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No Power on L1
#1
Tonight I lost power to the fridge, 120 V vanity lights, several outlets, etc.  The L1 voltmeter above driver seat shows 0.


I traced the problem to the generator/shore switch in the rear closet.  I have 120 on each leg and 240 across the legs on coming into the Cutler-Hammer C65FNF360.  But going out only L2 has power.

I toggled the shore/generator switch back and fourth a couple of times to see if it would reset with something simple, it didn't.

It is -9 here now and the generator won't start so I can't see if that gives me power on both legs coming out of the transfer switch.

What are your thoughts?

I'll probably direct wire to bypass the switch in the morning for a temporary fix.
Doug and Cathy Musick
Coach 370
1994, 45', non-slide
DD60, Allison 741
#2
Just a wild guess because I’m no expert. How about resetting a inverter?  This situation would happen on my old TS coach and I’d have to crawl under and reset an inverter that had tripped. Again Just a guess.
Dale
2013 Newell #1472
#3
Dale,

Who needs a frig when it's -9? I am sorry I should not have said that when I am parked in Florida! Hope you have a sense of humor.
Okay, now I don't have a coach exactly like yours, but I do have a degree in electrical engineering - ha ha And, I slept in a Newell last night...

So, my suggestion would be to temporarily disconnect from power and remove the cover on your transfer switch. You should see two black cubes right up against each other. When they are working correctly, only one is energized. They are probably both mechanically and electrically interlocked in an effort to be sure both can never be closed at the same time. In the center of each there should be a small rectangular projection that is connected to the portion of the contactor that moves when it is energized and de-energized. At this point they should both be de-energized of course and both protruding upward from their case. If you have some spray lube that is safe for plastic you could try some of that and then work the buttons back and forth to see if you can free things up. If you try to push both down at the same time they should resist. But, if you ease pressure on one it should allow the other to be pushed all the way down. Working them back and forth may do the trick. Again, be sure there is no power on the coach when you do this. If you feel comfortable with a voltmeter you can leave the cover off and energize the coach. This will allow you to check the voltage on each terminal and visually see the contactor is fully energized. Russ
Russ White
#530
1999 45' Double Slide - Factory upgrade 2004
#4
Doug,

In the conditions you are in. I would direct wire around the contactor. Of course you know to unplug, but also turn off the inverter to prevent back feeding the coach side.

I use a belt and suspenders approach with electricity. I ALWAYS use a voltmeter to check something before I touch it.

You can noodle out the contactor issue when it warms up.
Richard and Rhonda Entrekin
99 Newell, 512
Subaru Outback Toad
Inverness, FL (when we're home Cool )
#5
Hi, do you have a fw-x240? outback transformer? I lost L1 and it was a faulty breaker and what its job is to balance the current draw if you have outback inverters, mine is located in the same bay as the inverters and 120volt distribution block
#1218 in Europe based in the UK
#6
Ok, tried manually exercising the switch with no benefit. Picked up some heavy duty set screw wire connector lugs to splice the wires and bypass the switch.

As to a permanent fix I haven't found a Cutler-Hammer one yet. Newell has an Eaton one which is a little different they said should work. I'll follow-up with them tomorrow. Better yet this would be a good opportunity to switch to a style with surge protection and/or auto switching. If I were to upgrade my transfer switch set up what do you recommend?
Doug and Cathy Musick
Coach 370
1994, 45', non-slide
DD60, Allison 741
#7
Perhaps Richard or Gen Man could review this before you take action....

Eaton purchased Cutler Hammer in 1974, but the packaging reflected the more commonly know Cutler Hammer logo until just a few years ago.The C65FNF360 is actually a 60 amp 3 pole 480 volt reversing contactor, mechanically and electrically interlocked with coils to be actuated by your rv battery power. The part number does not call out the actuating coil data, and since I own a very old Newell, I am just guessing that the coil control voltage is 12 volt dc for your coach, and the contactor has two of them. We know that the contactor is "making and breaking" because you are getting one leg of power . One of the three contacts in one side is not making contact. The contact could be bad, or the coil may not be able to close the contact any longer. These contactors are rated for hundreds of thousands of operations,. It is a very simple project to examine the contactor ( after removing all sources of power) If you wanted to repair the contactor you have and put it back in service, it is a very simple job of just a few minutes, a screwdriver and a wrench or you could have an industrial electrician do it for you. The contact is just a piece of silver coated metal and a spring. Here is a supplier of replacement contacts, and replacement coils for Cutler Hammer/Eaton contactors

Sales@lancocontacts.com
940-565-6545
Lancocontacts.com
Guy & Sue
1984 Classic 40' #59
#8
I agree one of the contacts in the contactor is not making the circuit. Yes, one could replace the contactor. You could also get access to the actual contact and clean it up a bit. If you do that, it will work for a while, but my experience is that once the contact is compromised, it is a short time before it stops working again. Way back, all instrument techs carried a burnishing tool with them. It was used to work harden the surface of the contact to make it last longer.

My guess is that the combination of cold weather requiring extra heaters in the coach drawing increased amperage, low voltage on the grid because everyone else is doing the same, and the cold making the contactor old and creaky like me all contributed to the contacts burning up.

Once Doug has tried the Russ suggestions to exercise it, if it didn’t come back to life, I am hard wiring until it is warm enough to comfortably work on it. Then I am replacing the entire Xfer switch. I upsized mine to 90 amp just for overkill. That switch takes a beating.

While we are thrashing this subject, it is a good time to caution about switching from generator to pedestal under load, or vice versa. It absolutely wreaks havoc with the transfer switch. As one set of contacts open and the other set closes, an intense arc is created which burns up the contacts.
Richard and Rhonda Entrekin
99 Newell, 512
Subaru Outback Toad
Inverness, FL (when we're home Cool )
#9
I hard wired it yesterday.  Definitely waiting until better weather to tackle the problem.

Richard what did you use for the 90 amp switch?  Our local electric warehouse couldn't get the 60 amp Cutler-Hammer and every online hit showed unavailable.

When connecting shore power I always set the transfer switch to shore, shut off the pedastool breaker, plug in the cord and then turn on pedastool breaker. 

With the generator I haven't set the switch to generator first as I wanted to give the engine plenty of time to warm up before placing a load on it.  So it sounds like with the 120 shore power off I should move the transfer switch to generator before starting the generator?

I forgot to add in the original post that I lost L1 while just sitting connected to shore power, not when activating the switch.

The Newell voltmeter had shown decreasing V from about 122 V to about 118 V during this cold spell.  My max amp draw on either leg was around 40 and that was rare, normally it was in the 15 to 25 amp range.
Doug and Cathy Musick
Coach 370
1994, 45', non-slide
DD60, Allison 741
#10
Guy thanks for the link on the coils. I haven't pulled the switch out of the box yet to get a good look at things but if I diagnose a bad coil it may be an easy fix. But since I hadn't activated the coil when this happened, I'm guessing a bad contact.
Doug and Cathy Musick
Coach 370
1994, 45', non-slide
DD60, Allison 741


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