Generator 120v relays SPARKING BAD!!!!

[jwrape]

I just replaced both of these Generator 120v relays because one didn't work and the other was sparking. I figure out that the one on the left only sparks when the Salon A/C unit comes on. There are a few times when it settles down and works correctly, but most of the time it sparks like a fireworks display as shown in the video here.
http://www.youtube.com/watch?v=Tg2lnCnJQNw&list=UU9CT249I05DyxqKD1RpYfpQ&feature=share

I am wondering if there is an upgrade from these relays to something less "Sparky"
I don't know why the front A/C unit does this on the Generator, it works perfectly on shore power.

[waybomb]

The contacts are coming apart and recontacting - probably a loss of current to the coil because of excessive AC current draw at start up.

I would re-tighten every electrical connection in the AC circuit (disconnect and lock out the electric first!). All the way in coming power line all the way to the AC unit and on to the water pump.

Does the AC unit use a starting capacitor? That would be my next bet as something failing. If you don't know how to check a capacitor - DO NOT TOUCH IT! It can store a nice jolt. Have somebody check it.

[jwrape]

The contacts are coming apart and recontacting - probably a loss of current to the coil because of excessive AC current draw at start up.

I would re-tighten every electrical connection in the AC circuit (disconnect and lock out the electric first!). All the way in coming power line all the way to the AC unit and on to the water pump.

Does the AC unit use a starting capacitor? That would be my next bet as something failing. If you don't know how to check a capacitor - DO NOT TOUCH IT! It can store a nice jolt. Have somebody check it.

I will re-check the connections but I am certain that I tightened everything down and it was burnt up as if it was doing that before AND I have another burnt one in a box that came with the boat, so I would lean towards the start up capacitor. Do you know where it would be located? On the Unit?

[waybomb]

I would guess in the control box attached to or off to the side of the AC unit.

Check those solderless connectors people like to use - yank on the wires while the connector is still screwed on.

[jwrape]

I would guess in the control box attached to or off to the side of the AC unit.

Check those solderless connectors people like to use - yank on the wires while the connector is still screwed on.

Yea I hate those too. They always come loose

[MissWhit's]

jwrape, I watched your video and what is happening is the control voltage to the relay does not have enough power to fully engage the contact and hold. We express this power in wattage which is voltage time current. Place a meter (I prefer the old style needle meter and not a digital for this test) across the coil energizing connections and watch what is happening when it is told to energize. On the side of the relay coil body will be the voltage rating for the coil and the amount of HP the contacts are rated for. The voltage should not drop below 10% of the rated coil voltage or you will have the problem seen. I can not troubleshoot for you why the voltage is dropping so you will have to figure this out along with some local help if needed. Good luck. MissWhit's

[MissWhit's]

Oh, I forgot to mention something important. Wire guage size and length can cause this problem also if the voltage is dropping from the source of power. MissWhit's

[jwrape]

Oh, I forgot to mention something important. Wire guage size and length can cause this problem also if the voltage is dropping from the source of power. MissWhit's

Ok, I will have to search and troubleshoot it. It's funny cause regular shore power works fine but Generator does this and it draws quite a bit of current. I might have to have a local Marine Mechanic look at it. I hate getting near the capacitor since I have had those spark in front of me before.

[waybomb]

That's a clue - when checking connections, check all the power connections in the genny j-box. Have you checked the brushes on the genny? When the ac starts, do you hear the change in load from the genny; is it reacting quickly enough? Do you have access to a VOM? If so, you may want to check voltage to the ac unit on shore power vs genny power at ac start.

[jwrape]

That's a clue - when checking connections, check all the power connections in the genny j-box. Have you checked the brushes on the genny? When the ac starts, do you hear the change in load from the genny; is it reacting quickly enough? Do you have access to a VOM? If so, you may want to check voltage to the ac unit on shore power vs genny power at ac start.

I have no idea about all that. I know the motor side of things but the generator side of things is a little beyond my knowledge.
I do know the Genny has 450 hrs on it, it was installed about 3 years ago, it's a NICE Kohler 7kw... Anything else about it, I don't know. It runs like a sewing machine and you can hardly tell it has a load on it at all except the gauges move. You can hear it in the video that it handles the load well.

My old 6.5kw Onan SUCKED! It was loud and hated a double A/C load. I was happy to see this one was a Kohler.

Here is a Video of the Generator itself
http://www.youtube.com/watch?v=9VPBeS-BIBk&list=UU9CT249I05DyxqKD1RpYfpQ&feature=share