SABROE UNISAB S-Control, Инструкция по эксплуатации

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0171-761-EN
The start sequence no. and the system no.
must be coded into each UNISAB S-Con-
trol.
As can be seen in the table for system no. 1,
compressor no. 1 has been allocated start
sequence no. 2. Compressor number 2 has
been allocated start sequence no. 3 and so
on. This means that compressor no. 5 will
start first, compressor no. 1 will start next,
then compressor no. 2.
If the capacity requirement increases, each
compressor will increase capacity to 100%
before the next compressor starts. The two
compressors which were coupled in last will
run at the same capacity.
If the capacity requirement falls, so that the
compressor with the lowest start sequence
number can manage the load, the capacity
on the compressor which can stop will be
reduced until it runs at 0%. After it has run
at 0% for five minutes (
delay before stop
timer) the compressor will stop.
The system will ignore one or more com-
pressors in
alarm situation, or if they have
been changed to manual operation . The
compressors remaining in the system will
still be regulated.
A compressor which has been RESET after
an alarm, or changed from manual to auto-
matic operation, will resume its position in
the sequence after some time. On system no.
2 compressor no. 3 has start sequence no. 1
and compressor no. 4 has start sequence no.
2.
As an example, system no. 1 and 2 could be
high pressure and booster system respec-
tively. If there is a need for changing a
compressor from one system to another, the
start sequence no. and the system no. must
be changed, but NEVER the compressor no.
Remember to change the set point for the
regulator as well.
On each system the regulator in the
UNISAB S-Control with the lowest com-
pressor no, is used for regulating all the
UNISAB S-Controls in this system. If the
UNISAB S-Control with the lowest com-
pressor no is switched off, the regulator on
the UNISAB S-Control with the next larger
no. is used, and it is unpractical if it has a
wrong set point!
Please observe that two compressors can
have the same start sequence no. as long as
they belong to two different systems.
NB
Two compressors must NEVER have the
same compressor no., as it is used as a
con-
tact no . for communication between the
UNISAB S-Controls.
Local automatics
Normally, when several UNISAB S-Con-
trols are coupled together, one UNISAB
S-Control regulates all compressors, as de-
scribed above. However, if a UNISAB
S-Control is set to
local automatic opera-
tion it will be controlled by its own regula-
tor. Commands from a host computer will
be ignored. Select
automatic operation
(no
light in LED) by using the control field.
Set the start sequence number to 0.
The UNISAB S-Control must be in automa-
tic operation for this function to apply. The
start sequence no. has no influence in manu-
al operation.