Johnson Controls SABROE UniSAB III Engineering Manual page 135

Compressor control and surveillance
When the compressor is equipped with VSD and the soft Centa coupling one of the following unloading
functions must be chosen:
• VSD normal – see subsection 6.4.3 Compressor block.
• VSD total – see subsection 6.4.3 Compressor block.
Additional unloading is not available with Centa coupling.
Table 29 shows SMC VSD cylinder unloading with the Centa coupling. Percentages shown are the ca-
pacity at maximum speed.
Cylinders 2
Compressor
SMC/HPC 104
HPX 704
DO09
Digital output
SMC/HPC 106
HPX 706
DO09
Digital output
SMC/HPC 108
HPX 708
DO09
Digital output
TSMC 108
-
Digital output
SMC/HPC 112
HPX 712
-
Digital output
SMC/HPC 116
HPX 716
-
Digital output
TSMC 116 *)
Digital output
-
Table 29: SMC VSD cylinder unloading configuration with Centa coupling
The digital output and solenoid valves which must be activated to provide capacity control are emphas-
ised with bold letters.
The Thermo Pump TPV connection for the high cylinder part is also shown in Table 29. The TPV con-
nection has not been changed - it is the same as for the standard compressor.
*) Note that on a standard TSMC 116 compressor, output DO09 will correspond to 33% (4+2 cylinders).
With VSD unloading, DO09 will correspond to 17% (2+2 cylinders).
Engineering manual - UniSAB III 1.10.8
001930 en 2021.06
4 6 8
100%
1
DO10
100%
1
DO10
DO11
50% 100%
2 1+2
TPV (1)
DO11
DO10 +DO12
33% 100%
2 1+2
DO10
DO09 +DO11
50%
TPV (1)
2
DO9 DO11
DO10
25% 50%
4 3+4
DO10
DO09 +DO11
17% 50%
4 3+4
-
DO09 +DO10
135/346
10 12 14
100%
1+2
DO12
+DO13
75%
TPV
2+3+4
(1+2)
DO12 DO14
+DO13
67%
2+3+4
TPV
-
(2HP)
DO12
+DO11
16
100%
1+2+3+4
+DO15
100%
1+2+3+4
+DO13