Johnson Controls SABROE UniSAB III User Manual

Engineering manual - UniSAB III 1.10.8
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001930 en 2021.06
Set-up
8: Vi mode
70 to 97%
Only relevant for screw compressors with electrical slide control. See subsection 3.9.1 Electrical slide
control.
9: Mechanical zero
No
Yes
Mechanical zero must only be set to Yes if the compressor has a built-in spacer block and automatic Vi
regulation. This way the travel of the capacity slide is automatically reduced by the percentage (0-40%)
entered in Manual zero. Thus corrected capacity is calculated and shown correctly.
10: Manual zero
0 to 40%
For screw compressors without automatic zero point setting, it is possible to manually set a "zero point"
below which the compressor capacity slide is not allowed to fall during compressor operation.
If the compressor has a built-in spacer block and automatic Vi regulation, Manual zero is used to reduce
the travel of the capacity slide by the entered percentage. Thus corrected capacity is calculated and
shown correctly. The value [0-40%] to be entered in Manual zero must be of the following size:
See Table 51: Maximum movement of capacity slide.
For SAB 202, which has automatic zero point setting, the value 0% must be kept. See also 6: Mechani-
cal zero.
For SAB 120, 151, 193, 233, 283, 355 the configuration of Manual zero is now made automatically when
Rotatune is selected. See subsection 6.4.1 Drive6: Rotatune. The automatic configuration of Manual
zero may still be changed manually, but the setting will be overwritten after a restart.
11: Capacity zero
0 to 60% (default: 0%)
For screw compressors type SAB 193 H→355 H without VSD it is possible to set a "zero point" capacity
limit, below which the compressor slide capacity is not allowed to fall during normal compressor opera-
tion. This configuration point is fixed at the default value, and may only be changed by a Johnson Con-
trols supervisor. When the Capacity zero parameter is set to 0%, the Capacity zero function is not
active, meaning the capacity zero function is deactivated as default.
Note: However, in software version 1.10.7, the Capacity zero parameter is default set to 60%, meaning
the Capacity zero function is activated.
12: Booster (screw compressors)
No
Yes
Yes means that the oil pump will run continuously during compressor operation. This allows the capacity
slide to be moved at low pressure conditions.
Note: SAB Mk 3, SAB HR, SAB 202, VMY Mk 3, SV/FV and GSV/SGC compressors are fitted with dif-
ferential pressure controlled oil pumps and do therefore not use this configuration point.
Manual zero =
Max. movement of capacity slide
Length of spacer block x 100

Johnson Controls SABROE UniSAB III Specifications

General

Brand	Johnson Controls
Model	SABROE UniSAB III
Category	Control Systems
Language	English