Transfer Switch Problem While Travelling

[Romeo]

Here we go again... problems while travelling.

Transfer switch partially zapped. One leg of shore pwr contactor toast.

Pulled into Whiskey Flats (Nevada) for the night. Plugged into the 50 amp pedestal... wife watching EMS panel... she saw a "over temp" warning (red light). I went back to the transfer switch and felt the switch housing and found that it was burning hot... fiipped the 50 amp breaker at the park pedestal. By this time the box began to crinkle from overheating. I opened the switch box and found that one output leg of the shore power contactor was burnt, melted insulation. Without the transfer switch I had no generator power or park pedestal power. I had the park check the 50 amp socket for proper voltages and both 120 legs check good.

Fortunately, I was able to get a local gold mine electrician to help me locate the problem and, hopefully a solution to get power for the evening. It appears that the one leg of the shore pwr contactor failed for some reason and is now toast.

We disconnected the bad leg from the house circuit and were able to get 120 VAC on the good contactor leg to run the air cond's, microware, and other necessary systems so we may be ok until we get back to civilization.

HOWEVER... I now notice that while connected to 50 amp, 120 VAC via the one leg, I an not seeing that the batteries are being charged, which could be a big problem in the morning.

Need help with this question: Could the battery charger be using the disconnected leg of the contactor?

What makes me think about this is that the electrician stated that he could find nothing in the coach that runs on 240v so he figured that the other 120v leg maybe powering some of the 120v circuits... not sure how I would check that out (thinking about it).

I'll post this... hoping for some help and think about how to check for lack of power the the battery charger. If this turns out to be true, I need to figure out how to charge my batteries from shore power.

I cannot run the generator since the transfer switch does not appear to be working with the toasted contactor leg disconnected.

[Dtwallace]

Try to find if you have a reset button popped on your inverter/charger. I'm thinking although the plug is a 220VAC 5amp plug, It's only wired to one side to give you 110VAC.

It sounds like your transfer switch was sticking and not fully releasing the contacts on one leg.

This would have caused a differential in frequency from two inputs at one time, building heat and farther melt down of the connections/contacts.

If this was the only issue, replacing the transfer switch will bring all back to normal. I think you caught it in time before further damage was done.

Best of luck, Please keep us informed.
DTW

[shiggs68]

The split or balance of your 120vac circuits can usually be found by looking at your breaker box. You will have a ganged pair of 50amp breaker with each sides sub-breakers on either side or down the row right/left.

Unless, your electrician disconnected the bad leg in your transfer switch, I would not use it until
Fixed correctly. You may have a dangerous safety/fire issue. Not something to treat casually!


Sent from my iPad using iRV2 - RV Forum
TravellingRVDoctor, LLC

[Romeo]

"Try to find if you have a reset button popped on your inverter/charger."

Inverter/charger online and appears to be working, but batts not charging.

"Unless, your electrician disconnected the bad leg in your transfer switch, I would not use it...

As I mentioned, the electrician did disconnect the bad leg so we should be ok there.

I did find that the bedroom A/C is not working, so I think that we were correct in that each leg of the 50 amp circuit was for supplying 120v to two different sections of the coach.

["007"]

Your shore line is split in TS to your load center which has two sides in it, AC's would normally be placed on one of the sides of load center not on same side.
Its happened they were put on same side of load center causing a overload.

Transfer Switch Diagrams

New TS's

Links found here.

May want to check the circuit breaker in load center for AC not working.

[Rotten-Red]

Originally Posted by Romeo

Here we go again... problems while travelling.

Transfer switch partially zapped. One leg of shore pwr contactor toast.

Pulled into Whiskey Flats (Nevada) for the night. Plugged into the 50 amp pedestal... wife watching EMS panel... she saw a "over temp" warning (red light). I went back to the transfer switch and felt the switch housing and found that it was burning hot... fiipped the 50 amp breaker at the park pedestal. By this time the box began to crinkle from overheating. I opened the switch box and found that one output leg of the shore power contactor was burnt, melted insulation. Without the transfer switch I had no generator power or park pedestal power. I had the park check the 50 amp socket for proper voltages and both 120 legs check good.

Fortunately, I was able to get a local gold mine electrician to help me locate the problem and, hopefully a solution to get power for the evening. It appears that the one leg of the shore pwr contactor failed for some reason and is now toast.

We disconnected the bad leg from the house circuit and were able to get 120 VAC on the good contactor leg to run the air cond's, microware, and other necessary systems so we may be ok until we get back to civilization.

HOWEVER... I now notice that while connected to 50 amp, 120 VAC via the one leg, I an not seeing that the batteries are being charged, which could be a big problem in the morning.

Need help with this question: Could the battery charger be using the disconnected leg of the contactor?

What makes me think about this is that the electrician stated that he could find nothing in the coach that runs on 240v so he figured that the other 120v leg maybe powering some of the 120v circuits... not sure how I would check that out (thinking about it).

I'll post this... hoping for some help and think about how to check for lack of power the the battery charger. If this turns out to be true, I need to figure out how to charge my batteries from shore power.

I cannot run the generator since the transfer switch does not appear to be working with the toasted contactor leg disconnected.

Romeo,

From your description of the problem it sounds that you need a new transfer switch which probably isn't available in your remote location.

My solution would be since you have to remove the transfer switch to replace it anyway, I'd remove it and go to a hardware store or home center and buy 2 female 50 amp range receptacles, and 1 male range plug. Home kitchen range plugs are the same plug used in your RV on the 50 amp shore power cord.

On the end of your shore power cord attach one of the female receptacles. On the end of your generator wires attach the other female receptacle. On the end of the wires going from your transfer switch to the MH main box attach the male plug.

Now when you want to use shore power just plug into the shore power plug receptacle, when you want to use generator power plug into the generator plug receptacle.

This will get you back in service. You can even complete your trip and deal with the transfer switch when you get back home. It's really not even that big a inconvenience not having the transfer switch. When you unplug from shore power in the morning to leave campground, just plug into generator plug at the same time. Then during day if you need gen power for A/C's or whatever you'll all ready be set to go.

[Jim T.]

Originally Posted by Rotten-Red

Romeo,

From your description of the problem it sounds that you need a new transfer switch which probably isn't available in your remote location.

My solution would be since you have to remove the transfer switch to replace it anyway, I'd remove it and go to a hardware store or home center and buy 2 female 50 amp range receptacles, and 1 male range plug. Home kitchen range plugs are the same plug used in your RV on the 50 amp shore power cord.

On the end of your shore power cord attach one of the female receptacles. On the end of your generator wires attach the other female receptacle. On the end of the wires going from your transfer switch to the MH main box attach the male plug.

Now when you want to use shore power just plug into the shore power plug receptacle, when you want to use generator power plug into the generator plug receptacle.

This will get you back in service. You can even complete your trip and deal with the transfer switch when you get back home. It's really not even that big a inconvenience not having the transfer switch. When you unplug from shore power in the morning to leave campground, just plug into generator plug at the same time. Then during day if you need gen power for A/C's or whatever you'll all ready be set to go.

That's a GREAT tip!!

I'm going to copy & save it on my Notes app. Hope I never need to use it though! 😍


Jim & Shirley & Abbie (Scottie)
2013 Newmar Canyon Star 3911
2005 Dodge Grand Caravan

[Romeo]

Originally Posted by Rotten-Red

Romeo,

From your description of the problem it sounds that you need a new transfer switch which probably isn't available in your remote location.

My solution would be since you have to remove the transfer switch to replace it anyway, I'd remove it and go to a hardware store or home center and buy 2 female 50 amp range receptacles, and 1 male range plug. Home kitchen range plugs are the same plug used in your RV on the 50 amp shore power cord.

On the end of your shore power cord attach one of the female receptacles. On the end of your generator wires attach the other female receptacle. On the end of the wires going from your transfer switch to the MH main box attach the male plug.

Now when you want to use shore power just plug into the shore power plug receptacle, when you want to use generator power plug into the generator plug receptacle.

This will get you back in service. You can even complete your trip and deal with the transfer switch when you get back home. It's really not even that big a inconvenience not having the transfer switch. When you unplug from shore power in the morning to leave campground, just plug into generator plug at the same time. Then during day if you need gen power for A/C's or whatever you'll all ready be set to go.

Ah yes... we are on the same page. I have been looking everything over and came to the same conclusion, but in a different way. I like your method.

I was thinking of just bypassing the contactors and making sure not to run the generator when shore pwr was on, and visa-versa. I was leery of doing that, however, since I am not sure of any problems in the wiring on the down-stream side of the contactors where the first two inches of insulation was melted on the one bad leg.

My biggest concern this a.m. is getting the house batteries charged since I am drawing them down to nothing. Just talked to Newmar about how the house wiring is connected and found that it is right that some of the house AC is on one leg of the 50 amp and some one the other leg of the 50 amp. Newmar said that I am not charging the batteries because one leg of the 50 amp is disconnected, as I thought. So, apparently it takes both 50 amp legs to run the charger above 12 vdc, ie. 13.5 vdc.

I do realize that once I hit the road the engine alternator will charge the house batteries... if I haven't ruined them overnight.

[Rotten-Red]

Originally Posted by Romeo

Ah yes... we are on the same page. I have been looking everything over and came to the same conclusion, but in a different way. I like your method.

I was thinking of just bypassing the contactors and making sure not to run the generator when shore pwr was on, and visa-versa. I was leery of doing that, however, since I am not sure of any problems in the wiring on the down-stream side of the contactors where the first two inches of insulation was melted on the one bad leg.

My biggest concern this a.m. is getting the house batteries charged since I am drawing them down to nothing. Just talked to Newmar about how the house wiring is connected and found that it is right that some of the house AC is on one leg of the 50 amp and some one the other leg of the 50 amp. Newmar said that I am not charging the batteries because one leg of the 50 amp is disconnected, as I thought. So, apparently it takes both 50 amp legs to run the charger above 12 vdc, ie. 13.5 vdc.

I do realize that once I hit the road the engine alternator will charge the house batteries... if I haven't ruined them overnight.

I'm not sure you would need power to both legs to make the charger work. I think what Newmar was talking about was you didn't have power to the leg that feeds the charger.

If your not moving today and all you want to do is get the batteries charged you could probably switch the two hot wires in the transfer switch so that your powering the other leg which has the charger on it. But then you would loose power to whatever you have power to now.

[Romeo]

Originally Posted by Rotten-Red

I'm not sure you would need power to both legs to make the charger work. I think what Newmar was talking about was you didn't have power to the leg that feeds the charger.

If your not moving today and all you want to do is get the batteries charged you could probably switch the two hot wires in the transfer switch so that your powering the other leg which has the charger on it. But then you would loose power to whatever you have power to now.

Good point, I forgot that was what I figured last night at about 2:00am. I think your right. Well, except... now that I think about it; the charger seems to be charging at 12vdc according to the EMS panel, which isn't enought to actually charge the batteries.

Better just hit the road and let the alternator do the charging.

[Dutch Star Don]

Romeo.....I know your on the road, but I would simply order a new transfer switch and have it overnighted. Have it delivered to the campground, post office or local business.

Rotten Red's repair is the way to go, but if you're willing to do all of that, why not just replace the transfer switch (same wiring work). You can throw a cheap battery charger on your coach until the transfer switch arrives. Either buy one at a auto parts store or borrow one from someone for a few days.

[Romeo]

Originally Posted by Dutch Star Don

Romeo.....I know your on the road, but I would simply order a new transfer switch and have it overnighted. Have it delivered to the campground, post office or local business.

Rotten Red's repair is the way to go, but if you're willing to do all of that, why not just replace the transfer switch (same wiring work). You can throw a cheap battery charger on your coach until the transfer switch arrives. Either buy one at a auto parts store or borrow one from someone for a few days.

Yes, have been considering that. I have heard on the forum that some have said the Todd Engin.eering ATS was not a very well built unit. Have heard several say that they thought the Progressive PD2400 series was a good switch.

I did search the internet for prices and find that one can get a PD24v without surge protection (240v, 50 amp) for around $130.

Since we needed both A/C's for the night or two in Reno, and that I was concerend about the batteries not charging while "plugged in", I decided to get someone local (in Reno) to take a look and verify my options. I got Scotty from Scotty's Mobil RV service and he came out as soon as we parked. He agreed with me that the quick fix was to bypass the transfer switch (ATS) for a temporary, cheaper fix, which the did (and which I could have done if I had the guts). In retrospect, I should have had the electrician in Whiskey Flats do that for me for the same cost that I paid him, .... and had to re-pay for today! Oh well that's the price of not thinking clearly when stressed out, and the price for a feeling of comfort having not done it myself. So... anyone that is gaining knowledge from this post, and will do what we have discussed, on their own, can send contributions to me to help defray the $105 that I paid today and the $80 donation that I am sending to the mining electrician that came out after-hours last night to help get some A/c running, and the cost that I will incur to re-do it all when I install a new ATS. Of course I now know what to do on my own if ever need-be.

Ok, back to the subject at hand; I am searching for a $130 ATS that can be sent to me here in Reno, cheaply, and that Scotty will install for about an hour of labor... sounds like about another $$230 without shipping. Or I could wait a week and have it sent to home and install it myself.... don't know... thinking.

Oh, BTW... just for the record and for anyone that needs to do emergency fixes to the ATS; with one leg of the 240 vac, 50 amp contactor zapped and disconnected, as I have stated there was only one A/C being supplied with AC and the 13+ vdc to charge the batteries was not available, only about 12 vdc was available for charging. Once Scotty bypassed the ATS and supplied 240 vdc from pedestal to house wiring both A/C units worked and the charging circuit was supplying 13+ vdc to charge the batteries. So I have learned that there is no device in the coach that uses 240 vac; the 240 vac is used to provide two different 120 vac circuits to various devices in the coach (open to any corrections by knowledgeable individuals).

Had I done it myself I would have mistakenly tied the generator and the pedestal wiring together, bypassing the ATS and mistakenly thinking that all I would have to be concerned with is NOT plugging in the pedestal pwr while the generator was running. Scotty pointed out to me that with all three circuits tied together the pedestal pwr would feed back into the generator. No telling what that would have done to the generator. So apparently it is important to isolate the generator from the incomming 240vac from the pedestal, and that is one of the functions that the ATS performs.

[tbbg II]

I had a similar situation during our recent trip. When I plugged into shore power one evening, nothing happened, at least not for long. After some choice words and a lot of investigation, I found the ATS would not switch to shore power. My quick fix was simply to bypass the switch with some large wire nuts. I don't recommend this approach, but I was comforable with it. Turns out I also had a bad Heart Interface charger, but that is another story. I did a fair amount of research into ATS's and eventually decided to go with ESCO. They also make the LYGHT brand, which is what went bad. Anyway, I called Elkart Supply Company and learned my ATS was too old to be serviced. They now have two types of switches, a contacter type and a relay type. I honestly don't know the difference, but ended up with the newer version. After many questions regarding the differences between the two designs, the CS representative I spoke with admitted the older design hums alot! He said the components are no longer as good as they once were. My old switch didn't hum even when it worked, but he assured me a new one would. The prices they post on their site are outrageous, but they discount to the price found on eBay (almost). The replacement was rather difficult as one pretty much needs to climb into the electrical bay and then fight with the heavy guage wires to get them into the right position. But at the end of the day, the replacement worked fine. I got it in two days. Had I known this I would have had them ship to one of the campgrounds we visited, like I did for the new inverter/charger.

[Scottybdivin]

Yes, Big Blue wire nuts are good for up to #6 wire. Secure them with electrical tape for vibration resistance. It would be an easy temporary fix, to get you by.