GA75 Element Outlet Pressure 9.0 bar - alarm

by Moses Yu
(Sibu, Sarawak, Malaysia)

Hi, recently one of my GA75 compressor was found high element outlet pressure 9.0 where setting only 2 bar limit.


Then, the compressor was stop and alarm "overload motor/fan motor".

May i know what is causing high element outlet pressure and will this relate to the alarm "overload motor/fan motor"?

Comments for GA75 Element Outlet Pressure 9.0 bar - alarm

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Dec 08, 2016
RE
by: Moses Yu

See my respond below:

You say that you have your compressor set to 2 Bar outlet pressure? Is this correct? That sounds very low? Or do you mean it is 2 Bar differential? What are you using the compressor for?

- Our system requirement for air pressure is about 7-8 bar and we set the load and unload pressure to 7.5 bar & 8.5 bar. Unfortunately i cant attach picture now. The reading i get from compressor monitor is shown as below which i cant understand it:

Element Outlet
bar 9.3
PeSt Max. 2.0

- Other compressors' element outlet only 1.7 bar. I did read something about back pressure 2 bar in the manual book but there is no further explanation on it.

Does the compressor pipework go into a receiver (Air Tank) then to your system? Do you have a dryer and/or filters connected to the system?

- Yes, we have air tank, dryer and filter (DD & PD) connected from compressor.

What pressure does the gauge read on the receiver? Does it match the pressure that the compressor makes?
Also, you should have a gauge inside the compressor attached to the Separator tank (where the oil goes) What does that gauge read when the compressor is on-load (making air)

-TBC

Dec 07, 2016
Element outlet pressure?
by: Carl

As far as the Element outlet pressure is concerned, it doesn't sound related to the fan motor overload.

A few questions...

You say that you have your compressor set to 2 Bar outlet pressure? Is this correct? That sounds very low? Or do you mean it is 2 Bar differential? What are you using the compressor for?

Does the compressor pipework go into a receiver (Air Tank) then to your system? Do you have a dryer and/or filters connected to the system?

What pressure does the gauge read on the receiver? Does it match the pressure that the compressor makes?
Also, you should have a gauge inside the compressor attached to the Separator tank (where the oil goes) What does that gauge read when the compressor is on-load (making air)

Dec 07, 2016
Fan motor
by: Carl

Check your fan motor, it sounds like it is failing, bearings possibly? As it is not working properly, causing it to overheat.

Dec 06, 2016
Re GA75 Element Outlet Pressure
by: Moses yu

In my monitor, there are 2 parameter monitored- compressor pressure & element outlet pressure.

Compressor pressure is controlled by load and unload pressure setting which now is currently set as 7.5 bar (load) to 8.5 bar (unload).

Element outlet pressure normally is only around 1.7 bar to 1.9 bar for my other 2 GA75 compressors. But this one is around 9 bar which is already above the setting limit (2 bar).

Actually I do not know what is this element outlet pressure refer to but since it was set by old time service technician years ago. Recently this compressor was tripped too frequently with "overload motor / fan motor" and that is the only deviation I found between the same type of compressors. We have already sent out the motor for repair and service 2 time due to this faulty.

Dec 06, 2016
Overpressure overload
by: Doug in s.d.ca

Sounds like the unloader solenoid/valve is stuck.

From the description you gave, it should have unloaded at 2 bar, right?

So, when that didn't happen it continued building to 9 bar and overloaded the motor, causing shutdown.

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