Johnson Controls FRICK QUANTUM HD, Операция

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QUANTUM™ HD COMPRESSOR CONTROL PANEL
OPERATION
090.040-O (MAR 12)
Page 41
Dead Band Low - A band, measured in the
units of the Capacity Control setpoint, below
the setpoint at which the compressor will
neither load nor unload.
Cycle Time High - This setpoint determines
the amount of time in seconds that the load
or unload output is on and off, when in the
upper proportional band. Refer to the de-
scription below about cycle time.
Cycle Time Low - This setpoint determines
the amount of time in seconds that the load
or unload output is on and off, when in the
lower proportional band. Refer to the de-
scription below about cycle time.
Description Of Cycle Time: The Cycle
Time setpoint determines the total
amount of time for one on/off cycle,
when in the proportional band. At the
completion of the cycle time the ac-
tual reading and necessary response is
re-evaluated. If a four second period is
selected, then the following will result:
Proportional
Distance (Ac-
tual Reading is
From Setpoint)
Output
Pulsed
On
(seconds)
Output
Off
(seconds)
0 0 4
1/4 1 3
1/2 2 2
3/4 3 1
1 4 0
If a variable speed drive is used, the VSD
Proportional Band and Intergrated Time set-
points will be preset
[Proportional Band] – This setpoint
determines the size of a region either
above or below the Control Setpoint.
Within this region, the Proportional
component of the PI Output value is
the number between 0% and 100% that
directly corresponds to the difference
between the Control Input (Actual) and
the Control Setpoint (Setpoint). Outside
of this region, the Proportional compo-
nent is either 100% or 0%. If the PI’s
Action is Forward, the Proportional
Band extends above the Control Set-
point. If the PI’s Action is Reverse, the
Proportional Band extends below the
Control Setpoint.
[Integration Time] - This setpoint
controls the in fl uence that the Integral
component exerts on the PI Output
value. The Integral component works
to push the Control Input toward the
Control Setpoint by tracking the differ-
ence between the Control Input and the
Control Setpoint over time.
AUTOCYCLE - The following setpoint boxes are pro-
vided:
Start - The compressor turns on when the value
of the capacity control input reaches this set-
point. This setpoint is used in both AUTO (Au-
tomatic) or in REM SEQ (Remote Sequencing)
modes.
Start Delay – The time in minutes that the value
of the capacity control input must be above (for-
ward) or below (reverse) the start setpoint be-
fore the compressor will start.
Stop - The compressor is stopped when the
value of the capacity control input reaches this
setpoint. This setpoint is used in both AUTO
(Automatic) or in REM SEQ (Remote Sequenc-
ing) modes.
Stop Delay - The time in minutes that the value
of the capacity control input must be below (for-
ward) or above (reverse) the stop setpoint be-
fore the compressor will stop.
MODE SAFETIES
Load Inhibit - This setpoint prevents the com-
pressor from loading.
Force Unload - This setpoint will actively de-
crease the capacity of the compressor to avoid
reaching the warning and shutdown setpoints.
Warning - If the Capacity Control value is less
than (forward) or greater than (reverse) this set-
point for the Warning Delay, a warning occurs.
Shutdown - If the Capacity Control value is less
than (forward) or greater than (reverse) this set-
point for the Shutdown Delay, a shutdown oc-
curs.
LOW SUCTION - The following setpoint boxes are
provided (NOTE: This box will be empty if Suction
Pressure has been selected as the Mode control
channel):
Load Inhibit – As the suction pressure drops be-
low this setpoint, the compressor is prevented
from loading.
Force Unload – When the suction pressure
reaches this setpoint, the capacity of the com-
pressor will be decreased to avoid reaching the
low warning and shutdown setpoints.
Warning - If the Suction Pressure is less than
this setpoint for the Warning Delay, a warning
occurs.
Shutdown - If the Suction Pressure is less than
this setpoint for the Shutdown Delay, a shutdown
occurs.