Johnson Controls SABROE Unisab III Control, Инструкция по эксплуатации

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Engineering manual - UniSAB III 1.10.8
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001930 en 2021.06
Compressor control and surveillance
Before start-up, and if the configuration parameter Suction press. grad. is enabled, UniSAB III will check
if the Suction superheat is lower than the Suction pressure gradient reset parameter. If this is the case,
the compressor will not start. A Low suction superheat alarm will be issued and compressor state will be
set to Pause .
Running
After the starting sequence and during normal running operation, the slide capacity must be higher than
the minimum capacity, i.e. the configuration limit
Manual zero .
For compressors without VSD, Manual zero is default 30% and for compressors with VSD drive, Manual
zero is calculated automatically.
For software version 1.10.7, the following applies: after the starting sequence and during normal running
operation, the slide capacity must be higher than the configuration limit
Capacity zero - for compressors
without VSD (default 60%) and for compressors with VSD drive (100%).
Alarm surveillance
Low oil pressure 45 sec.
High filter diff. pressure 600 sec.
Low superheat 300 sec.
High superheat 300 sec.
Low/high oil temperature 300 sec.
The delayed alarms are described in section 6.5 Timers.
Stopping sequence
Under normal running conditions, SAB 193 H, 233 H, 283 H, and 355 H compressors will stop when they
are under 5% above their minimum capacity, i.e. the configuration limit
Manual zero.
When the compressor has been stopped, the capacity slide will be moved below 5% slide capacity. The
solenoid valves for decreasing capacity and Vi position are activated for maximum 300 seconds. If the
capacity slide is not below 5% within the 300 seconds, a
Capacity error shutdown will be issued.
For software version 1.10.7, the following applies: for compressors without VSD drive, the stop criteria is
Capacity zero + 5% and for compressors with VSD drive, the stop criteria is Motor rpm min/Motor rpm
max + 5%. When a limiter function is active, the stop criteria is 5% Yield.
Balance piston
For SAB 193 H - 355 H, the AUX output is dedicated for control of the balance piston. Choose the AUX
output to be activated
At bal. cap. in the menu Compressor control – user functions and set the Signal
high limit and the Signal low limit.
For more information about the AUX output function, see also subsection 3.5.6 Aux. output .
3.3.23 SAB 273 S
The SAB 273 S type compressor is a high-pressure screw compressor. The compressor is equipped
with capacity slide and automatic Vi-control.
If the compressor is equipped with a frequency converter (VSD), see subsection 6.4.1 Drive ; 6: Rotatune
for additional set-up of UniSAB III.
If the compressor is equipped with oil pump, the oil pump is used for maintaining a minimum oil pressure
level during operation and for returning the capacity slide to minimum position before the compressor is
started: