No AC power in coach - Inverter Panel Showing "Waiting for AC"

[privcap1]

Hello everyone,

I just sold our beloved Windsor to a nice couple.  They took it home a few days ago.  This is their first motorhome.  I said I would help them out for awhile if they have questions or problems.  I'm currently stumped on a problem that they have encountered.

Problem:

No AC power on shore nor on generator.  The inverter panel says "Waiting for AC" when on shore or on generator.  They said they have not had shore and generator on at the same time.

Background:  

The new owner had unwittingly been using 30 amp shore power with an "open ground" (according to the surge protector).  He turned on the washer/dryer which started to smoke and flipped it's breaker.   

Since then no AC power to the coach. 

Trouble shooting:

There is power going in and coming out of all AC breakers including L-1 and L-2 panel breakers.

The inverter "appears" to be working and the breaker is not flipped.

New owner states all breakers are on.

Could the transfer switch be faulty?

Is the transfer switch up or down stream of the breaker panels?

Any other possible causes?

Edited April 11, 2021 by privcap1
deleted word

[waterskier_1]

First, you state "There is power going in and coming out of all AC breakers including L-1 and L-2 panel breakers."  If this is true, then there is power, coming from somewhere, through the transfer switch to the main breaker panel.  Can they check to see if it is going through the main breaker circuit breakers?  Then is it going through any of the individual circuit breakers?  Specifically, in the main breaker panel, there is an Inverter circuit breaker, usually 30 Amps (sometimes there are two, one for each leg, L-1 & L-2.  Is there power coming out of those?

Next you state "The inverter "appears" to be working and the breaker is not flipped."  Does this mean that when there is no applied power (shore or genny) that the inverter is producing 110 VAC?  If so, then the inverter indeed appears to be working.  That said, the error message is indicating that the inverter charger does not see any AC on it's input.  Is the charger turned on (typically a remote panel push on/push off switch)?  

After responses to these questions, I'll try to further narrow down the problem.  My gut feeling is that when the washer smoked, it may have taken out part of the inverter/charge box, namely some of the charger and associated bypass circuitry.  Many don't realize that all AC power circuits that run off the inverter when no shore/genny power is available, run through the inverter.  That is so the inverter can sense if there is incoming AC (in which case it simply passes it through and out the output AC terminals of the inverter.  When it senses no incoming AC power, it turns off the battery charger, turns on the inverter and its internal transfer switch switches the output of the inverter to the inverted AC.  It sounds like the inverter is not sensing incoming AC.  

[Rick A]

31 minutes ago, privcap1 said:

Hello everyone,

I just sold our beloved Windsor to a nice couple.  They took it home a few days ago.  This is their first motorhome.  I said I would help them out for awhile if they have questions or problems.  I'm currently stumped on a problem that they have encountered.

Problem:

No AC power on shore nor on generator.  The inverter panel says "Waiting for AC" when on shore or on generator.  They said they have not had shore and generator on at the same time.

Background:  

The new owner had unwittingly been using 30 amp shore power with an "open ground" (according to the surge protector).  He turned on the washer/dryer which started to smoke and flipped it's breaker.   

Since then no AC power to the coach. 

Trouble shooting:

There is power going in and coming out of all AC breakers including L-1 and L-2 panel breakers.

The inverter "appears" to be working and the breaker is not flipped.

New owner states all breakers are on.

Could the transfer switch be faulty?

Is the transfer switch up or down stream of the breaker panels?

Any other possible causes?

Symptom indicate a Blown transfer switch. One of the poles on the shore power post would likely have caused this. 
The transfer switch simple switches the power from the generator to shore power when it is detected. 
Transfer switch typically located very close to the shore power in box. 
Mine cost me about $90??

 

4 minutes ago, waterskier_1 said:

First, you state "There is power going in and coming out of all AC breakers including L-1 and L-2 panel breakers."  If this is true, then there is power, coming from somewhere, through the transfer switch to the main breaker panel.  Can they check to see if it is going through the main breaker circuit breakers?  Then is it going through any of the individual circuit breakers?  Specifically, in the main breaker panel, there is an Inverter circuit breaker, usually 30 Amps (sometimes there are two, one for each leg, L-1 & L-2.  Is there power coming out of those?

Next you state "The inverter "appears" to be working and the breaker is not flipped."  Does this mean that when there is no applied power (shore or genny) that the inverter is producing 110 VAC?  If so, then the inverter indeed appears to be working.  That said, the error message is indicating that the inverter charger does not see any AC on it's input.  Is the charger turned on (typically a remote panel push on/push off switch)?  

After responses to these questions, I'll try to further narrow down the problem.  My gut feeling is that when the washer smoked, it may have taken out part of the inverter/charge box, namely some of the charger and associated bypass circuitry.  Many don't realize that all AC power circuits that run off the inverter when no shore/genny power is available, run through the inverter.  That is so the inverter can sense if there is incoming AC (in which case it simply passes it through and out the output AC terminals of the inverter.  When it senses no incoming AC power, it turns off the battery charger, turns on the inverter and its internal transfer switch switches the output of the inverter to the inverted AC.  It sounds like the inverter is not sensing incoming AC.  

Good diagnostic analysis. 

[waterskier_1]

If it were a transfer switch, he would not have power at the main breaker panel, L-1 & L-2.

 

[Dwight Lindsey]

I agree with Rick.  If there is power at the main breaker in the coach, then the problem is not the transfer switch.  What inverter is in the coach?  Magnum?  There are push button breakers on the Magnum that the new owners may not know about.

[Rick A]

4 minutes ago, waterskier_1 said:

If it were a transfer switch, he would not have power at the main breaker panel, L-1 & L-2.

 

Is it possible that only one phase is blown in the switch? That would result in power in one phase of the system and not the other? A volt meter is the next tool of choice. 

[Dwight Lindsey]

In our coach there are two and only two 120v outlets that don't go through the inverter.  They are on the right and left side of the bed.   I don't know about the Windsor . . . if the Windsor also has some 120v outlets that don't go through the inverter, it would be interesting to see if there is power on those outlets.

[waterskier_1]

2 minutes ago, Rick A said:

Is it possible that only one phase is blown in the switch? That would result in power in one phase of the system and not the other? A volt meter is the next tool of choice. 

Not if he is reading AC power at both L-1 and L-2 at the main power panel.

 

 

[Dwight Lindsey]

One other thing to check is any GFI outlet(s).  In our coach the GFI in the bathroom protects all or at least most of the outlets in the front of the coach, including the front TV.  If the GFI is tripped, there won't be power in some or all of those outlets.  Again, I don't have a Windsor . . .

Edited April 11, 2021 by Dwight Lindsey

[privcap1]

Hello all,

After reading your posts I got to thinking that when he did his voltage checks at the breaker panels that maybe he was unknowingly running on inverter power.  I've sent him a text to confirm it. 

So if he has inverted AC power but no power on shore or generator then would that indicate a bad transfer switch?

Edited April 11, 2021 by privcap1

[Chuck B 2004 Windsor]

Did the new owner plug his coach into a 120 vac 30 amp receptible that are used in a campground, or 220 vac 30 amp receptacle used in a home environment?  If he plugged into a 220vac one, he is in for some very expensive repairs.  I have been a member of this group since its beginning.  There are over a dozen members who made that mistake.  Chuck B 

[waterskier_1]

9 minutes ago, privcap1 said:

Hello all,

After reading your posts I got to thinking that when he did his voltage checks at the breaker panels that maybe he was running on inverter power.  I've sent him a text to confirm it. 

So if he has inverted AC power but no power on shore or generator then would that indicate a bad transfer switch?

What year of Windsor?  The older ones (90s) were wired differently than newer one.  In any case, there should be no way that inverted AC should ever get back to the main breaker panel.  That is why the AC from the Main Breaker panel runs through the inverter and then out to the outlets, but never should it get back to the main power panel.

 

[Guest Ray Davis]

 

1 hour ago, privcap1 said:

The new owner had unwittingly been using 30 amp shore power with an "open ground" (according to the surge protector).  He turned on the washer/dryer which started to smoke and flipped it's breaker.   

Before the new owner proceeds someone should determine for sure what that 30 amp shore power is.

If he is using an old style dryer receptacle it's possible that 240v without a neutral went into the coach.  People have used those 3 wire dryer receptacles by making the ground wire a substitute neutral although it would undersized.  In this case when you say open ground and 30 amps, open neutral is what I think of.

[privcap1]

Ray,  the washer/dryer that smoked and flipped the breaker was the splendide unit in the coach.  According to him the 30 amp shore power he was using had "an open ground" light on the surge protector.  I'm pretty sure that washer/dryer is 120 volt AC.

Edited April 11, 2021 by privcap1

[Rick A]

15 minutes ago, Ray Davis said:

 

Before the new owner proceeds someone should determine for sure what that 30 amp shore power is.

If he is using an old style dryer receptacle it's possible that 240v without a neutral went into the coach.  People have used those 3 wire dryer receptacles by making the ground wire a substitute neutral although it would undersized.  In this case when you say open ground and 30 amps, open neutral is what I think of.

Is it possible that the shore power supply has tripped something in the park system? 

[Guest Ray Davis]

In the original post it shows that it is an 03 Windsor.

The new owner just took possession so the coach is probably at their home.  That's where people can rig up electrical hook ups and get into trouble.

Yes the coach washer dryer is 120v,  the one in a house is 240v,   actually all of the appliances in an 03 Windsor are 120v

Chuck is right,  things can be damaged especially electronics when they are subjected to 240v

[privcap1]

55 minutes ago, Chuck B said:

Did the new owner plug his coach into a 120 vac 30 amp receptible that are used in a campground, or 220 vac 30 amp receptacle used in a home environment?  If he plugged into a 220vac one, he is in for some very expensive repairs.  I have been a member of this group since its beginning.  There are over a dozen members who made that mistake.  Chuck B 

Chuck that's a good question. He was plugged into 30 amp supply in a large heated shop on his farm.  I hope it's not a 220 outlet.  I'll relay that to him. 

What all could he have damaged if on 220?

Edited April 11, 2021 by privcap1

[Harvey Babb]

I think Ray is on the right track, and if they did indeed have 230 coming in damage to the transfer switch (as well as a host of other devices) would be likely. Damage to the control board in the transfer switch and/or its relays could prevent power from either shore or generator from getting through.

The transfer switch selects (generator OR shore) (with shore being dominant) and feeds the main breaker. Power from the main feeds branch breakers, and one of the branch breakers feeds the inverter/charger.

In the inverter, (branch power OR inverter power) feeds (through breakers in the inverter) one or more branch circuits that go to some outlets and certain appliances. 

Make sure that the new owner understands the difference between "ground" and "neutral" as too many people confuse the two.

 

[waterskier_1]

10 minutes ago, Harvey Babb said:

I think Ray is on the right track, and if they did indeed have 230 coming in damage to the transfer switch (as well as a host of other devices) would be likely. Damage to the control board in the transfer switch and/or its relays could prevent power from either shore or generator from getting through.

The transfer switch selects (generator OR shore) (with shore being dominant) and feeds the main breaker. Power from the main feeds branch breakers, and one of the branch breakers feeds the inverter/charger.

In the inverter, (branch power OR inverter power) feeds (through breakers in the inverter) one or more branch circuits that go to some outlets and certain appliances. 

Make sure that the new owner understands the difference between "ground" and "neutral" as too many people confuse the two.

 

This is NOT True.  All our coaches use 50 Amps at 220 (or 230) VAC.  Simply plugging into a 230 VAC, 30 Amp outlet would not necessarily cause any problems.  Granted, there might not (depending on the 230 VAC, 30 Amp outlet used) have a separate ground and neutral.  What really matters is how he connected (adapted) the Dryer Outlet to his coach power plug.  

 

[Dwight Lindsey]

There seems to be power on the main breaker in the coach.  So my guess is that the transfer switch is OK.  What I'd do is plug the coach into a known good 110v outlet in the barn to make very sure you're not on 220v, then make sure the inverter circuit breakers are not tripped and the GFI is not tripped, then see where you are

Dwight

[privcap1]

The new owner just confirmed he was plugged into residential 220 when the washer/dryer smoked and he lost AC power to the coach. Not good!

I guess that would explain everything.  He says now there there is only partial power at the 120 and 240 panel when on inverter or generator.

What should he do now? Have an electrician go through the whole thing and see what's fried.  I'm assuming most 120 appliances can be shot hey?  Including the inverter and transfer switch?

[waterskier_1]

3 minutes ago, privcap1 said:

The new owner just confirmed he was plugged into residential 220 when the washer/dryer smoked and he lost AC power to the coach. Not good!

I guess that would explain everything.  He says now there there is only partial power at the 120 and 240 panel when on inverter or generator.

What should he do now? Have an electrician go through the whole thing and see what's fried.  I'm assuming most 120 appliances can be shot hey?  Including the inverter and transfer switch?

See if you can get the details of how he connected the coach to the 220 Dryer outlet.  As I said above, all our coaches use 220 Volts when we are connected to 50 Amp service.  I realize that many are uninformed on this.  Depending on how he connected the coach, it might not be a major problem.  I'm assuming that it didn't have a Power Surge Protection device.  The problem he might have is the open neutral, if he didn't connect it.  I'm not sure why he wouldn't have generator power though.  Do you know if the washer/dryer is connected to run on the inverter or only shore/generator power.   This may seem like a dumb question, but I just found that my washer/dryer is indeed on the inverter - but I have a 3000 Watt inverter so maybe that's the difference.  

 

[privcap1]

I'll have to get more info from him.  I wondered too how he plugged into 220 outlet in his shop with the 50 amp surge protector or the 30 amp adapter plug. The outlet in his shop is probably for a clothes dryer or a welder.

I'm thinking he's not a happy guy right now.

[Harvey Babb]

10 minutes ago, waterskier_1 said:

This is NOT True.  All our coaches use 50 Amps at 220 (or 230) VAC.  Simply plugging into a 230 VAC, 30 Amp outlet would not necessarily cause any problems.  Granted, there might not (depending on the 230 VAC, 30 Amp outlet used) have a separate ground and neutral.  What really matters is how he connected (adapted) the Dryer Outlet to his coach power plug.  

 

Yes, you most certainly can cause significant damage just by plugging into 230 volts WITH NO NEUTRAL. What this does is put roughly 1/2 of the devices in the coach in series with the other half and apply 230 volts to the lot. What this means is that the voltage that appears on any 120 volt device CAN BE as much as 230 volts. If the water heater or refrigerator happens to be on, whatever is on the other group will see nearly the entire 230 volts. 

With luck the transfer switch will fry before it pulls in and kills a bunch of other stuff, but the fact that dryer was hit would indicate that the the transfer switch DID pull in and apply voltage to the system. 

I have been the troubleshooter in two homes where loss of neutral occurred (both times when crimped connections in the meter loop corroded and burned up) and in both cases appliances were damaged. One was not as severe as the other because the ground connection kept the voltage partially in check. In the other case the bonding screw had been left out of the main panel so the appliances took the full brunt of the overload.

[waterskier_1]

27 minutes ago, Harvey Babb said:

Yes, you most certainly can cause significant damage just by plugging into 230 volts WITH NO NEUTRAL. What this does is put roughly 1/2 of the devices in the coach in series with the other half and apply 230 volts to the lot. What this means is that the voltage that appears on any 120 volt device CAN BE as much as 230 volts. If the water heater or refrigerator happens to be on, whatever is on the other group will see nearly the entire 230 volts. 

 

You are correct, if he used a 3-wire 220 30 Amp connector and did not wire the neutral.  But there are also 220 V, 30 Amp 4-wire connectors that DO have a neutral and ground.  My real point is that all our coaches use 220 (or 230 or 240) volts when on 50 Amp service.  If someone had a 220 Volt 4-wire 30 Amp connection, no damage would occur, you would just be limited to 60 Amps total versus 100 Amps.  

 

FIY NEC requires 4-wire 220 volt outlets for dryers since 1996.