Compressor and electrics question for those that know??

[Bloodyaussie]

I have a 1HP compressor and wanted to run it off an inverter.

Now here is the problem, it is a 2500watt with 5000peak inverter and the compressor is a 1HP with an 8lt tank now when the battery isolator switches over between batteries the inverter does not cope??

It makes a loud beeping sound and the compressor stops.

When it is running off the battery while the engine is on it works perfect until you hear the isolator click over to the other battery then it fails??

Ideas or help would be great, if this fails I will take the tank off and run it with my TJM compressor.

[Big_Roy]

Hey mate, I am no expert but it sounds like your 2nd battery might be on its way out. The reason I say this is most inverters have a low volt cut off which is the beeping sound you hear when the isolator switches over to the 2nd battery and stops supplying power to the compressor.
I would be checking your 2nd battery with a multimeter and see what it reads. A 1hp motor is equivalant to 750w so even when it kicks in your inverter should have more then enough power to run it.
Hope this helps, any experts out there please correct me if I am wrong.
Cheers.

[MudRunnerTD]

That Is a pretty big load mate.

Yendor will be your man I reckon,

You could may e run a link wire between the two batteries with an isolator switch to hot wire and bypass the Dual battery setup and use them in a parallel bank. Keep the engine running but I'd be probably be rethinking the air setup

[Bloodyaussie]

I ran it on both batteries and also 2 top batteries I have in the garage that are new.

The ones in the garage barely ran it.

It was only when the car was running no matter which way I hooked them up as soon as the isolator flicked over it stalled?????

[Yendor]

So the inverter is connected to the main battery? and when the battery isolator links the two batteries the inverter cuts out?

I would say the poor old GQ alternator is overload and just can't handle the load of running the vehicle, charging two batteries and running the inverter.

[Bloodyaussie]

Arr, now that makes sense.
What amp alternator do GQ's have and is there a larger one??

Think I will just rip the tank off this thing and hook it up to my TJM compressor?????

Thanks Yendor

[MudRunnerTD]

The standard GQ alternator on a TD42 is 60amps I think and yes you can get a bigger one. I run a120amp sucker and it is awesome

[Robo]

According to maverick - gq manual,
TD 90 amp alt.
TB 70amp, with a option 90 amp alt.
A compressor will want a lot of power on start up, so your system needs to be in good shape with a decent reserve power supply for a thirsty 240v item like a compressor.
what size batteries do you have now?

[MudRunnerTD]

According to maverick - gq manual,
TD 90 amp alt.
TB 70amp, with a option 90 amp alt.
A compressor will want a lot of power on start up, so your system needs to be in good shape with a decent reserve power supply for a thirsty 240v item like a compressor.
what size batteries do you have now?

Hi Robo,

mate i dont think your manual is right? Definitely NOT a 90amp alternator in a GQ TD42. If you search eBay you will find that most replacement Alternators for a TD42 are rated at 70amps Aftermarket and the odd one that is only 60amps. Are you quoting a Haymes or something?

The Factory Manual that i have here indicate that the Diesel range run a 60amp Alternator!

Current output: Amps/rpm
More than
26/1300
More than
42/2,500
More than
58/5,000

Based on the above your going to ring the neck of your poor old TD42 to even see max output from the factory Alternator! No wonder i used to run out of battery on every night run i did.

You can buy a couple of upgrades aftermarket. Patrol-a-part carry a 90amp and a 120amp with the Vac Pump bolted to the back. I now run a 120amp unit and rate it highly. The old Alternator would charge at 12.6v, the new one constantly sees 14.2v! My batteries are much happier.

[Bloodyaussie]

I just pulled an Alternator out of my spare/parts GQ and it appears to be a replacement and has larger plates but the sticker is gone and I dont know the total Amps???

Is there anyway of knowing??

[Yendor]

I expect your alternator is either 60 or 70 amps. Does the alternator that's fitted to your vehicle still have the sticker?

Are there any numbers on your second alternator?

[Bloodyaussie]

No stickers or numbers, the Alternator I pulled out of the spare looks nothing like the stock alternator and seems to have more plates so was thinking it was a larger one??

I might pop past an auto elect and get them to test it.

Seen some more GQ's with this set up and I like it and would like to make it work.

[MC97GQ]

Not sure if this would help, but don't the bigger alternators have the oil feed lines.

My GQ has an alternator with no oil lines connected so I am assuming it is the little one, but my mates GQ's alternator has the oil lines running to it so I assume it is the bigger one.

Mark

[MC97GQ]

Not sure if this would help, but don't the bigger alternators have the oil feed lines.

My GQ has an alternator with no oil lines connected so I am assuming it is the little one, but my mates GQ's alternator has the oil lines running to it so I assume it is the bigger one.

Mark

Scratch the above post did some research and answered my own question, it seems it doesn't matter if they have the oil lines or not as to what size the alternator is.

You should never assume, it makes an ass of u and me.

Mark

[Yendor]

With the old Bosch and Lucas alternators you could tell by the size of the stator (middle part of the alternator, between the two housing) the larger the stator the higher the output.

Not sure about the Hitachi alternators. Best thing is to get it run up on a bench test that way we will know for sure.

I reckon we are going to need at least 100 amps to make this work, even then we will need to go through and check the charge circuit to both batteries for voltage drop and possible rewire the main charge circuit.

As well as check for voltage drop to the inverter.

What engine do you have? I believe that an EL Falcon alternator will fit a TB42 without to much mucking around, from memory they are 110 amps.

[MudRunnerTD]

at the end of the day you are probably going to spend some Coin getting it to work! i'd be rethinking the Compressor your trying to run mate. Why do you need the 1hp 240v compressor and 18lt tank?

When pumping up tyres you want to bypass the 18lt tank anyway as it is just a bigger void to fill to tyre pressure and make a 35" tyre more like a 38" tyre to inflate ;) (= time lost)

If you need the 18lts to run a tool then any compressor will pump up your vessel to 120psi and then give you enough to do allot of things. Most things. At the end of the day the bigger alternator is a winner no doubt for all things on your car (winch, lights compressor, etc.) But unless your setting up your Work Truck as a Mobile Workshop then its just not required and false economics. If your setting up a workshop then whack in a triple battery system and a Big Alternator and a 240v bypass circuit for all options.

Just my thoughts.

[Robo]

Quoting a Gen Ford DA Maverick Manual, spec chart table.
I've gone back taken another look and !.
TD42 Model LR190-501c option for the "USSR" only, no other listing in spec chart table for TD.
No idea why we would need to know that here, but it was in there to throw us of go figure.
But re-looking at schematic on other pages of alts TD42 should be either---
LR160-437 or LR160-437E , both 60 amps.
hope that clears it up some , sorry for bad info.
cheers

[Bloodyaussie]

Well today I got round to seeing what I had under my bonnet and it turns out I already have a 120amp alternator ????

Going to have a word with the husband of the lady who looks after my son as he is a retired auto electrician..

I want to have an inverter on board for many reasons and would like to get this set up to work, we will see.

Cheers for all the help so far!!!!!!

[Yendor]

That's a bonus. Are you sure your second battery is in good condition?

[Bloodyaussie]

That's a bonus. Are you sure your second battery is in good condition?
Well I was up the high country in the snow for 3 days and had fridge/lights and so on and it did not miss a beat, either battery could not be faulted??????

Ron (auto elect) reckons it can be done but I should look to run the 12v compressor and keep the inverter for running the kettle/drill what ever.

He said the 240v compressor would be sitting at about 100amps but as the piston comes over top dead center it spikes to much higher and I could get a much higher alternator but not worth the dollars.

So I am going to rebuild my draws and fridge slide with this compressor setup all tucked away including the inverter.....

Thanks

[Robo]

ask your elec mate if a smaller pulley would help.
but you are already running 120amp alt so maybe a battery checkup and or larger capacity bats could be a solution/upgrade.