Wiring HOA Switch

[brianpgriset]

Quincy QT compressor. Ordered the proper HOA switch kit per the label inside the starter. I think I know what to do but want to check.

FYI I get continuity between yellow and black wires off the back of the HOA switch with "Auto" pushed and continuity between yellow and red with "Hand" pushed.

Remove "downstream" wire from pressure switch (currently at A1) and wire this to black wire. Land yellow wire on terminal A1. Land red wire on L1 (line voltage).

My understanding is this will put the pressure switch in front of the "Auto" push button, and will provide power to coil through yellow wire. With "Hand" depressed, this will bypass the pressure switch and jumper power directly from L1 to A1 which will in turn power the coil and run regardless of pressure switch.

Does this sound right? Also, this won't effect my overload protection right?

 

[Norcal]

Why would you need a HOA switch on a air compressor? A common use for those is agricultural pumps where "hand" would manually start the pump, & "auto" would be a timer to run it in off peak times to take advantage of lower off peak power rates offered by the PoCo. The last thing you want w/ a air compressor is to run it in a manual setting as the pressure switch takes care of demand & if one wants to shut it off, a simple selector switch would take care of that.

 

[brianpgriset]

Why would you need a HOA switch on a air compressor? A common use for those is agricultural pumps where "hand" would manually start the pump, & "auto" would be a timer to run it in off peak times to take advantage of lower off peak power rates offered by the PoCo. The last thing you want w/ a air compressor is to run it in a manual setting as the pressure switch takes care of demand & if one wants to shut it off, a simple selector switch would take care of that.

Don't worry about that, I want one.

 

[Aceman]

I agree with Norcal.

A 2 position on/off switch would be more appropriate than a 3 position HOA switch. I must not understand why you'd need to override the pressure switch with a "hand" function?

 

[Norcal]

I rewired a combination starter that was a old pump panel for my compressor, was the only single phase combo starter that I had ever seen, it had a HOA selector switch which I wired shut it down & used the pushbutton for a solenoid valve on the tank drain.

For those who don't know, a combination starter, is a combined disconnect, which can be either a fusible, or non fusible switch, or a circuit breaker, & the motor starter in one package/enclosure.

Wiring that HOA cover control kit for just the "auto" position may work, the cat # is a C400GK2?

 

[brianpgriset]

I rewired a combination starter that was a old pump panel for my compressor, was the only single phase combo starter that I had ever seen, it had a HOA selector switch which I wired shut it down & used the pushbutton for a solenoid valve on the tank drain.

For those who don't know, a combination starter, is a combined disconnect, which can be either a fusible, or non fusible switch, or a circuit breaker, & the motor starter in one package/enclosure.

Wiring that HOA cover control kit for just the "auto" position may work, the cat # is a C400GK2?

It's the GK3 kit. I specifically wanted an HOA so i have a simple push button continuous run which is common on large compressors, plus the GK3 kit was only a few dollars more.

I'm primarily worried about the terminations as the provided instructions were only for a stater, not a starter plus pressure switch plus overload.

 

[LS6 Tommy]

You might want to check the duty cycle of your motor and compressor. They may not be real happy with continuous run duty...

Tommy

 

[Norcal]

You CANNOT have continuous run w/ a normal compressor!!! They have to be plumbed to operate that way, what will happen is the safety valve will go off if you bypass the pressure switch.

 

[brianpgriset]

So is anyone going to answer my question?

 

[C96]

So is anyone going to answer my question?

Yes, I will answer as much as I hate to because this is just plain wrong. You are correct with the way you plan to wire the HOA if you want the compressor to run indefinitely while in the Hand position.

I specifically wanted an HOA so i have a simple push button continuous run which is common on large compressors

WTF are you thinking….LOL. This makes no sense.

I'm primarily worried about the terminations as the provided instructions were only for a stater, not a starter plus pressure switch

Gee…..I wonder why

Please clue us in on why you must have this option.

 

[CoopVA]

^^^ Yep, what he said...

 

[brianpgriset]

The manual for the QT and QTS compressors shows a plumbing diagram for dual control allowing a continuous run feature. I wanted to be able to do this for sandblasting large parts so the compressor doesn't cycle so often. If in future I wanted to do this, I can do so with a push button instead of venting at the pressure switch.

Also, I could use this to test the relief valves as well.

The added cost of the HOA vs. the start stop switch was a few dollars more and it made sense to me to get a pilot override for the case I need it in the future for a few dollars more now.

Based on everyone's strong reactions to this I'll just leave the hand function unwired so it essentially becomes a start/stop switch.

Thanks.

 

[sberry]

Brian,,, the reason everyone wonders "why" is valid here. Real smart people can complicate a lot of things, multiply it with fears about the future and soon the system design spins off from standard,,,, millions of them, with carefully designed safety features, its so easy to overlook some stuff. I was copying some stuff and finally had to look at UL listed, took a long time to reverse engineer and still had to make some accommodations to a makeshift design I am not all happy about.

Its different than back tailoring a system as it evolves, there is enough stuff down stream for a new user to fiddle with to get going, a little pipe, a regulator and some hose vs re working a carefully engineered design with added equipment not called for in code.

 

[EOC_Jason]

The continue run feature requires a little extra hardware. While the motor will run continuous and the pump will constantly run, there is an unloader valve setup so the air going through the pump is not under pressure.

Google "continuous run unloader" if that is your goal...

 

[W-Cummins]

You do not need the hand setting for the unloaded operation either! Just set it to unload just under the cut off pressure of the pressure switch. Then it will run like you want, with out the problems of locking out the pressure switch ie. OVER PRESSURE!!!

So if you want to operate in unloaded mode get the unloader control valve that has the toggle on it so you can turn it on and off.

I run my compressor in unloaded mode all the time and it's great for blasting. It is set for 144-155 psi with the pressure switch set at 165, close the pilot valve and it will pump up and switch off until I need it to run unloaded again.

William....

 

[Milton Shaw]

My first air compressor I put together has a compressor off a tractor trailer. The head of the compressor had unloader valves in it so that when pressure was reached the valves opened and air just blew back and forth between the two pistons. I have not seen that on home type air compressors but have seen similar on constant run portable compressors. A pop off valve is not the same thing as it doesn't stop the compressor from pumping but blows off at set pressure say 125psi etc. I would not mess with controls on compressor to make it constant running in case you didn't watch it carefully enough.