Vertical 80 gal air compressor

Easy!

A few steps.

Get a magnetic starter and a small relay with a 120 vac coil, a small powee cord, outlet with hardware needed and a panel mount or standard toggle switch.

First install the mag starter to control the motor and use the existing pressure switch to control the mag starter.

Make sure it is working properly.

The mag starter carries the heavy current and the pressure switch now only controls the coil in the mag starter.

Next in the mag starter or other place in the compressor mount the switch

A couple options here, simple on/off or local/remote or local/off/remote

On/OFF SPSP switch

Local remote is 2P2P switch

Local/off/remote is 2P2P switch but off in the middle.

On is RUN mode.

Local is you turn on or in run mode and pressure control controls motor just like you started.

Off is obvious

Remote is remote control.

Wiring simple.

We will do the easy one first.

The control wire between the pressure switch and mag starter is cut.

These wires are connected to the terminals of simple toggle switch so controlling the connection between pressure switch and mag starter you can control the compressor like a main power switch.

Now fun part.

Instead of connecting the cut wires to switch you mount the relay inside the man starter enclosure.

Connect the wires to relay contacts C and NO.

Attach a power cord like old pc power cord to the enclosure and connect the line wires as follows.

One side to relay coil a side and other wire to toggle switch not common connection, most have center that is common that switches to outside terminals, connect power wire to outside terminal, does not matter which.

Connect center terminal of switch in same row to relay coil b

For the local side you use the other side of the switch.

Splice into the wires connected to the relay between the mag starter and pressure switch and connect one to the center terminal on other row of terminals on the switch and the other wire to the terminal in same row but opposite end as the other wire.

When switch is one way it connects the power cord to the relay coil and it energizes connecting the pressure switch to mag starter.

When switched the other way the relay is bypassed and the above items are connected.

Mount the outlet near the air compressor and wire it to one of the shop lights so whenever the nights are on the outlet is hot.

It is highly suggested that next to the light switch you add another one in series with the outlet so you do not need to go outside to turn it off.

Now you plug the cord from relay into above outlet and compressor will be in run mode whenever the lights are on.

Having extra switch allows one to turn off so starting compressor does not startle folks.

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Additional notes...

If one uses a 3 way light switch added by the regular light switch they could wire it so the outlet is either controlled by light switch or on always

Second part is shop supply air.

We located an solenoid air valve with 120 vac coil on Amazon and it plugs into same outlet.

Turn out lights and compressor turns off electric as well as air supply.



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My shop was pre-plumbed for air distribution (copper pipes). The previous owner "isolated" the vibrating compressor from the relatively fragile copper pipe by using a ¾" by 36" hydraulic hose. When I replaced the compressor a couple months ago I also went to the local farm store and got a new hydraulic hose.

PS - Like yours, my compressor is in a separate enclosure. Being lazy, I designed a timer circuit that automatically opens the drain line for ~30 seconds each time the compressor starts. PM me if interested in the schematic.
 
So I wired it up #10 wire 20amp breaker into a Allen Bradley 3ph push button start switch with a light on one leg w/neutral
Used two terminals in switch , motor is a 5hp 220v marathon 1850rpm pt#97013270, motor plate has no amp rating. It dose have FLA 1.5 and SF 1.15 on it whatever that means?.
The new breaker trips when I push start, can’t imagine it uses more than 20amps to start. Any thoughts?.
 
It didn’t trip my 40amp welding circuit when plugged in.
 
The current to start a compressor tends to exceed nominal by 50%. That’s 25 amps for a 5hp motor. I have a 30 installed with the same size motor and it always works.

You can change the breaker with no problem because you used number 10 wire which is rated to 30amps.
 
I have the exact same compressor and it's set up with mag starter by the previous owner. I added a automatic drain set to 30 mins. It's on a 30 amp breaker. I've only had one problem with it in about 10 years, had to replace the pressure switch.

Mine keeps up with my bead blaster very well. You will like that compressor. I have mine in the furthest corner from where I work (about 30 feet away) and it's loud. I wish I could put it outside but my neighbor might not like that too much. But I don't like their barking dogs at all times of the day and night either.

I've found the best way to move mine is put an eye bolt in the motor and pump plate and use my engine crane on it.
 
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There should be a pressure relief to drain off air pressure between the pump & check valve. that way it starts with NO LOAD. As to the red light just buy a 220-volt bulb EZ peasy.
 
.... It dose have FLA 1.5 and SF 1.15 on it whatever that means? ....

FLA = Full Load Amps. The value 1.5 doesn't make sense for a 5 HP motor at 230 V. SF = Service Factor. The motor can (briefly) handle overloads to x1.15 of nominal horse power.
 
Thanks guys 30 amp breaker it will be. Anyone see a prob with a 5 watt led bulb on one leg ?.
 
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