Surge Guard Model 41260 Transfer Switch Problem

My Surge Guard Transfer Switch has started pulsing when connected to 50A service when I turn on the AC's, either one or both AC's. The power connects and runs for a while then starts this pulsing of the contactor than energizes with line power. It has happened at 3 different locations and the power checked good at all locations.
It finally did it this evening when connected to 30A service.
Seems like something on the control circuit that energized the contactor but everything looks good visually, just wondering if anyone else has ever experienced this type failure. This transfer switch was replaced about 18 months ago by Winnebago while the unit was under warranty for a different problem.

Awfully hot in Texas for no AC but at least this cold front is coming through and making it a bit more bearable.

Safe Travels,
David

Is this "pulsing" just noise, or do you actually lose and then regain power (the contacts open up, then close again)? Is it rapid or slow (slow would be several seconds or more). Does it do the same thing if you run the generator? If so, that suggests a control problem. If not, that suggests either the relays for shore power or perhaps the shore power wiring to the ATS.

Only happens on shore power that I have ever noticed. The power pulses off and on. I opened the ATS and the contactor for line power is pulsing at a rate of several cycles per second. Seems about as fast as the contactor will cycle.

I called TRC, the makers of Surge Guard Products and talked to their support person and got the distinct impression I was not unique and it was a control board problem. He indicated I should be able to get a replacement control board as a warranty replacement, but I had to talk to someone else in their organization. I finally reached her Friday Afternoon and she wanted a copy of the Repair Order where Winnebago replaced it. I sent that to her and have not heard back. So I hope they come through and that is indeed the fix.

I think it is heat related as it only happens when the AC's first kick in and not always. This past few days they run fine for an hour or so then it starts the pulsing when they cycle back on. Seems much better on 30A service, I am not sure why. I opened the ATS box and left it open and stayed on 30A connection and is has so far not occurred again but with the cold front I am now running the heat pump instead of the AC and running it much shorter cycles. Just hope I can make it until a part hopefully shows up.

Thanks for your feedback,
David

Thanks for the feedback, David.

I've been running a TRC #40250 ATS/power monitor for 4 years now and no problems like that, but it is prone to humming at times. Sometimes slight, sometimes loud, but mostly quiet (no hum).  I've never been able to pinpoint the electrical characteristics that cause the hum, however.

Mine made clicking noise with power reduction as well, on shore power..last day of warranty IN the Lazydays campground! Replaced! FYI about $260 on amazon.com.

Hum is caused because of a coil or transformer with loose windings and USUALLY an iron core made up of "Leaves" which are varnished together, as the thing gets older the varnish fails and the leaves can move a bit causing HUM.

In the case of the Surge Guard, that "Coil" would be on the power contactors  (Big honking relay)  As that is how many of them are made.

Hum is usually caused by loose iron laminations, not loose windings. The laminations are not normally varnished together. After winding the transformer, the entire thing is likely dipped in varnish. That's how we did it when I worked in a winding shop that would countless motors, generators, and transformers. But that was in the 60's.

It appears SurgeGuard is replacing the unit under warranty, supposedly shipped yesterday, waiting for waybill.
With the cover removed and a small fan blowing air on the unit it has behaved, but I am only running one AC as it seems to act up with heavier loads. I may try both AC's after I receive the replacement just just to see if the fan keeps it working with a heavier load - curious!
They offered a controlboard or a new unit, I elected the new unit even though it will be much more difficult and time consuming to replace. Since this one did all the contactor chattering under load I am not sure what shape the contactor is in for line power.
I am impressed they are warranting the unit even though it is over 2 years old, at least they are standing behind their product.
I expect the replacement on Friday.

Safe Travels,
David

Let us know how it plays out.

Replaced the ATS today, a moderately taxing job with the large gauge wiring and reaching inside a bay, but got her done.
Hooked the power cord back to a 50A plug and turned the breaker on and waited for the time out of the Surge Guard to restore coach power. When power came on, the ATS initially did not engage the line contactor, there was a fairly long delay - minute or two. When the power did come on, the line contactor on the ATS cycled on and off randomly for the next 15 minutes or so. I checked and verified wiring, checked power with DVM, checked all connections. I tapped on the control board and the two plugs on the board to see if I might have an intermittent connection. Nothing I did would cause the contactor to cycle, it seemed to just do it on its own schedule.

I tried loading the circuit with water heater, AC etc. and there did not seem to be a correlation to the contactor cycling. I turned off the Main Breakers in the coach to remove all load and the contactor still randomly cycled. With no load I left the power to the ATS on and the unit cycled a few more times while I was scratching my head and then it seemed to stop, no cycling. After waiting a few more minutes, I went back in the coach and turned the Mains on and started loading the ATS. I had all electrical loads on and nothing more happened, no more contactor cycling.
I left it with full load until the AC's were satisfied and started cycling and unit worked as I expected. So now I have buttoned the ATS case up and closed the bay hatch to let the ATS heat up to normal operating temp and see if it continues working properly. I am totally baffled by the series of events - makes no sense to me.
My biggest concern is do I trust it now? I plan to call their technical support person on Monday and relay to him the sequence of events and see what he thinks and if he has any reasonable explanation.
Any thoughts from anyone?

Safe Travels,
David

I guess I would not want to trust it. Too much risk that the eventual end of the cycling will be with it open rather than closed.

Since you replaced the entire ATS, it seems the problem is either the wiring in the coach (shore cord) or the power source. Is it a standard 50A outlet (240v/50A)? I know you said it did the same on multiple sources, but this is now a new ATS. Voltage measures OK across L1/L2 and each leg to neutral? How about the neutral wire on the shore cord plug? Maybe a nearly broken connection there? Does the voltage on each leg stay at 120v when the loads come on?

My 40250 has a normal power-delay built in, to make sure the a/c's have time to settle if they were on at the time of the switchover. Surge Guard calls this the F (Fleetwood) option, but I think they make it standard now.

I have an internal DVM plugged into an outlet in the coach which has always shown expected voltage, except when the contactor is actually open or chattering , as it did with the original ATS. The symptoms of the replacement ATS were totally different. It did not matter if there was any load or not, the line contactor would cycle on or off randomly. It never chattered or cycled quickly, shortest cycle time was probably 10 or 15 seconds, then it would either click on or off depending on which state it was previously in.
Checking all voltages at the ATS with a DVM they always measured as expected, never any variability like I would expect with an open or weak Neutral.
Also the coach has run all afternoon now without a recurrence of the ATS cycling. It was almost like the ATS was doing some type initial power up setup, which sounds bizarre but this entire episode has been weird. Also this ATS does have a 30 second delay for power connection.

Bizarre. Please let us know what TRC Surge Guard has to say.

Talked to TRC (SurgeGuard) this AM and they had little to suggest other than maybe something stuck in the contactor. Not really a confidence building response, but the unit has continued working as expected. I checked to make sure it switched over with generator and switched back when generator switched off and everything switched as expected.

I am still puzzled and will hang on to the old unit for a few days to make sure this one continues working properly.

Safe Travels,
David

The old one may only need a replacement relay, since its problem seemed to be just "chattering". You should be able to find the component if you hunt around online - TRC doesn't make special relays - they just assemble using standard components.

Had to move the MH today so disconnected power and unit sat for a while then re=parked and plugged back in. Both AC's started up and no issues. I am perplexed to explain or understand what happened but the unit continues to function normally.
I have to return the old unit as the replacement was a warranty replacement, so repairing it is not an option, although with my confidence in the new unit I wouldn't mind having a spare.

Thanks for all your help,
David

Maybe the initial relay clattering was the gremlins running away when faced with a brand new Surge Guard ATS?

Seems to have scared then into submission as all is still functioning as expected.

Safe Travels,
David

yoda2405 said:

My Surge Guard Transfer Switch has started pulsing when connected to 50A service when I turn on the AC's, either one or both AC's. The power connects and runs for a while then starts this pulsing of the contactor than energizes with line power. It has happened at 3 different locations and the power checked good at all locations.
It finally did it this evening when connected to 30A service.
Seems like something on the control circuit that energized the contactor but everything looks good visually, just wondering if anyone else has ever experienced this type failure. This transfer switch was replaced about 18 months ago by Winnebago while the unit was under warranty for a different problem.

Awfully hot in Texas for no AC but at least this cold front is coming through and making it a bit more bearable.

Safe Travels,
David

Click to expand...

New to this forum because I was looking for answers ..my shore power was randomly working but was clicking on and off for the most part ..I finally figured out all I had to do was re tourque all the terminals in the box has been working great every since ..make sure you disconnect all power and shut batteries off first

rv northwest said:

New to this forum because I was looking for answers ..my shore power was randomly working but was clicking on and off for the most part ..I finally figured out all I had to do was re tourque all the terminals in the box has been working great every since ..make sure you disconnect all power and shut batteries off first

Click to expand...

Perhaps you should start a new post. The one you attached yourself to is 9 years old.