802 tripping on overload

[spuddle]

Hi all, ive read several threads about this. Still trying to figure things out here. At about 2500 watts it starts tripping the overload, reading about 40% load on the gage. If i enable battleshort it will not trip, but the overload light turns on. And remains on.

Looking for some tips to try and rectify this. Is this the k8 relay (ci?) being dirty and just needs cleaned? I seem to see a lot of problems with this. And im kind of at a loss here. All switches look good, wires look good, ac ci switch seems to work fine. Overload resets when pushing the button and immediately reconnects when flip the switch.

Unit has 220 hours on it. I do live in a very humid environment as well

EDIT: And now after running for 13 hours it wouldn't shut down. I dont know if this is related. Had to use the off switch in the engine bay and wait for it to run out of fuel to shut down. The run switch did nothing but turn power off to the gauges.

TIA

 

[kloppk]

Check out this thread. Lots of good info on things to test to track down the cause of a false overload.
False Overload Issues

 

[spuddle]

Check out this thread. Lots of good info on things to test to track down the cause of a false overload.
False Overload Issues

Thank you. I am working through this thread now. Hopefully this will shine some light for me.

Any suggestions of why the unit wouldn't shut down? Or where to start looking?

 

[Guyfang]

One thing at a time. Sometimes you get lucky and both problems may get corrected for only one fault.

Is this set new to you? Have you ever seen it work right? For longer periods? Have you fixed anything of late? Are you using the TM's to troubleshoot?

 

[spuddle]

This is new to me. I have 2 of them. Only really played with this one so far. This is the first real load testing of it. I ran on the convenience plug for a few hours and never had an issue. This is the first time running off the terminal board.

They get fired up once a month at least and run for about 10-15 minutes, and i exercise the ci as ice read in here to make sure to do so they dont stick.

Was redoing my solar system, and has the house running off the gen just fine all day yesterday, then when got everything hooked back up and started charging batteries is when i started running into it tripping the overload. Started originally tripping around 4000 watts, then every time it tripped i had to keep reducing the load down to about 2000 before it stopped tripping, thats when i hit the battleshort and was able to crank it back up to around 4000.

Then the end of the night, i opened the ci, turned battleshort off and tried to shut it down, which the main switch did nothing. Havent started it today so far

EDIT: Yes i am using the plethora of manuals for these.

 

[Guyfang]

Do you have a load bank? Or something something you could use to load the gen set to rated load, besides the battery charging setup? If so, disconnect the battery charging set up. Hook something else up to the set and load the set to rated load. Will it run right?

Was redoing my solar system, and has the house running off the gen just fine all day yesterday, then when got everything hooked back up and started charging batteries is when i started running into it tripping the overload.

I say this, so that you can eliminate the possibility that something got hooked up wrong after the work on the solar system. Normally we would start telling you to clean the S8 switch with contact cleaner. That seems to be what helps out with most of the overload problems. But over the years I have found that when something worked before I did work on it, and didn't work later, I hooked up something wrong. Food for thought.

 

[spuddle]

Unfortunately, i do not have a load bank. Ive been wanting to get one for my 26kw diesel, but havent had the funds, nor would that work for these i dont think

 

[Guyfang]

Then maybe you need to try cleaning the S8 switch. That could also be your problem.

 

[2Pbfeet]

Unfortunately, i do not have a load bank. Ive been wanting to get one for my 26kw diesel, but havent had the funds, nor would that work for these i dont think

There's always rescuing/repurposing an old electric stove, or several electric dryers elements with new fans, or looking for some "scratch & dent" electric heaters. E.g. I rewired a 10kW heater with three elements to give me a DIY load bank with 1.6/3.3/4.9/6.6/10kW. Not as compact as a purpose built load bank, but it works. Total cost less than $100.

All the best, 2PbFeet

 

[spuddle]

There's always rescuing/repurposing an old electric stove, or several electric dryers elements with new fans, or looking for some "scratch & dent" electric heaters. E.g. I rewired a 10kW heater with three elements to give me a DIY load bank with 1.6/3.3/4.9/6.6/10kW. Not as compact as a purpose built load bank, but it works. Total cost less than $100.

All the best, 2PbFeet

Hey, idk why i have thought about that before. Thats actually a great idea. I do have some 1300/1500w milkhouse heaters. That would be exactly a load bank. Here i was thinking about something big and expensive. Thank you for bringing that up. I will have to give that a try.

I always try to load balance the generators tho, so question would be in 120/240 mode, that would be 2 heaters on one leg and 1 on the other for 4500 watts, thats a pretty big load imbalance. Is it going to be ok that way, or should i try to find something 240v to keep it balanced? Otherwise that would be 5200/6000w which is an overload already for 2 and 2.

 

[spuddle]

Do you have a load bank? Or something something you could use to load the gen set to rated load, besides the battery charging setup? If so, disconnect the battery charging set up. Hook something else up to the set and load the set to rated load. Will it run right?

Was redoing my solar system, and has the house running off the gen just fine all day yesterday, then when got everything hooked back up and started charging batteries is when i started running into it tripping the overload.

I say this, so that you can eliminate the possibility that something got hooked up wrong after the work on the solar system. Normally we would start telling you to clean the S8 switch with contact cleaner. That seems to be what helps out with most of the overload problems. But over the years I have found that when something worked before I did work on it, and didn't work later, I hooked up something wrong. Food for thought.

You are absolutely correct. Thank you for that reminder. And i am 100% not perfect. I wish i had tried this before redoing everything so i would have a baseline to go off of. Unfortunately i was assuming since it ran and ran off the convenience plug that it was all good and never fully tested it.

Not arguing by any means, but typically when hooking something improperly with solar/inverters they either go into error mode or let the magic smoke out. Doesnt mean that i didnt do something wrong tho.

As for running just the house, loads were maybe a max of 1500-2000w sustained. Thats on the high side with fridge, freezer, fans etc. the inverters are the old transformer type, so in the reactive loads rather than resistive i figured 5k x .8 = 4k. Thats why i was trying to cap it around 4k for charging/running the house.

I will see about making a home made load bank and testing tho. Thats a good way to eliminate my human error. Will also check out S8 for anything looking off and be prepared to clean it.

Was also thinking to hook up my other 802 in place of this one to see if it has the same issues, but i havent really gone through it either yet.

This was all for temporary use until i can get my primary 26kw diesel back wired into the system, but that will be about a week or two away at least.

 

[2Pbfeet]

Hey, idk why i have thought about that before. Thats actually a great idea. I do have some 1300/1500w milkhouse heaters. That would be exactly a load bank. Here i was thinking about something big and expensive. Thank you for bringing that up. I will have to give that a try.

I always try to load balance the generators tho, so question would be in 120/240 mode, that would be 2 heaters on one leg and 1 on the other for 4500 watts, thats a pretty big load imbalance. Is it going to be ok that way, or should i try to find something 240v to keep it balanced? Otherwise that would be 5200/6000w which is an overload already for 2 and 2.

Balancing the load is always a good idea in my view.

There is also changing the S8 voltage/phase switch to 120 only and putting all the heaters on 120. Some milk house heaters are 120/240 inside, so in my book, it never hurts to check to see what your options might be. For example, the 240V heater that I bought turned out to have control boards and terminal strips for 3 phase operation inside, though not labeled as such on the outside. In the end, I did not wire it up that way after some reflection.

All the best, 2PbFeet

 

[LuckeyD]

No shut down. Lets separate mechanical from electric issues first. Nothing connected to any load terminal or outlets. Cold. Start the thing and after it is running again normally, keep an eye on the fuel solenoid and turn the S1 to OFF. Does the fuel solenoid try at all to let go and push back to the off position? Yes, works great now; your load is sending a back feed. OR Yes, but it don't move enough; you are getting a fuel rack stuck. Causes- dirt, rust, injector pump not set correctly in rack, bent rack, fuel solenoid not connected correctly..... NO, It don't try at all, you have an electrical issue and need to see where the power is coming from. Use schematics from the TM section of the forum. This wiring issue can be causing both issues. Another possible issue is the A2 fault relay panel. Over load comes out pin 18 and will trip the K12 shutting you down. The S7 Battle short removes the K12 possibility of engagement.

Load banks: Try space heaters. on 120-240 the gen is set in a double DELTA and you are using the entire gen on L1 and L3 to L0. Try to find a dent and scratch at salvation army and play connect it up to load terminals. Take your K8 and remove it tagging wires and when you have it out go to a lit place and drill the rivets. Now carefully open and inspect the insides for any signs of heat or corrosion.

 

[spuddle]

Balancing the load is always a good idea in my view.

There is also changing the S8 voltage/phase switch to 120 only and putting all the heaters on 120. Some milk house heaters are 120/240 inside, so in my book, it never hurts to check to see what your options might be. For example, the 240V heater that I bought turned out to have control boards and terminal strips for 3 phase operation inside, though not labeled as such on the outside. In the end, I did not wire it up that way after some reflection.

All the best, 2PbFeet

Well glad we are on the same page with balancing. Dumb question now, is there a difference with the testing of the gen in 120 vs 120/240 mode? Like, would there be a separate issue that would only show up in 120/240 mode that wouldn't show up in 120? I believe i remember seeing something about testing the load banks in here about running it on 120/240 for testing the K8. But maybe i misinterpreted that. Maybe that was just so could run 240 load banks?

 

[spuddle]

No shut down. Lets separate mechanical from electric issues first. Nothing connected to any load terminal or outlets. Cold. Start the thing and after it is running again normally, keep an eye on the fuel solenoid and turn the S1 to OFF. Does the fuel solenoid try at all to let go and push back to the off position? Yes, works great now; your load is sending a back feed. OR Yes, but it don't move enough; you are getting a fuel rack stuck. Causes- dirt, rust, injector pump not set correctly in rack, bent rack, fuel solenoid not connected correctly..... NO, It don't try at all, you have an electrical issue and need to see where the power is coming from. Use schematics from the TM section of the forum. This wiring issue can be causing both issues. Another possible issue is the A2 fault relay panel. Over load comes out pin 18 and will trip the K12 shutting you down. The S7 Battle short removes the K12 possibility of engagement.

Load banks: Try space heaters. on 120-240 the gen is set in a double DELTA and you are using the entire gen on L1 and L3 to L0. Try to find a dent and scratch at salvation army and play connect it up to load terminals. Take your K8 and remove it tagging wires and when you have it out go to a lit place and drill the rivets. Now carefully open and inspect the insides for any signs of heat or corrosion.

Thank you. I was just coming back to update about the nit shutting down. And yes, completely unrelated to the overload issue. The fuel shut off solenoid was working as it should, but previous owner evidently removed the spacers between the slide and the pump lever. This was causing the slide to hit the pump and prevent shut down. Fixed! Nice when its easy sometimes..

I will be digging into the wiring/relays/contacts now. Thank you for the heads up on the A2 circuit. Will look into all of that. Guess its time to open the K8 and see whats going on as well. Seems to be a major problem with these things i keep reading about. And now an obsolete part that cant buy anymore to replace.

 

[kloppk]

Before tearing into K8 (it rarely goes bad) I'd suggest measuring the AC voltages going into K8 as detailed in the thread I suggested. Very likely you'll find one or more of them way to high causing K8 to trip the overload.

This post.. (updated below for your trip point)

I'd suggest doing the following to narrow down if it's a K8 problem or a burden resistor or S6 or S8 switch contact issue.
Running is 120/240 mode apply your load of slightly less than 2,500 watts.
Then measure the AC voltage across K8 terminal pairs:
1 & 4
2 & 4
3 & 4
Each pair should have about 2.8 volts AC. This would be the expected AC voltage on them with a 2,500 watt load.
If you have about 2.8 volts or a bit less at each pair AND the Overload trips then you have a bad K8.
If find one or more pairs with way more than 2.8 volts AC then there is a burden resistor, S6 and/or S8 contact issue in that path.

 

[LuckeyD]

The parts information for the Burdon resistors and the K8 were about the same. Units requested them about the same. This issue was not one you saw everyday. It usually showed up (when it did) after a wash rack trip or agricultural cleaning returning from a foreign land. As far as any differences when loaded only the suppression components behind the load terminals come into play. Please ensure the S8 is actually set into position before starting the gen.