| Author |
Message |
William Guire (Will) (216.82.156.188)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Friday, October 17, 2003 - 8:10 pm: | |
I have an ESCO 50 amp auto transfer switch. I got it used. I installed it as shown in it's diagram. It switches shore power fine. When I disconnect shore power and start the generator, there is a thirty second delay then I can hear the switch relay close. But then it instantly opens and continues closing and opening non stop. What could cause this? I checked the generator output, which is 125 volt on each leg. The generator is an Onan NH6.5. It has a 20 amp and 30 amp output, which I've tried togather into the switch and as separate legs. Has anyone encounterd this problem? Maybe I got a bad switch, but I want to try and make it work since the place I purchased it is quite far away.
Any suggestions would be appreciated.
Thanks
Will
83 TMC MC9 |
two dogs (66.90.212.24)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Friday, October 17, 2003 - 8:22 pm: | |
"which I've tied together"..doesn't sound right, |
two dogs (66.90.212.24)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Friday, October 17, 2003 - 8:24 pm: | |
sorry misread it |
Richard Bowyer (Drivingmisslazy) (24.196.191.70)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Friday, October 17, 2003 - 11:42 pm: | |
Check your diagram again very closely. Most ATS's are not designed to switch 240/120 volt genset outputs, which I suspect you have based on your description. The gen set can probably be re-connected for straight 120 volt output. Check your genset manual. If no resolution, come back to the board and some of us will try and help you.
Richard |
Quest (198.29.191.148)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Saturday, October 18, 2003 - 1:18 pm: | |
It sound like you have the genset connected to the wrong sensor, when the throw-over operaties, it loses the sense and opens again. It sounds like a simple wiring problem. Look your notes over and see how you wired it. |
Jim Ashworth (Jimnh) (172.137.9.37)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Saturday, October 18, 2003 - 6:23 pm: | |
It's not the genset field wiring, it's the interlock wiring between the two contactors. Check the contactor auxiliary contacts wiring. These are snapped onto the sides of the contactors and operate to ensure that if one contactor is engaged the other can't be energized.
Jim |
William Guire (Will) (216.82.156.149)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Saturday, October 18, 2003 - 10:23 pm: | |
I will check the wiring again first thing in the morning. I have tried most combinations with the wires coming in from the generator. The contactor wires sound promising. One clue might be that there is no delay before the shore power is put through when connected. As soon as I connect shore power I hear the switch close and there is power to the main breaker box. I don't know if there is supposed to be a delay on that side or just the generator side.
Thanks
Will |
Jim Ashworth (Jimnh) (172.175.59.250)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Sunday, October 19, 2003 - 9:24 am: | |
The delay is only on the genset side to allow the generator engine to stabilize and have oil circulating for a while before a load is placed on it.
Jim |
William Guire (Will) (216.82.156.185)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Sunday, October 19, 2003 - 10:18 pm: | |
Well, I've checked all the wiring, tried all combinations and nothing works. As far as contactor wires inside, the switches are connected directly to a circuit board, so there little I can do with that. The final thing I tried was to disconnect all inputs and outputs, then connected shore power to the input side that usually has the generator on it. It did the same thing, opened and closed rapidly. I guess I'll give it up as a bad ATS and wire a couple outlets and a plug for now.
Thanks for the suggestions.
Will |
Dale MC8 (66.81.142.200)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Sunday, October 19, 2003 - 10:38 pm: | |
Will, why don't you call ESCO and talk to a tech there? I also have one of these switches that I got for free and wanted to use as you do. Called and talked to someone that really sounded like he knew what he was talking about, was having a dialog with Xantech on that very subject. Unfortunately, I neglected to write down his name and when I called back noone knew who or what I was talking about. I think if I had been better prepared with details that were needed I would have gotten the info I needed. Or am I just TOO innocent?
Dale MC8 |
Richard Bowyer (Drivingmisslazy) (24.196.191.70)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Sunday, October 19, 2003 - 11:09 pm: | |
You say it switches shore power fine. What voltage is the shore power? Is it a 30 amp 120 volt service or is it 240/120 volt 50 amp service?
Richard |
William Guire (Will) (216.82.156.185)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Sunday, October 19, 2003 - 11:49 pm: | |
Dale,
I think I will try calling ESCO before I give up. You wouldn't have their number, would you? It isn't on the device.
Richard,
The shore power is wired for 50 amp 240 volt but it has adapters and is hooked to 20 amp 120 volt right now. It works fine when hooked to the shore input but does not work when hooked to the genset input of the ATS. Thats why I think the switch on the genset side is bad.
Will |
Richard Bowyer (Drivingmisslazy) (24.196.191.70)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Monday, October 20, 2003 - 8:16 am: | |
Will, I really do not think so. It sounds like you are trying to switch between a 120 volt source (shore power) and a 240 volt source (genset power).
Richard |
Jim Ashworth (Jimnh) (172.171.194.96)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Monday, October 20, 2003 - 9:29 am: | |
Richard- That really shouldn't matter since the poles are separate and only one pole is used to energize the coil to close the contactor. Since on 120v, the two poles are connected through the plug adapter from 50a/240v to 120v the coil still sees the voltage to energize the coil.
Will- Try removing the circuit board and wiring direct to bypass the circuit board connections to the coil terminals. It should be obvious which wires the circuit board is using. I have done this on a Todd xfer switch because they are no longer in business and the circuit boards are not available.
The auxiliary contacts should be normally closed and the shore contactor auxiliary should be wired to the genset contactor and the genset auxiliary should be wired to the shore contactor. This prevents the genset coil from being energized when the shore contactor is closed and visa versa. These things are not complex electronic devices and wiring is easy to trace and troubleshoot.
Jim |
William Guire (Will) (216.82.156.180)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Monday, October 20, 2003 - 10:27 am: | |
Richard,
The genset is only putting out 120 volt. I thought it was 120/240 but it isn't. It has two black wires, one white and one green. If I measure between each black and white, I get 120 volts. When I measure between the two blacks, I get 0 volts. So I guess the two power outputs are the same phase. So it's only 120 volt.
Jim,
I guess I'll have to decide if I should go ahead and tear into the thing or wait and return it and try a different one. If you can bypass the circuit board and still have the switch work, what is the function of the circuit board? Does it cause the delay for the generator to warm up? Anything else?
Thanks
Will |
Dale MC8 (66.81.142.197)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Monday, October 20, 2003 - 12:33 pm: | |
Will, yeah I do have the phone number, but it is in the bus, about 5-6 miles away. I'll get it today and post it here for you.
Dale MC8 |
Doug Dickinson (Dougd470) (65.161.188.11)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Monday, October 20, 2003 - 1:19 pm: | |
Re the voltage wiring issue - some 120VAC only gen sets (frequently RV type gen sets) will have 2 hot wires - one with a breaker for 30 amps and one for 20 amps. On my Honda RV unit - these are actually tied together in the unit and split at the circuit breaker again. I don't know why, but they are. |
Dale MC8 (66.81.131.204)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Monday, October 20, 2003 - 7:21 pm: | |
Will, the phone number for ESCO (Elkhart Supply COrp) is: 800-456-3726. Good luck and let us know the outcome.
Dale MC8 |
William Guire (Will) (216.82.156.160)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Tuesday, October 21, 2003 - 4:05 pm: | |
Dale,
I gave ESCO a call and the tech there was helpful, although he confirmed what Jim thought, that the circuit board probably has a bad component. So I've wired around it for now and will swap the bad ATS for another when I'm back up near where I got it.
Thanks for everyones help.
Will
83 TMC MC9 |