Troubleshooting guide

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· Node – These node address fields tell the se-
quencing algorithm which the MicroController
will be participating in the sequencing net-
work. Input the node addresses of each Con-
troller, participating on the network, in these
fields.
NOTE:
The node addresses for each panel are defined and
entered under the Setup screen at each individual
panel.
· Central Off/On Buttons – These buttons in-
dicate whether the compressor has been se-
lected to operate under Central Control. If
the button reads “On”, the compressor will be
included in the Central Control System. If the
button reads “Off”, the compressor will not
be included in the Central Control system.
Pushing once on the button will toggle the
button between “Off” and “On”.
· Priority – The Priority fields are used to as-
sign the compressor priority for Central Con-
trol. The lower the priority number, the greater
the priority of the compressor. Priority #1
compressor is the highest priority compres-
sor. Compressors with higher priority num-
bers will be lag compressors. A compressor
with a priority of 1 will be considered the
“lead” compressor. The suction pressure of
priority #1 compressor is used to control the
system pressure.
·
Step – This field sets the amount of capacity
change that will occur when a compressor is
loading or unloading.
NOTE:
Because of the method used to position the slide
valve, and the method used to determine when
the slide valve position is “close enough” to the
target value, the step value should never be less
than 5%.
· Min Cap – The Minimum Capacity is the lowest
capacity, in percentages, that this compressor is
allowed to reach during operation. If the system
needs to remove additional system capacity, it
may shut a compressor off.
·
Max Cap – The Maximum Capacity is the high-
est capacity, in percentage, that this compressor
is allowed to reach during operation. If the sys-
tem needs to increase capacity after this com-
pressor has reached its maximum, it may turn on
another compressor.
·
Stop Tmr – The Stop Timer (in seconds) is the
amount of time the system must hold a compres-
sor at minimum capacity before the compressor
can be shut off.
PRESSURE SETPOINTS:
The 7 pressure setpoints are used to control the
system pressure. With the exception of the Start #1
and Start Lag setpoints, all other setpoints must be
in decreasing pressures from the previous value.
·
Start #1 – The Start #1 pressure setpoint is the
system pressure at which the Priority 1 compres-
sor will be started.
·
Start Lag – The Start Lag pressure setpoint will
only start the lag compressor, and only after the
lead compressor has reached the Max Cap value,
and the Machine Start Timer has timed out. The
Lead compressor is normally priority, unless it is
not available to start due to waiting hot starts,
safety trips, etc.
·
Load Rate 2 – If the system pressure exceeds
the Load Rate 2 pressure setpoint for the time
specified in the Load Rate 2 Timer, Central Con-
trol will attempt to increase the capacity of the
system.
·
Load Rate 1 – If the system pressure exceeds
the Load Rate 1 pressure setpoint for the time
specified in the Load Rate 1 Timer, Central Con-
trol will attempt to increase the capacity of the
system.
Compressor Sequencing (Max 5 Compressors)