SRL Service Manual
Revision 00
July 2007
Page 22 of 56
4. Control System
The SRL-250 and larger dryers are fitted with microprocessor controls.
4.1 Power Supply
The following power supplies are offered on 60 Hz models:
•
230V/1ph/60Hz +/-10% on the SRL-250
•
230V/3ph/60Hz +/-10% on the SRL-250 through 800
•
460V/3ph/60Hz +/-10% on SRL-250 through 6000
•
575V/3ph/60Hz +/-10% on SRL-250 through 6000
All 50 Hz models are 400V/3ph/50Hz +/-10%.
4.2
Microprocessor Controls
The microprocessor controls on the Sullair SRL Dryers allow you to turn the dryer on and off, controls
the operation of the dryer, and continuously monitors the working parameters, informing the user of
possible problems through lights, alarms and a digital display.
In addition, the microprocessor also:
-
Records and displays the last 8 warnings or alarms,
-
Records the working hours of the dryer and of the refrigerant compressor,
-
Provides a Service Required warning at a pre-set interval,
-
Controls the cycling operation of the refrigerant compressor (SRL-325 & larger, when in Cycling
mode), and
-
Controls operation of the condensate drain.
The microprocessor can also be connected to an external Modbus RTU protocol compatible system
by installing an (optional) RS-485 communication port. See Section 10.5 for further information.
The electrical panel is located inside the dryer and positioned for easy access. It is directly accessible
from the front via a hinged door, with a door lock integrated into the dryer’s main switch.
The power section comprises a main isolator switch, protection against motor over current, and a
series of contactors.
