need electric schematic for M1084 A0

[Goodpedro]

Found the schematics for the 1084 A1 but zero for the A0. Can someone help

 

[Suprman]

Alot of the first gen tm schematics will apply to a 3126 truck. What are you trying to troubleshoot?

 

[wheelspinner]

Give me an email address. I have the schematics culled out from the complete TM

 

[Goodpedro]

pierre_trudeau2004@yahoo.ca

turning lights don t work...all breakers are ok but there is an electrical problem. Also something is draining my batteries real fast. Alternator lights are flashing so that is not the problem

 

[SausageGuy]

I am surprised you found A1 scematics because I thought those were in electronic format only and lots of people have been looking for them.
The ones in the TMs that are online are usually the A0.

 

[Ronmar]

I am surprised you found A1 scematics because I thought those were in electronic format only and lots of people have been looking for them.
The ones in the TMs that are online are usually the A0.

There is one A1 schematic here on SS in the manuals section under present conflict vehicles, end of page 1 or start of page 2 near the 1078 A0 manuals…

 

[Suprman]

If your crane control box switch is left on it will kill the batts fast.

 

[Goodpedro]

Suprman, do you mean the PTO switch on the dash?

 

[Suprman]

No on the crane is a control box left side it has an on off switch. If you leave that switch on it will drain your batts.

 

[wheelspinner]

No on the crane is a control box left side it has an on off switch. If you leave that switch on it will drain your batts.

this....is something learned the hard way.....

 

[Goodpedro]

alternator problem. Shit

 

[Ronmar]

alternator problem. Shit

A few things to rule out as the alt doesn’t output until it gets turned on by K11, which de-energizes when the engine sees 15psi of oil pressure. Since it uses the de-energized contacts of K11(pin30-47A), K11 must be a 5 pin relay. The relay shifts power down thru Kll to the forward terminal on the voltage reg. If you have a bad connection K11 might not be passing enough power down to the regulator to bring it on line. So I would look for battery 24V on the forward terminal on the voltage reg. If it is not there, you can put it there using a small jumper wire from the alt 24V output terminal to the regulator. This should bring the alt online then you need to find out what is wrong with the excitation circuit.

 

[coachgeo]

On the A0 the excitation circuit was a common failure point as they aged. Lot of mentions of this in here.

 

[Third From Texas]

Good time to slap a 200-300amp 24v alt on there. And then a step down for the 12v.

Be a crap-ton cheaper than a used surplus 12/24v dual voltage.

Assuming that the alt is the issue.

There are tons of HD high-output alts at there in the civilian/commercial world.

Here are some ideas on what to look for:

C.E. Niehoff Co. - Brushless Alternators - Commercial - Military - Mining - Construction

Generic Description Here

www.ceniehoff.com

 

[Third From Texas]

Example:
"Refurbished" LMTV dual voltage alt on BEay = $2000

New N1307 = $300
Step down= $10

 

[Ronmar]

Example:
"Refurbished" LMTV dual voltage alt on BEay = $2000

New N1307 = $300
Step down= $10

$10 stepdown? Please share, or was this a typo? I was figuring $100-200 for a bussman 100A converter to provide 12V. Still an order of magnitude cheaper than most all of the surplus dual volts available, and a straight 24V battery bank will last a good long time without fudzing with the 12v in the middle…

 

[Third From Texas]

I was thinking a simple 24v to 12v step down would do the job.

I guess price would be determined by how many amps you needed for that run.

Amazon.com

They appear to be about $10 for every 10amps.

 

[Ronmar]

I was thinking a simple 24v to 12v step down would do the job.

I guess price would be determined by how many amps you needed for that run.

Amazon.com

They appear to be about $10 for every 10amps.

It will if you pay attention to some details:

The main control relay that provides 24V switched/ignition power, is actually energized by 12V. So whatever power converter is used, you want to have a low cutoff voltage, otherwise it may shutoff the main relay when you try to crank. These switching power supplies typically can run the supply as low as 25-30% above the output voltage but you need to see the specs to insure that. Have had a bad connection limit loaded voltage so the truck just sat there and went click click click when the start button was pressed. I imagine it might do something similar if the supply to the converter dropped below the cutoff voltage during a crank. I have thought about shifting that instrunment relay control power to 24V and using a 24v relay…

The lighting load on a M1079 is as high as 33A, 26A on a 1078, the total load is a little north of those 2 figures respectively, plus whatever 12v accessories you choose to add. So you need one big enough to meet the total 12V load by enough to keep at a reasonable sustained load level.

Once you go north of about 40A the costs start to close on and surpass $100 you could split the 12V buss up and use smaller power supplies to power different legs… you can get sealed/potted water resistant heat-synced 25A versions for $29…

Amazon.com: DC Converter 24V to 12V Step Down Converter 20A 240W Power Supply Converter with Fuse Waterproof, Voltage Reducer for Golf Cart LED Motor Truck Vehicle Boat Solar System (Accept DC 15-40V Inputs) : Electronics

Amazon.com: DC Converter 24V to 12V Step Down Converter 20A 240W Power Supply Converter with Fuse Waterproof, Voltage Reducer for Golf Cart LED Motor Truck Vehicle Boat Solar System (Accept DC 15-40V Inputs) : Electronics

www.amazon.com

Typically when they say 12v output, they mean exactly 12.0 VDC. 12.0V is a little on the low side of a typical 12v automotive system At 14-15V when running. Everything will work, but it will just pull a little more current, so something to be aware of. A unit with an adjustable output would be my preferred…

Like an unloaded inverter will put a load on their source even when no load is connected to them, so you would need to disconnect these units completely When not in use. You could use a large relay to control the input to the converter so it shuts off when the main switch is secured. 50A @ 12V = 25A at 24V plus efficiency losses, so not even a really serious relay To do this.

The Bussman gets around a few of these as it doesn’t output 12, it outputs 1/2 of the input, so doesn’t have the input cutoff limit issue, as input goes down say while cranking, so does the output, just like it would with batteries. It is also 100A, so it won’t be operating at max output. but I believe it may still vampire power without a disconnect in there somewhere…

nothing terribly difficult and still WAY cheaper than a replacement dual volt in most cases…

 

[Ronmar]

Victron makes a 70A unit with adjustable output and a remote on/off feature for about $140 so you would not need a relay in the main circuit. It’s cutoff voltage is 18V which might start to tickle the limits during a cold engine crank, but if the main power circuit was shifted to 24V it would not really be an issue while starting and the radio lockout relay could be used to control this supply and keep it offline while the engine was cranking…

Amazon.com: Victron Energy Orion IP20 24/12-Volt 70 amp DC-DC Converter Non-Isolated, High Power : Electronics

Buy Victron Energy Orion IP20 24/12-Volt 70 amp DC-DC Converter Non-Isolated, High Power: Power Converters - Amazon.com ✓ FREE DELIVERY possible on eligible purchases

www.amazon.com

 

[coachgeo]

Example:
"Refurbished" LMTV dual voltage alt on BEay = $2000

New N1307 = $300
Step down= $10

would the ears etc. of the N1307 even come close to fitting 3116 mount?

and the regulator has a vehicle harness... assume that is why you need schematic... what in harness is the excite wire? what else may snag using this alt hidden in that harness?