Jump to content

Load Shedding


tmw188

Recommended Posts

Todd,

I suspect that your EMS board is the older version 684 with the 3 amp fuse and has most likely failed SO that's why it has been basically disconnected. Wires have been removed from the relays and tied together with wire nuts.

If you want to restore the EMS function to your coach, you will now need to purchase an Upgrade EMS Kit that includes a new upgraded EMS Control board (#894) with a current sensor, a new Display and two new electrical pigtails. Then follow the installation instructions as to how to set it up for the shedding order that you prefer.

There are vendors on the Internet that offer these kits. It should be under $500 for everything.

 

Edited by Dr4Film
Link to comment
Share on other sites

29 minutes ago, Dr4Film said:

Todd,

I suspect that your EMS board is the older version 684 with the 3 amp fuse and has most likely failed SO that's why it has been basically disconnected. Wires have been removed from the relays and tied together with wire nuts.

If you want to restore the EMS function to your coach, you will now need to purchase an Upgrade EMS Kit that includes a new upgraded EMS Control board (#894) with a current sensor, a new Display and two new electrical pigtails. Then follow the installation instructions as to how to set it up for the shedding order that you prefer.

There are vendors on the Internet that offer these kits. It should be under $500 for everything.

 

Thanks for the info, I’ll record the info you posted in my service manual. I think it’s going to stay the way it is for now. Front shocks are way more important on my list. 

Link to comment
Share on other sites

2 hours ago, W7BE_Bob said:

X2 Your board is bypassed. Check the other picture and you'll see a CB wire to one terminal for the relay and the romex hot wire to the other for each device that's shedded.

Here is a full picture of my panel opened up. I did trace down the above bypassed circuits against the panel cover labels just for curiosity.  Before someone ask the panel is Not hot. 

9092C119-E651-40B1-A3FF-59E41FED0D59.jpeg

Edited by tmw188
Link to comment
Share on other sites

Todd,

Those four sets of wires that have been tired together with wire nuts are most likely for the front AC, the rear AC, the water heater and the washer/dryer.

The wires would normally have gone over to the appropriate relay on the control board in the order that they would be shed when on 30 amps or less shore power.

You will note that each wire coming from the CB is a different color whereas the wire that it is attached to is always black which is the load wire for the device.

Edited by Dr4Film
Link to comment
Share on other sites

Quote

From your picture it looks like the EMS board has already been bypassed.  If all the circuits work with 50 amp and 30 amp then you will have to monitor what you are using and control the total load manually.

I agree the EMS has been bypassed by someone.  The 120 volt wires should be attached to the terminals.  The board may have failed for the previous owner and was just bypassed.  The manual should show you the proper connections and then you test the board.  Many had the relays on the board fail.

Link to comment
Share on other sites

35 minutes ago, Bob Blackmon said:

The wires on the 2 pole 50 have been seriously hot. When removed from power you may want to see if the connections are tight.

Bob hey thanks for the observation! I checked all the wire terminals going into all the breakers and all were tight. I believe it looks concerning in the photo more than in person, but I will look at them again. That Neutral looks a little like those hots if you look closely following the wire. Insulation looks twisted?  I’ve seen that before on heavy stranded wire. Good observation I will certainly look at them again. 

20 hours ago, Dr4Film said:

Todd,

Those four sets of wires that have been tired together with wire nuts are most likely for the front AC, the rear AC, the water heater and the washer/dryer.

The wires would normally have gone over to the appropriate relay on the control board in the order that they would be shed when on 30 amps or less shore power.

You will note that each wire coming from the CB is a different color whereas the wire that it is attached to is always black which is the load wire for the device.

Could be, my labeling for the breakers are probably the same as yours. I’ll try to diagnose what parts or board has failed. I think there are two boards there if I remember correctly. One might be just the terminal block but I think there were some circuitry on that board too.

Edited by tmw188
Link to comment
Share on other sites

1 minute ago, itdave47 said:

I don't which board I have but mine failed a few years ago and I was able to repair it. The relays are common and avaliable thru Amazon. If you are good with soldering on a PCB you can replace the failed relays.

I have the tools for soldering CB’s and a little bulb vacuum that removes the old solder. If you could post the relay PN’s you used I’ll probably do that. That would be less money than complete boards. I’ll need to determine with certainty which relays are bad, but probably pretty typical failure. 

Link to comment
Share on other sites

There could be one other possibility on why the board was bypassed by a previous owner.  I am NOT suggesting it was a good idea in the first place, but IF they often used one of those 50A cheater dog bones to plug into a 30A and a non GFI 20A pedestal to "get more amps", AND both the pedestal breakers were on the same leg of the split phase, then the coach EMS would still think it was only a 30A input (as 240V would not have been detected) and load shed things the previous owner was trying to avoid by the extra current from the extra 20A pedestal breaker.  I.e. they were trying to run 2 A/C's in a 30A site that had a non GFI 20A pedestal breaker also in the box ... so they just bypassed the EMS.  In this hypothetical case, the board & display could still be possibly good.  So you might want to fully test the board before just assuming it is bad.  Just saying as it could be an off chance possibility not knowing for sure why it was previously bypassed. 

And we all know such a practice could overload the neutral wire as all current would be returning via the neutral whereas in a full phase 240V circuit only the difference is on the neutral.

Link to comment
Share on other sites

8 minutes ago, tmw188 said:

I have the tools for soldering CB’s and a little bulb vacuum that removes the old solder. If you could post the relay PN’s you used I’ll probably do that. That would be less money than complete boards. I’ll need to determine with certainty which relays are bad, but probably pretty typical failure. 

It has been a number of years so don't remember the PN. However if you pull the board you should be able to read the part numbers on the relays. I just checked to manual and although it has a lot of info there are no part numbers. I checked my Amazon order and did not find the relay so now I am unsure where I got them.

Link to comment
Share on other sites

It there a simplier way to disable a working load shedding system than bypassing all of the circuits?

Unbelievable but a CG I'm going to has 2x 30A plugs and they suggest using the cheater cord. They had no idea if the 2 hots on the 30A plugs are 240V or not so I won't know if the load shedding has to be disabled before I get there and test the pedestal. 

I'm not concerned with overloading the 50A wiring neutral with 60A even if I should draw 60A which is unlikely. Overloading one of the 30A neutrals in the cheater cord is possible of course and I'll take that risk. Overloading the 30A neutral in the 30A pedestal is not my concern since the CG recommends using the adapter. I'm also aware of the possible safety issue on not having a dual CB on the 2 hots. 

 

 

Link to comment
Share on other sites

1 hour ago, itdave47 said:

It has been a number of years so don't remember the PN. However if you pull the board you should be able to read the part numbers on the relays. I just checked to manual and although it has a lot of info there are no part numbers. I checked my Amazon order and did not find the relay so now I am unsure where I got them.

Ok well I appreciate the effort looking. I will look into it. Busy installing new LED lights and faucets, and cabinet hdwr but I’ll get to it. 

1 hour ago, W7BE_Bob said:

It there a simplier way to disable a working load shedding system than bypassing all of the circuits?

Unbelievable but a CG I'm going to has 2x 30A plugs and they suggest using the cheater cord. They had no idea if the 2 hots on the 30A plugs are 240V or not so I won't know if the load shedding has to be disabled before I get there and test the pedestal. 

I'm not concerned with overloading the 50A wiring neutral with 60A even if I should draw 60A which is unlikely. Overloading one of the 30A neutrals in the cheater cord is possible of course and I'll take that risk. Overloading the 30A neutral in the 30A pedestal is not my concern since the CG recommends using the adapter. I'm also aware of the possible safety issue on not having a dual CB on the 2 hots. 

 

 

I have one of these for that situation. 

02AB3D48-1961-4818-BC3A-4E650FC40A90.jpeg

1 hour ago, amphi_sc said:

There could be one other possibility on why the board was bypassed by a previous owner.  I am NOT suggesting it was a good idea in the first place, but IF they often used one of those 50A cheater dog bones to plug into a 30A and a non GFI 20A pedestal to "get more amps", AND both the pedestal breakers were on the same leg of the split phase, then the coach EMS would still think it was only a 30A input (as 240V would not have been detected) and load shed things the previous owner was trying to avoid by the extra current from the extra 20A pedestal breaker.  I.e. they were trying to run 2 A/C's in a 30A site that had a non GFI 20A pedestal breaker also in the box ... so they just bypassed the EMS.  In this hypothetical case, the board & display could still be possibly good.  So you might want to fully test the board before just assuming it is bad.  Just saying as it could be an off chance possibility not knowing for sure why it was previously bypassed. 

And we all know such a practice could overload the neutral wire as all current would be returning via the neutral whereas in a full phase 240V circuit only the difference is on the neutral.

Good thought, I will be checking into that. Thank you.

Link to comment
Share on other sites

5 hours ago, itdave47 said:

I don't which board I have but mine failed a few years ago and I was able to repair it. The relays are common and avaliable thru Amazon. If you are good with soldering on a PCB you can replace the failed relays.

Here is the board with the relays. I can hook them backup I suppose and plug the connectors back in on the back. Until I look to verify but I assume each one plugs into its own relay 1,2,3,and 4, in whatever order the std setup is. Maybe I can find the relays online and solder them in?

03564E16-5507-4750-9459-14BD663E5A26.jpeg

2E4C368C-ECE5-4077-B889-E3F2C3CF4DBA.jpeg

Edited by tmw188
Additional info
Link to comment
Share on other sites

I can't read the #'s on Todd's relays, but they could be these??? https://www.google.com/search?q=g8p-1a4p

These single pole normally open relays seem to be popular in my coach in a lot of places on various Intellitec boards.  To fix a random engine shut down issue, back in 2018 I paid (overpaid) 11.38 for 2 of them because shipping was more than the parts, but I could only find them online.  I have no clue if your board uses a normally open or nomally closed design.

Link to comment
Share on other sites

50 minutes ago, Dr4Film said:

Todd, do you have the manual for this older version control board?

If not I can post one.

I have this manual. There is info in there that might say. I would have study this some but it seems they could be either depending what pin they are on maybe? Right now over my pay grade. 

26B1B872-5324-4FA2-985B-E4CC05EAAB6A.jpeg

9B505A34-5725-4E27-B6DB-37F80F3133FA.jpeg

BE5FA88E-B439-40E4-B207-9E6AC8FC5C91.jpeg

1EC56D02-58A4-49D2-858F-E8E796EC7644.jpeg

Edited by tmw188
Link to comment
Share on other sites

16 hours ago, amphi_sc said:

I can't read the #'s on Todd's relays, but they could be these??? https://www.google.com/search?q=g8p-1a4p

These single pole normally open relays seem to be popular in my coach in a lot of places on various Intellitec boards.  To fix a random engine shut down issue, back in 2018 I paid (overpaid) 11.38 for 2 of them because shipping was more than the parts, but I could only find them online.  I have no clue if your board uses a normally open or normally closed design.

The EMS board uses NC relays such that once the amp draw gets to a certain level the appropriate relay will OPEN shutting down that device reducing the amp draw of the coach.

Link to comment
Share on other sites

If I could find the relays I might try one. If they are NC I should be able to test them pretty easy if I pulled the board off. Being it’s bypassed and nothing is plugged in I should be able to remove it seems? 

Link to comment
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
×
×
  • Create New...