Electrical System; Regulation - Atlas Copco GA 110 VSD+ Instruction Book

• Check that a warning is generated on the display of the regulator.
• Release the test button.
7.5

Electrical system

Dryer protection
The high-pressure shut-down switch stops the compressor motor when the pressure in the
refrigerant circuit reaches the upper set-point of the switch.
After tripping:
• The switch must be reset manually by pressing its reset knob and by pressing the Cancel/
escape key on the controller.
The compressor motor has a built-in thermic protection. If the thermic protection trips, the
compressor motor will be stopped. The compressor will restart when the motor windings have
cooled down, which may take up to 3 hours.
7.6

Regulation

General description
The electronic regulator automatically controls the dryer, i.e.:
• keeps the pressure dew-point stable
• stops the dryer whenever necessary
• restarts the dryer when required
In general, the regulator has following functions:
• controlling the dryer
• protecting the dryer
Controlling the dryer
In order to keep the condenser pressure constant:
• For air-cooled versions, the regulator starts and stops the fan motor(s) as necessary.
• For water-cooled versions, the water regulating valve regulates the cooling water flow.
Protecting the dryer
Shut-down
• In case the pressure in the refrigerant circuit is too high, the dryer will be stopped.
• For air-cooled versions, the dryer will also be stopped if there is an overload of a fan motor.
Warning
• A warning message appears if the electronic water drain is malfunctioning.
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Instruction book
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