003a breaker trips when loaded

[rickf]

Thats why you get a folding chair and put it 3-4 feet away from the box. I have had some real exciting moments in my life. Light shows. So I too have a real aversion to light shows.

Electrical arcs and incoming tracers, Both are light shows and both will have the same effect on your body. Been in the presence of both and have thankfully avoided them.

 

[Guyfang]

Once I was changing a Circuit Breaker in a transformer building for a small town. The short version is that the 19 mm socket somehow came of the ratchet extension I was using. I was DONE. Just trying to withdraw my tools and self from a place I did not really want to be. The socket fell off, and bounced twice. I can distinctly remember seeing it bounce. The was the last thing I remember seeing, for a while. The socket made its home between L2 and L3 buss bars. Popped both 480 Amp fuses and turned daylight into a super nova. I was blind for 30-45 min. As my sight began to start to come back, everyone who had this great idea to this work without shutting down the town, had urgent things to accomplish someplace far away. I was killing mad.

 

[DieselDr]

OK guys ,finally got time to work on this again ,this afternoon.
Where is the best place to check the inrush to the ac breaker?

 

[DieselDr]

Checking at L1 38A
L3 36A.
Now what?

 

[DieselDr]

@DieselDr Thanks for the clear photos; in the series of photos that you posted, #3, the one that @Guyfang reproduced, it seemed as if the wire bundle below the switch had some brownish residue or discoloration both between the wires in one place and also where the cable ties seem to cross. Is that real, or just dirt?
View attachment 926010


In your second photo, there is a bit of wire that looks like it ends in a frayed bit of insulation. Is there an unseen connection there (red arrow)?
View attachment 926011

All the best,

2Pbfeet

The discoloration looks like rust but I don't know where it came from. Same on the cable tie.

 

[DieselDr]

Checking at L1 38A
L3 36A.
Now what?View attachment 926872

OK guys, what is my next step? I tried one of my welders and it will run the cooling fan in it but I didn't try welding anything. In testing the inrush current on each leg of the output conductors, I used the 5hp air compressor motor as the load. I got 36A on one and 38A on the other leg. Is this too much for the output switch/breaker??

 

[DieselDr]

I hope everyone is doing well.

 

[rickf]

I see another circuit attached to the lugs, is that an active circuit and has it been checked for shorts? And you say you used the compressor motor, was it hooked up toe the compressor or just the motor alone? Last question is with the compressor, is the head unloader working so you are not starting against tank pressure? I don't see where those amperages should pop the breaker. Average of 37 amps at 240 volts is 8800 watts. It is getting close but I don't think so. Some id=f the others more familiar with these sets will hopefully chime in.

 

[DieselDr]

I see another circuit attached to the lugs, is that an active circuit and has it been checked for shorts? And you say you used the compressor motor, was it hooked up toe the compressor or just the motor alone? Last question is with the compressor, is the head unloader working so you are not starting against tank pressure? I don't see where those amperages should pop the breaker. Average of 37 amps at 240 volts is 8800 watts. It is getting close but I don't think so. Some id=f the others more familiar with these sets will hopefully chime in.

The other line attached to the lugs is the extension cord that goes in the garage to power the compressor. The big cable that goes into the gray conduit is the line going to the house. These cables work perfectly when the house panel is supplying power to the compressor. The lugs are just a connection point when not using the generator.
The compressor is run on a 50A breaker from the house panel without any problem. The unloader in the compressor works as designed.

 

[rickf]

So if you are supplying the house with the generator and you run the compressor you have no issues? If that is the case then the problem is in the wiring you are using that does blow the breaker. What size and how long is the run?
If you can run the compressor from the generator through the house there has got to be a problem with the only variant, that is the wiring from set to garage. A loose connection will drive up amperage a lot, not to mention it can start a fire. That is the last thing I can think of, need some of the electrical wizards to jump in.

 

[DieselDr]

So if you are supplying the house with the generator and you run the compressor you have no issues? If that is the case then the problem is in the wiring you are using that does blow the breaker. What size and how long is the run?
If you can run the compressor from the generator through the house there has got to be a problem with the only variant, that is the wiring from set to garage. A loose connection will drive up amperage a lot, not to mention it can start a fire. That is the last thing I can think of, need some of the electrical wizards to jump in.

Here's how it's wired. The lugs on the generator are a connection point for the cable from the house and the 'extension cord' that goes into the garage to provide 220v power for whatever I plug into it. The end of the cable at the house is connected to the fuse panel at a 50A breaker.
In normal usage, the house provides a 50A line to the garage. Everything I can plug into the cord, works just fine.
If the power is out, you switch off the panel MAIN breaker, fire up the generator to backfeed the house through that 50A breaker and the garage too,of course. I never have gotten to use the generator to do this yet.
Now I am working on getting the generator to supply power to JUST the garage, as a test, before trying to feed the house.
Clear as mud to everyone? Think of it as the generator is T'd into the line from the house to the garage. It does nothing during normal operation of the power from the house.
The problem I'm having is(with the 50A panel breaker off ,not feeding anything in the house) the output breaker on the generator tripping as soon as a load is put on it. A 5hp motor turning a couple of v-belts and a flywheel (not the air compressor) is not much of a load.
If I get time this weekend I will measure the amp draw of my compressor and the power hammer motor, running on power from the house. This will give the experts on here an idea of what the loads are I'm trying to run.
The problem is in the generator and I need help sorting it out.

 

[Scoobyshep]

You are setting yourself up for a massive injury to yourself or others. To properly feed your house you need at minimum an interlock to prevent generator current from ever leaving your home. Using the generator lugs as a feed through to power your air compressor is a big nono.




Sent from my SM-S908U using Tapatalk

 

[DieselDr]

You are setting yourself up for a massive injury to yourself or others. To properly feed your house you need at minimum an interlock to prevent generator current from ever leaving your home. Using the generator lugs as a feed through to power your air compressor is a big nono.




Sent from my SM-S908U using Tapatalk

OK, using the generator lugs as a connection point for a 50A breaker protected circuit, with the generator breaker off and generator not running is bad how?
Please explain. Is there going to be anything energized in the generator that will damage anything in it, when the circuit from the house is on?
Crazy that it has worked flawlessly for the last 11 years.
I assumed the lugs are inactive to the generator with the output breaker in the off position.
I will handle the situation with the generator feeding the house AFTER I GET THE GENERATOR TO EVEN FUNCTION CORRECTLY.
Thanks for any info.

 

[Scoobyshep]

There is nothing preventing you from :
A. Turning on the generator with line power available
B. Turning the generator on during an outage with the house main in the closed position.

The only thing preventing the generator current from reaching outside of your home is a written procedure of what to turn on and off. There so no physical means of interlocking power feeds. It is a pretty big NEC violation and it's the way linemen get injured or even killed. In my 25+ years in the trade I know of at least 3 brothers that didn't go home because of this exact practice.

 

[rickf]

To add to what Scooby is saying, The same transformer that drops the voltage from 6,000 to to 240 for your house will also raise the 240 from a generator to 6,000 on that line. Granted linemen will check the line to see if it is live but what if that genset comes online while they are working on that DEAD line after verifying it is in fact dead? Better safe than sorry. I have a lockout panel that will physically not allow me to engage the input breaker from the genset until I have opened the breaker for the main. They are quite economical.

 

[DieselDr]

There is nothing preventing you from :
A. Turning on the generator with line power available
B. Turning the generator on during an outage with the house main in the closed position.

The only thing preventing the generator current from reaching outside of your home is a written procedure of what to turn on and off. There so no physical means of interlocking power feeds. It is a pretty big NEC violation and it's the way linemen get injured or even killed. In my 25+ years in the trade I know of at least 3 brothers that didn't go home because of this exact practice.

I completely understand that and I am sorry for your loss.
NO ONE and I mean NO ONE ,is going to be operating this system but me. 40+ years of working on all kinds of things, and wanting to know everything about them is how I have learned so many things. My oldest daughter recently has said I have a kind of a, OCD type thing, that when I want to fix/work on something, I want to know as much as I can about it and retain it. Which is not really a bad thing.
Kind of a Renaissance man of today.
Never stop learning.

 

[glcaines]

Transfer switches aren't that expensive, especially if you consider the potential downside for not having one. I found a brand new 400 Amp Square D manual transfer switch on Ebay for use with my MEP003A for a couple hundred dollars. There is only one way to do things and that is the correct way. I routinely run my welders, and two 5 HP compressors with my MEP003A. No problems. I can also run my entire house with two ovens, dryer, geothermal heat pump and most lights on at the same time and the breaker has never tripped. The engine will lug down significantly when the large load is applied, but the breaker has never tripped. After correcting your wiring issues and switch problems, I would disconnect all wiring from the lugs and start testing with small loads connected directly to the generator and then increasing the load up until you have data supporting what loads you can accommodate. A load tester would make it much easier. You can construct a load tester yourself using dryer heater coils or try to rent or borrow one.

 

[2Pbfeet]

I completely understand that and I am sorry for your loss.
NO ONE and I mean NO ONE ,is going to be operating this system but me. 40+ years of working on all kinds of things, and wanting to know everything about them is how I have learned so many things. My oldest daughter recently has said I have a kind of a, OCD type thing, that when I want to fix/work on something, I want to know as much as I can about it and retain it. Which is not really a bad thing.
Kind of a Renaissance man of today.
Never stop learning.

That all may be the case, but the electrical setup that you described isn't intrinsically safe for something that is potentially lethal. A generator interlock or transfer switch will keep folks safer, including you.

 

[Guyfang]

Have you ever hooked a DMM to the output load terminals with the gen set off and circuit breaker off? If there is a cable from your hose hooked to the output terminals, (and the terminals are nothing more then a buss bar for all intents and purposes) then there is always a possibility that these terminals are hot. For example, when you parallel two gen sets and turn one off. If you do not have a circuit breaker in between, then the load terminals on the turned off gen set are hot.

 

[rickf]

And we ALL make mistakes! I have been a master mechanic for 55 years and just today I made a mistake putting a carburetor back together. We get complacent and we think we have everything under our control. I owned a shop that specialized in carburetors and automotive electrical, I have rebuilt hundreds upon hundreds of carburetors. And yet, I screwed up on one today, thankfully my own.
This statement right here, "40+ years of working on all kinds of things, and wanting to know everything about them is how I have learned so many things. " , shows you have not learned all you need to know. Otherwise you would know to use a mechanical lockout of some sort. We are always learning so here is todays lesson, the power setup. I am not going to keep harping on this since you have heard it from several of us and there is no need to make enemies over this.
But just keep in mind that no matter how much you know it is never foolproof. It is never everything.