Boom Truck Blues for Your Amusement

[CALCXX]

Yes

[CALCXX]

I'm curious. Mine produces 240v. Is your RV Gen-set tapped for 240 or 120V only?

I have no knowledge of RV's. I thought they are 120V only. Is that true?

Mine is on a homemade cart and has electric start. 

Edited April 25, 2021 by CALCXX

[CALCXX]

Oscar, may I suggest you put your voltmeter on the battery terminals while the Gen-set is running stand alone? I am curious why yours doesn't charge all night in the desert.

[superhawk996]

Is your cart generator a unit that was pulled from an RV?  Post a pic please.

 

Mine is 120v only.  I've never seen an RV that uses 240 nor an RV generator that was labeled as having 240.

 

I don't let it run all night in the desert, I run it as needed for doing stuff needing AC and occasionally just to recharge the battery.  Like all RV's, the rig has a battery charger that runs off the gen.  I won't run it disconnected from the battery out of fear that something could be damaged, but I might check for a charging output at some point just for shits.  From many RV experiences I know that if they do have a charging circuit it's a very small amperage that'll do nothing noticeable for an RV battery.

[CALCXX]

You are embarrassing me now. I would have to dig that fukr out from underneath the table saw behind boxes of treasures to take a picture for you. The thought of the generator running only until the battery dies is not what I would take camping. LOL

 

I'm glad you can occasionally just to recharge the battery.

fwiw, Joes name plate shows 120/240v. it must not have come from an RV ?

Edited April 25, 2021 by CALCXX

[rockmeupto125]

Thanks for everyone's continued thinktanking.

 

From this morning:

 

 

The four white wires come from the generator.  There's two closest to the cable clamp.  We'll call them D and C. Those two have continuity with each other, with a small amount of resistance.  Neither has continuity with wires A, B, or chassis ground.  Wire A has continuity with the chassis.  Wire B has continuity with the chassis, but with a small amount of resistance.  About the same amount of resistance as between wires C and D.  The small box with the yellow crimp ends is a circuit breaker, and those wires are cut, they just look connected because of the angle.

 

And then this:

 

That solenoid has 4 posts, mains on the L and R, and controls on the front L and R.

Voitage measured at the R main post is 9v.  The same voltage is measured at the L and R control connections.  

 

Battery voltage on the main is 12.3, on the auxiliary is 12.0.  When the fancy Battery Jumper switch is engaged, the voltage on those terminals rises to 12.3.    I have to find out where the missing 3 volts went to.

[superhawk996]

9 minutes ago, CALCXX said:

You are embarrassing me now. I would have to dig that fukr out from underneath the table saw behind boxes of treasures to take a picture for you. The thought of the generator running only until the battery dies is not what I would take camping. LOL

 

I'm glad you can occasionally just to recharge the battery.

EVERY RV HAS AN ON BOARD CHARGER THAT RUNS OFF THE GENERATOR.  I had to shout because it seems like you're not understanding that.  Any time the generator is running the rig's charger is charging the battery.  The generator isn't doing the charging, it is powering the rig's battery charger to do it.  When the rig is plugged into an outlet at a camp ground the same charger is running.  Most of the stuff in an RV is run off the battery so it needs to have a charger even if you're plugged in at a campground.

 

The only AC powered stuff installed in the rig is the air conditioner and microwave, everything else runs off the battery.  Typically we run it 2-3 times/day for a few minutes each time; make toast in the morning, possibly microwave something, and to run the cigarette machine.  That's not enough to fully recharge the battery, but enough to keep things working fine 'till it comes home.  Then it gets plugged into an outlet in the back yard and the on-board charger brings the battery back to 100% and keeps it there, ready for the next outing.

 

Are you sure your generator is an RV unit?  Not something that someone used for powering an RV at some time, but a generator actually made for installation in an RV.  I'm guessing not, but am very curious.

[CALCXX]

Oscar, no reason to shout. I never said my Onan 4.0 came from an RV. Your Onan says RV. Mine does not. Your Onan makes 120v. Mine will make 240v and Joes nameplate says it will also.  Thanks for the RV education but honestly, I don't give a damn. 

 

Joe, I lied. It seems I have been drinking all night. Talk to ya later.

[superhawk996]

15 minutes ago, rockmeupto125 said:

That solenoid has 4 posts, mains on the L and R, and controls on the front L and R.

Voitage measured at the R main post is 9v.  The same voltage is measured at the L and R control connections.  

 

Battery voltage on the main is 12.3, on the auxiliary is 12.0.  When the fancy Battery Jumper switch is engaged, the voltage on those terminals rises to 12.3.    I have to find out where the missing 3 volts went to.

Sounds like lots of monkey rigging went on.  The solenoid input should be connected straight to the auxiliary battery +.  My guess is that they wired it to the isolator input/engine alternator output, if I'm correct the generator won't crank without turning on the jumper switch.  It's also possible that it just has a shitty connection somewhere, but I don't know why flipping the switch would cure either of those problems unless the solenoid is connected to multiple battery + connections.

[superhawk996]

4 minutes ago, CALCXX said:

Oscar, no reason to shout. I never said my Onan 4.0 came from an RV.

I asked earlier if it was an RV unit and how you verified that it charges and you said something like "yea, I tested it in my shop."  I thought the "yea" was answering that it is an RV unit.  Before that I stated that if it's a portable electric start generator then it will have a charging circuit.  I'm not trying to make this a pissing match, just trying to eliminate confusions about generators.

[superhawk996]

32 minutes ago, rockmeupto125 said:

Voitage measured at the R main post is 9v.

Does it have a fat battery cable connected there or just multiple smaller wires?  If it has a fat cable you need to find where it's connected.  If it's on the battery post make sure it's got a good connection.

[rockmeupto125]

I just need to start isolating a bunch of stuff, starting with the isolator. PIA because of the distance, gotta use jumper cables to check everything. Do they make VOMs with bluetooth connections?

[rockmeupto125]

It's a power cable. That's where i used to hook up a jumper battery to start it. Headed to bed... 

[CALCXX]

Oscar, it does make 240v and it does charge the battery. Thanks for verifying that it is not an RV unit.

[CALCXX]

The starter relay with the small wires is more than likely the starter motor circuit for the generator and the starter relay with the large wires is probably the battery isolation tom foolery.

 

Good night boys. 

[rockmeupto125]

Crossed the white wires today.

 

The two that have continuity to chassis ground, when connected to my VOM, read 140 volts AC. 

 

Any connection with the A and B wires to C and D reads 10-14 volts AC.  Ermagerd.

[superhawk996]

I have a lot of guesses, but since the readings don't make sense to me and I'm not very knowledgeable with AC, and I'm too far to realistically inherit the machine after you get fried, I won't bother throwing out potentially deadly/wrong info.

 

My suggestion, if nobody comes along with an answer, is to actually label them A,B,C,D.  Probe every possible combination of them and post the readings.  Do the same with probing each wire against the generator chassis and van chassis.

[CALCXX]

I agree with Oscar. Wires need to be identified and labeled.

If you look at Fig 3-4 Section 3-7, The drawing shows 7 wires leaving G1. 

Four of them are the main focus here for now. The wires they have marked as

M4 - is neutral, M2- is ground, M3 - is a phase conductor, M1 - is also a phase conductor.

The ground should be easily identified by measuring resistance to the chassis. (should read zero)

The drawing shows the neutral and ground bonded at the terminal strip.  I doubt it's bonded inside the generator? Maybe so? Your ohm meter should prove this. The phase conductors are shown connected also. Then the drawing shows this terminal feeding cb1 with an optional cb2 with 120v only potential.

That does not match your nameplate yet it matches the RV way of use so I am also cautious to advise connection. Ac voltage needs to be measured between any combination of conductors. There should be wires elsewhere leaving G1 going to the starter relay (k1), a wire to grnd and a wire to a blocking diode. (K1 energizes a winding in the generator making it a temporary starter motor.) Not real concerned about that right now because you can start it. Later on we can check for dc voltage after the blocking diode.

 

I now realize after pissin out the martinis and beer that my Onan 4.0 is a contractors model and doesn't fit this conversation. I know absolutely zero about this battery isolation gizmo. So, I am probably not much help here.

 

 

 

 

 

[rockmeupto125]

Cal, the battery isolator ir not a part of the genset, it's an add on device to keep the battery that powers the Onan from discharging the main system, but allowing it to be in the system to be charged by the truck's alternator. It's a separate issue at this point.

 

One of the wires that are continuous with ground has both 2 and 4 stickers on it.

 

I'll try to plot these out today.

[SwampNut]

Humor me, see if there's DC where you got 140 AC.

 

[rockmeupto125]

Will do.  Right now I'm in the middle of a massive screwup on my part.

 

Yeah, I'll help you out and change your tires for you.

 

He didn't say his POS vulcan has TUBE tires.  😡

[CALCXX]

It could be worse. He could have rim locks.

[rockmeupto125]

I labelled the four white wires 1 through 4.

 

Not running, I tested continuity.

1 and 2 have continuity to chassis ground.  3 and 4 do not.

1 and 2 have continuity to each other.  3 and 4 have continuity to each other.  Any other combination does not have continuity.

 

Engine running, I tested for voltage.

1 and 2 make 145 VAC.  3 and 4 make 145 VAC.

1 and 3 make 10 VAC.  1 and 4 make .5 VAC

2 and 3 make .2-.4 VAC.  2 and 4 make 14 VAC.

 

I tested 1-3, 1-4, 2-3, and 2-4 for DC without any reading.  I did NOT test anything to ground while running, especially after the brilliant spark from either 3 or 4 , I think the alligator clip touched the casing.

 

Apparently the control panel depends on the engine running to energize it.  The emergency bypass to the lift valve (that opens the return line and allows the boom to lower) will only work with the engine running.

[superhawk996]

18 minutes ago, rockmeupto125 said:

Apparently the control panel depends on the engine running to energize it.  The emergency bypass to the lift valve (that opens the return line and allows the boom to lower) will only work with the engine running.

Very odd since the engine is making no electricity for the vehicle/boom to use.  Does the battery jumper switch have to be on for the engine to run?  If so, did you try the emergency bypass with that switch on?

 

If the panel is truly only operational with the engine running that means it's sharing power with the generator stuff, like the fuel pump & ignition, which seems totally wrong.  Or maybe that switch isn't activating the emergency bypass solenoid and instead is activating the normal down solenoid which might require hydraulic pressure.  Either way, it would be easy to swap the panel feed from the generator controlled circuit to a battery line so that the emergency down will work with a dead engine.

[XXitanium]

Bad regulator? Should it be 120V and 240V?

 

https://gentekpower.com/forums/viewtopic.php?t=133