air compressor stalling generator

[bitsnpieces1]

  I read about this in one of the posts here, but, I can't remember which one.  So, I'll give it a shot in this post.

   The post was taliking about how his generator would lug down and almost stall when his air compressor came on with pressure in the tank.  There is a way to completely eliminate that action.  The larger air compressors have a compression release on the compressor itself that holds the intake (I think it's the intake) valve open with discharge to the atmosphere while the rpm is coming up.  Once the rpm is almost at speed the hold-open releases and the compressor starts pumping air to the tank.  The idea is to relieve the strain of compressing air until momentum has built up and the starting load of the motor is over.  Then compression kicks in and everything takes off. 
  This kind of thing is used for compressors starting with 90psi or so still in the tank.  I don't remember for sure, but, I think it is an attachment that could be installed on any compressor.   

[europachris]

It's called a "Load Genie" unloader, if I recall.  Grainger.com has them.

My little 1/2 horse compressor has a single cylinder Speedaire pump, and the check valve on the tank allows the pressure on the pump side to bleed off after the pressure switch shuts it down, so it always starts under no load.

My Changfa powered 3.2kW generator starts it like it wasn't even there (capacitor start motor), but the generator totally goes tits up on the 3/4 horse well pump (2-wire split phase).

Older compressors usually had head unloaders (constant run controls) and instead of shutting off the motor, they opened the intake valves and unloaded the pump.  My father has a 1 hp Binks compressor from the 60's that runs like that.  Great compressor.

I'm not sure what compressors today (most of which are that cheap, direct drive, noisy as he!! junk) unload the pressure side of the pump after shutoff, but that could be an issue for a generator.

Chris

[dkwflight]

Hi

This type of unloader is supplied on engine driven compressors. so they can start and they also regulate the pressure so the engine can run when the tank pressure is up to the limit.

 but the generator totally goes tits up on the 3/4 horse well pump (2-wire split phase). I have heard a "Hrd start kit" can help  water pumps. Check George Bs cd


Dennis

[bitsnpieces1]

    That's the thing.  I remember them being on start-up under pressure type and for ones that continue to run because of high air usage.  AND it's a simple pug-in.  Thasnks guys,  Les.

[europachris]

Hi
 
 I have heard a "Hrd start kit" can help  water pumps. Check George Bs cd


Dennis

I wish I could use one of those.  Unfortunately, they only work on "3-wire" well pumps that have a separate starting control.  Mine is a "2-wire" pump, which is basically a split phase motor.  It eats over 40 amps at startup (running is 6.5 @ 240V).  It just kills the generator with the surge current.

Chris