Engineering manual - UniSAB III 1.10.8
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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.