.  The Aladdin gets a MPX data feed from the ATS (Assuming your ATS was never replaced....as LONG as your ATS looks like the one in the manual).  The Aladdin's screen is not from a Toroidal coil....which is the conventional way.  SO, if someone replaced the ATS with a later model or a different kind...that Aladdin feature goes away.  

OK...so if the Aladdin says NO VOLTAGE and presumably NO CURRENT, you have a bad "feed".  The only way to test....should you be so inclined...is to barely pull apart the male from the female and have thin, skinny meter leads and see what is actually occurring.  The easiest....get a now 50 to 30.  The 50 - 30 just combines the HOT, call it L1, from a 30 Amp receptacle....and then the adapter has the LINE (L1) and it is connected to BOTH the L1 and L2 legs....so the 50 Amp THINKS it has both legs...which is does...but it only has, theoretically, 15 Amps for each...a combined total of 30.  OK...bad dogbone....no power.  Same for the 30 to 20....except it just passes the L1 to L1....then the 30 splits.  

If the Aladdin shows NO voltage....then the quickest and easiest test....  Follow Myron's advice.  Pull the main panel cover and check L1 and L2 or RED and BLACK to the White Neutral Bar or Ground.  NO VOLTAGE....then no incoming power. NOW....the other option, if it is readily accessible...pull off the cover of the ATS.  There is a LINE set of terminals.  NO LINE (SHORE) no juice.  Do your measurement there.  

MY ORIGINAL comments, long as they were....IF the Genny is working....and you can charge....then you do NOT HAVE a Magnum failure.  The Magnum does NOT know the ONAN's juice compared to the Power Company's JUICE....240/120 60 Hz is the same.  NOW, if you DID have a failure in the ATS, then, you would NOT have outgoing voltage.  We KNOW you have outgoing voltage, making the Inverter Charge from the Genny.

If you pull the cover off the ATS...and check the LINE or SHORE and have voltage...then checking the MAIN (or OUTPUT) would tell you is the ATS works.  Resistance checking is great....but with higher currents, it is often a "hidden" termination....like inside a molded connector.  We have had MANY failures of a 4 prong Shore power plug...folks have ASSUMED the worst and replaced the whole line set....when just cutting off the bad male end and putting a new one one works.  AGAIN...experience and KISS>

OK...one final trick....Leave the hookups the same.  BUT, gently PULL apart your 50 Amp shore from the adapter.   Maybe extend it 3/16".  I often check a pedestal, under load by doing that.  My meter leads will then slip in and I can measure voltage.  You should have 120 VAC from the two side terminals (L1 and L2) to the round (ground) of the opposite end (flat) Neutral.  If you don't have that....the game is over...one of the adapters is DEAD....

Good Luck....keep us posted...

 

[MyronTruex]

"""To fill in some more info, I have three dogbones--two 50->30 and one 50->20--as well as a 30->20 plug adapter. They all test good on DC resistance, and I tried all possible combinations before posting. However, street sense also tells me to agree that they still shouldn't be trusted """"

 

DC resistance testing is just about useless. Any ohmeter will and can fool you. One wire from a stranded pair will carry enough current and voltage to make the meter read zero ohms.

From one Klysitron changer to the other, get your voltmeter onto the input of the charger. This should eliminate all of the systems inline with it. This will eliminate weak shoreline voltage/current. IR drop from a heavy load that is. 

You charger is inverting because it does not see the proper shoreline voltage, or it is broken. 

Heck, you could pull the inverter/charger out and set it on a workbench with a cheater cord and check it. I am NOT suggesting that. I just want to make the point that you may be shooting in the dark without real measurements. 

You would never change a klystron without measuring the B+. 

If it satisfies your need. Start the generator and go into the Magnum setup and turn the charger down to 10 or 20 percent if yours has that feature. I do this when on light weight shorelines. 30 amp or less for example. Once the batteries are full, 10% will keep them up just fine. 

Edited October 27, 2023 by myrontruex

[Steven P]

Yall are way above my head w this post, but I have a question. In the original post, it states 4 12V AGM house batteries.  Is that correct or should it be 4 6V?  Would that make a difference in this situation?  The PO of my coach had 2 12V batteries and when 1 went bad, I had numerous issues until I replaced the batteries (w 4 6V AGM).  However, my Magnum charger still showed charging on the remote panel even w the bad batteries.  I don't think this is relevant since it will charge on genny power, but asking for a friend. 😀

[MyronTruex]

Good eyes Steven,

I suspect most of us assumed he meant 6 volters. There would likely be some smoke involved with four 12 volters . In addition, he stated things worked on generator as well as on a 50 amp shoreline. 

Not 100% clear on your batteries. Your previous owner had two 12 volt batteries in place of where four 6 volters previously lived?

That is possible. Living on shoreline a person really does not need a load of heavy batteries to get by with. 

In any case, your charger would likely continue to charge, even with bad batteries. It will do its best to fill up the empty electron bucket, however the bad battery will never come up to the proper voltage and the charger will keep trying to get it up to a charged state. 

 

[Tom Cherry]

1 hour ago, Steven P said:

Yall are way above my head w this post, but I have a question. In the original post, it states 4 12V AGM house batteries.  Is that correct or should it be 4 6V?  Would that make a difference in this situation?  The PO of my coach had 2 12V batteries and when 1 went bad, I had numerous issues until I replaced the batteries (w 4 6V AGM).  However, my Magnum charger still showed charging on the remote panel even w the bad batteries.  I don't think this is relevant since it will charge on genny power, but asking for a friend. 😀

@randys006

GOOD catch by Steve.  If you do have 4 of the 12 VDC AGM Deep cycles, then you need to look at the batteries or google.  The AGM's are only rated at 100 AH.  Guess it is one of them AGM Thingies.  SO, following the rules....4 in Series, assuming 100 Amp Hours would be 400....so set the AH there.  Never realized the AGM's were rated at half the AH of a Flooded Cell.

Guess we all learn.  BUT, in reality....to ME, it don't change things.  The MAX Current out of the MS2812 is 125 A DC....so with a 20 amp supply.....scary CLOSE.

BUT, if the Charger is not ON....then, will go back to "CHECK the power, at each connection, with a LOAD" or see what your Aladdin says.

[waterskier_1]

2 hours ago, myrontruex said:

Good eyes Steven,

I suspect most of us assumed he meant 6 volters. There would likely be some smoke involved with four 12 volters . In addition, he stated things worked on generator as well as on a 50 amp shoreline. 

Not 100% clear on your batteries. Your previous owner had two 12 volt batteries in place of where four 6 volters previously lived?

That is possible. Living on shoreline a person really does not need a load of heavy batteries to get by with. 

In any case, your charger would likely continue to charge, even with bad batteries. It will do its best to fill up the empty electron bucket, however the bad battery will never come up to the proper voltage and the charger will keep trying to get it up to a charged state. 

 

There would be no smoke or other ill effects if the four 12 volt batteries were connected in parallel.  

1 hour ago, Tom Cherry said:

@randys006

GOOD catch by Steve.  If you do have 4 of the 12 VDC AGM Deep cycles, then you need to look at the batteries or google.  The AGM's are only rated at 100 AH.  Guess it is one of them AGM Thingies.  SO, following the rules....4 in Series, assuming 100 Amp Hours would be 400....so set the AH there.  Never realized the AGM's were rated at half the AH of a Flooded Cell.

Guess we all learn.  BUT, in reality....to ME, it don't change things.  The MAX Current out of the MS2812 is 125 A DC....so with a 20 amp supply.....scary CLOSE.

BUT, if the Charger is not ON....then, will go back to "CHECK the power, at each connection, with a LOAD" or see what your Aladdin says.

Nooooo.  If connected four 100 A-Hr AGM (or any other chemistry batteries) in SERIES, you would still end up with 100 A-Hrs, but it would be 48 VOLTS!!  Now you really would see the smoke Myron mentioned in his post.  Clearly, the batteries are NOT connected in Series.

Now, if you connected the four 100 A-Hr batteries in PARALLEL, you would still have the 12 Volts, but since each battery is contributing 100 A-Hrs to the total "system", you would have 400 A-Hrs.

I have seen this done, but it is rare.  In fact, back in college, we were taught that it was a poor design to install batteries in parallel, since the internal resistance of each battery varies (maybe more 50 years ago) and one battery would discharge to the level of the poorest battery.  Series does not have this problem.  Of course, that assumed we could spec a battery with the required current and voltage requirements need for the design, and didn't have to "make do" with what was available "off the shelf" meaning not custom designed.

In any case, as long as the batteries were connected in any combination that yields 12 volts, no smoke.  Regarding the Maximum output of a battery charger (Magnum or otherwise) that is the Maximum Current that the Battery Charger can deliver.  The batteries can't suck or draw more current (combined with other DC loads) that that maximum.  So, if I have 50,000 A-Hr batteries that need charging, it will not hurt the charger, it just may take over a year, assuming no further discharge.  Nothing is hurt or damaged.  Now, that is not true if we are speaking voltage.  It must be the proper voltage for the system.  If readers think it necessary for more details of Circuits 101, I think it best to start another post.

  -Rick N.

[Steven P]

3 hours ago, myrontruex said:

Good eyes Steven,

Not 100% clear on your batteries. Your previous owner had two 12 volt batteries in place of where four 6 volters previously lived?

That is possible. Living on shoreline a person really does not need a load of heavy batteries to get by with. 

Yes, he had 2 12V flooded batteries wired properly (parallel?) for 12V output.  I never got to talk to him as he had passed away before we bought the coach.  But it seems they used the genny a lot and likely rarely boondocked.  I went back to 4 6V AGM when I changed. 

[randys006]

Oops, guess I never hit 'send' yesterday. Guess y'all are getting two for the price of one.

------------------------------------------------------------------------------------------
Update from yesterday (10/27): popped the board out of the ATS and did some bench testing, poked around, and verified that either or both of the shore power control and relay are toast. I wasn't really able to test the relay since I don't have a schematic, but the few things I tried would not get it to engage. (details omitted for safety purposes/CYA)

I learned that the company (formerly TRC, mine is a Surge Guard 40250 btw) is now part of Southwire and they do still sell a comparable unit...the 40450RVC3, for a paltry $1200... I found a cheaper version (40100) at the local camping world for $189. They actually still use the exact same switches that mine has! Although, the physical contacts on the original unit are fine--I do get full power when I hold the switch closed manually. I'm seriously considering going Mythbusters on the thing and attaching a linear actuator on it so I can engage it manually when I need to...I'll let y'all know what I decided in a few days 😉 
------------------------------------------------------------------------------------------
Today (10/28): I decided to use the new 40100 and and since the RV-C diagnostics from the 40250 were still working, I'm hoping to reuse it's board. The sensors are usually passive, and with digital communication I expect it to work.I'm pleased that say that it was a success and everything is working great! The Aladdin displays all the diagnostics without complaint. I also picked up an external surge protector since the 40100 doesn't have one.

On the 40250 RV-C board, it seemed important to connect it the same as the original, so I labeled everything clearly before starting. The 40250 (old one) has three sets of 3-wire voltage probes; red-white-green for both inputs (shore and genset) and output which are color-matched to standard 240V RV wiring. The 40100 (new one) already had extra spade terminals on all of the inputs, and I scavenged some of the spade terminals from the 40250 for the output side. This allowed me to reuse all of the existing wires from the 40250. Let me mention that it's important to make sure you're not overloading anything when adding circuitry like this. In this case, the probe terminals are directly connected to the inputs and the size of the wires (in the 24-28 gauge range) tells us that it is low power. Since it's the same manufacturer and I can see a lot of the hardware on the board, I'm quite confident it's a "dumb" measurement and the boards will not interfere with each other. For current probes, the 40250 simply had two transformers (the donut type), one on each HOT output leg. The 40250 (old one) had an extra screw block where the wires from the relay output connect on one side, and the feed to the main circuit breaker on the other. The 40100 (new one) did not have that block, so I just slipped one transformer onto each of the red and black feed wires before connecting them to the output.

It's still a mess right now, and I need to go pick up an enclosure for the 40250 board (it's existing box is WAY too big to reuse). I'll post some pics after I finish getting it all buttoned up and tidy in a couple days.

Cheers 🙂

[randys006]

13 hours ago, Steven P said:

Yall are way above my head w this post, but I have a question. In the original post, it states 4 12V AGM house batteries.  Is that correct or should it be 4 6V?  Would that make a difference in this situation?  The PO of my coach had 2 12V batteries and when 1 went bad, I had numerous issues until I replaced the batteries (w 4 6V AGM).  However, my Magnum charger still showed charging on the remote panel even w the bad batteries.  I don't think this is relevant since it will charge on genny power, but asking for a friend. 😀

Your question piqued my curiosity, so I scrubbed off the road grime and checked. Mine are 4 x LIFELINE GPL-4DL, 12V, 210Ah, all in parallel. Yeah, that would suck if one went bad because it'll pull down all the other 3 and reduce their lifespans too.

[Just Jim]

Randy,  In a word... you have skills.  I had an idea it was transfer switch related, but I'm a plug and play kind of guy.  Congrats on getting it sorted out.