Engineering manual - UniSAB III 1.10.8
001930 en 2021.06
201/346
The above is not relevant for plants consisting of reciprocating compressors without VSD only. See the
swept volume on the compressor name plate.
3: Volume ratio (screw compressors)
Manual
Auto
If selecting
Auto
, the compressor must be fitted with solenoid valves etc for automatic regulation of Vi
slide.
4: Fixed Vi ratio
1.4, 1.7, 2.2, 2.9, 3.4, 4.0
For SAB 157 HR high-pressure screw compressors of the HPSH type with fixed Vi ratio, select the cor-
rect
Fixed Vi ratio
for this compressor block. The fixed Vi ratio is stamped on the compressor block.
5:Vi comp. plug valve
No
Yes
Select
Yes
if you wish to use the plug valve to optimise the Vi ratio at part load in case the compressor is
operating at a lower Vi ratio than the block is designed for. This gives lower power consumption, but
might lower the maximum compressor capacity too.
Select
No
if you do not wish to use the plug valve to optimise the Vi ratio at part load.
6: Vi low range
Yes
No
Select
Yes
for types SAB 193 S - SAB 355 X with low volume range (1.7-3.0), SABflex and SABCube
compressors with low volume range. See volume range on compressor name plate. Select
No
for all
other compressor types.
7: Vi trig level
2.5/3.6
This setting is for SABflex and SABCube screw compressors. It defines the Vi trig level where the Vi
slide output is set to low or high. The Vi trig level depends on the setting of the
Vi low range
. Not
changeable.
Summary of Contents for SABROE Unisab III Control
Page 1: ...UniSAB III control Version 1 10 8 Engineering manual EN...
Page 2: ......
Page 347: ......
