Atlas Copco GA 18

Protections
For water-cooled compressors also: Minimum
setting
Factory
setting
Maximum
setting
Compressor element outlet temperature
(shutdown warning level)
˚C 50 110 114
Compressor element outlet temperature
(shutdown warning level)
˚F 122 230 237
Compressor element outlet temperature
(shutdown level)
˚C 111 115 115
Compressor element outlet temperature
(shutdown level)
˚F 232 239 239
Service plan
The built-in service timers will give a Service warning message after their respective pre-programmed time
interval has elapsed.
Also see section Preventive maintenance schedule.
Consult Atlas Copco if a timer setting has to be changed. The intervals must not exceed the nominal
intervals and must coincide logically. See section Modifying general settings.
Terminology
Term Explanation
ARAVF Automatic Restart After Voltage Failure. See section Elektronikon regulator and
Modifying general settings.
Power recovery
time
Is the period within which the voltage must be restored to have an automatic restart. Is
accessible if the automatic restart is activated. To activate the automatic restart function,
consult Atlas Copco.
Restart delay This parameter allows to programme that not all compressors are restarted at the same
time after a power failure (ARAVF active).
Compressor
element outlet
The recommended minimum setting is 70 ˚C (158 ˚F). For testing the temperature
sensor the setting can be decreased to 50 ˚C (122 ˚F). Reset the value after testing.
The regulator does not accept illogical settings, e.g. if the warning level is programmed
at 95 ˚C (203 ˚F), the minimum limit for the shutdown level changes to 96 ˚C (204 ˚F).
The recommended difference between the warning level and shutdown level is 10 ˚C
(18 ˚F).
Delay at
shutdown signal
Is the time for which the signal must exist before the compressor is shut down. If it is
required to program this setting to another value, consult Atlas Copco.
Oil separator Use only Atlas Copco oil separators. The recommended maximum pressure drop over
the oil separator element is 1 bar (15 psi).
Minimum stop
time
Once the compressor has automatically stopped, it will remain stopped for the minimum
stop time, whatever happens with the net air pressure. Consult Atlas Copco if a setting
lower than 20 seconds is required.
Unloading/
Loading pressure
The regulator does not accept inconsistent settings, e.g. if the unloading pressure is
programmed at 7.0 bar(e) (101 psi(g)), the maximum limit for the loading pressure
changes to 6.9 bar(e) (100 psi(g)). The recommended minimum pressure difference
between loading and unloading is 0.6 bar (9 psi(g)).
Instruction book
2920 7140 90 119