Question MAKO 5405 HBA-05 Autodrain Issue

[PhilJM]

Hi everyone, i'm after a bit of advice and hopeful direction please.

We have a MAKO Compair 5405 compressor with autodrain that has recently developed a fault.

With the autodrain Solenoid plug connected, the compressor will start, run for 3-5 secs then shut down (no fault codes are shown on the controller).

With the plug disconnected, the compressor runs as normal and builds up to final pressure then shuts down (from the Pressure Valve).

We have fault investigated the 12V signal to the Solenoid, that is all correct and the StarDelta controller sends the signal to the solenoid at the correct intervals - we even checked the Star Delta Timer unit to make sure that the internals were working correctly, all is good on that front.

I've taken apart the autodrain box and inspected the No. 1 and No. 2 pistons and piston housing - no scores, debris or torn o-rings.

We've bench tested the 12V solenoid and it operates the piston correctly (as in retract it to open the drain system).

We're at a bit of a loss as every component "seems" to be serviceable and yet when it is all connected, the compressor only runs for 3-5secs.

Any ideas as to what the issue maybe?

The compressor has done approx 150Hrs and has a new filter changed approx 20 running hrs ago. All oil levels are correct (and correct oil type).

Thanks in advance!

 

[Wookie]

So I’ve been a Mako tech for 25 years. The ONLY thing I can think is that you have some kind of fault in the solenoid or solenoid plug, and when you pull the slug up it draws so much current that it drops the 12v to about 7 volts which drops out the starter. The 12v system won’t produce much current. I’ve dealt with lots of 5406 and greater with auto drain, very few 5405, but that’s the only thing I can think of. A multi-meter on the downstream side of the bridge rectifier measuring voltage will rule that problem out.

 

[PhilJM]

So I’ve been a Mako tech for 25 years. The ONLY thing I can think is that you have some kind of fault in the solenoid or solenoid plug, and when you pull the slug up it draws so much current that it drops the 12v to about 7 volts which drops out the starter. The 12v system won’t produce much current. I’ve dealt with lots of 5406 and greater with auto drain, very few 5405, but that’s the only thing I can think of. A multi-meter on the downstream side of the bridge rectifier measuring voltage will rule that problem out.

Thanks very much, I'll run the Compressor tomorrow and have the Fluke attached to see what the Volts are doing

 

[PhilJM]

Hi Wookie,

So we've just run the compressor with the Fluke attached.

Sequence of events:

Main power breaker on > start power button on > run button pressed > compressor starts and runs for 3 secs > issues occur!.

On compressor start, the Fluke shows 0V across the Autodrain Solenoid (which means the spring is holding it closed) and then after 3 secs, the controller sends a 12V signal to the Solenoid which opens the Solenoid.

Alongside this, a new issue has occurred.

We ran the compressor with the plug disconnected to the autodrain (just to confirm that the compressor continues to run and build pressure) and at the same time that the 12V signal is sent to the autodrain, a horrible actuator noise was heard from the C12 Relays in the control box.

It seems that the Allen Bradley C12 Relays that are in the control box are trying to both be engergised at the same time but the A02 actuator controller is preventing this (as it should according the to the manufacturer).

I've got a video of the relays doing their thing however it's 11Mb and too big to be attached.

Any further ideas as to what the root cause issue is? What i can't understand is that this compressor ran fine and worked perfectly last week, autodrain working as it should, good air being produced and now all of a sudden, this issue has occurred (no maintenance has been done on the compressor in the interim as I have sole access).