Johnson Controls SABROE Unisab III Control, Engineering Manual

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Engineering manual - UniSAB III 1.10.8
226/346
001930 en 2021.06
Set-up
To manually enable the Long Life function for upgraded, older compressors in the SMC Mk 4 family, the
commissioning engineer must log into the Superuser level with the appropriate password, and set the
SMC LL paramter to Yes .
Select No to deactivate the Long Life service intervals function.
6: Suction pressure gradient reset
0.0 to 20.0 *C [3.0 *C]
The
Suction pressure gradient reset parameter defines a minimum suction superheat limit for compres-
sor start.
This parameter is only active when the Suction pressure gradient limiter function is enabled.
At start-up, UniSAB III will check if the Suction superheat is lower than the Suction pressure gradient re-
set parameter. If this is the case, the compressor will not start. A Low suction superheat alarm will be is-
sued and compressor state will be set to Pause .
See subsection 6.4.3 Compressor block 22: Suction press. grad .
7: Yield rate up limitation
0.2 to 3.0 %/sec [2.0 %/sec]
The
Yield rate up limitation parameter defines the max. yield change per second with which the regula-
tors can increase the compressor Yield [%].
See subsection 3.2.3 Special limiters ; Yield decrease rate limiter .
8: Yield rate down limitation
0.2 to 3.0 %/sec [1.0 %/sec]
The
Yield rate down limitation parameter defines the max. yield change per second with which the regu-
lators can reduce the compressor Yield [%].
See subsection 3.2.3 Special limiters ; Yield decrease rate limiter .
6.4.8 External (User 1) input
See section 3.5 Compressor control - user functions .