Operating instructions

70
Cooler Pump Sequence (Cooler Pump Run Status,
PUMP=2) (2 Pumps Automatic Changeover) and the Pump
Rotation Delta Timer (Pump Auto Rotation Delay, ROT.P)
have expired.
The control will switch the operation of the pumps. The
lead pump will operate normally. The lag pump will be started,
becoming the lead, and then the original lead pump will be shut
down. This mode will terminate when the pump operation has
been completed.
PUMP PERIODIC START — This mode is active when the
cooler pump is started due to the Periodic Pump Start configu-
ration (Pump Sticking Protection, PM.PS=YES). If the pump
has not run that day, a pump will be started and will run for 2
seconds at 2:00 PM. If the machine is equipped with dual
pumps, Pump no. 1 will run on even days (such as day 2, 4, 6
of the month). Pump no. 2 will run on odd days (such as day 1,
3, 5 of the month). The mode will terminate when the pump
shuts down.
NIGHT LOW NOISE ACTIVE — This mode is active when
the Night Time Low Noise Option has been configured and the
current time is within the configured time frame. Programming
a Night Low Noise Start Time (Start Hour, LS.ST) and a
Night Low Noise End Time (End Hour, LS.ND) configures
the option.
The control will raise the head pressure set point to reduce
the number of condenser fans on, thereby reducing the sound
level of the machine. Additionally, if the Night Time Low
Sound Capacity Limit (Start Hour, LS.LT) has been config-
ured, the unit’s capacity will be limited to the programmed lev-
el. This mode will terminate once the Night Low Noise End
Time (LS.ND) has been reached.
SYSTEM MANAGER ACTIVE — This mode is checked
when the unit is ON or OFF. This mode is active if a System
Manager such as Building Supervisor, Chillervisor System
Manager, or another CCN device is controlling the machine.
When this mode is active, the machine will respond to the
specific commands received from the System Manager. The
mode will be terminated if the System Manager control is re-
leased.
MASTER SLAVE CONTROL ACTIVE — This mode is
checked for if the machine is ON. This mode is active if Master
Slave Control has been enabled. This occurs when two ma-
chines are programmed, one as the master (Master/Slave Se-
lect, MSSL=1 [Master]) and the other as a slave (Master/
Slave Select, MSSL=2 [Slave]).
Both the master and slave machines will respond to the ca-
pacity control commands issued by the master controller. This
may include control point changes and demand limit com-
mands. This mode will terminate when Master Slave Control
has been disabled.
AUTO CHANGEOVER ACTIVE — This mode is not
supported.
FREE COOLING ACTIVE — This mode is not supported.
RECLAIM ACTIVE — This mode is not supported.
ELECTRIC HEAT ACTIVE — This mode is not supported.
HEATING LOW EWT LOCKOUT — This mode is not
supported.
CONDENSER PUMPS ROTATION — This mode is not
supported.
ICE MODE IN EFFECT — This mode is checked for when
the unit is ON. This mode is active when Ice Setpoint (Cooling
Ice Setpoint, CSP.3) is in use. While in this mode, the Active
Setpoint (Current Setpoint, SETP) will show the Cooling Ice
Setpoint, CSP.3, value and the unit will operate to the Ice
Setpoint (
CSP.3). This mode will terminate when the Ice
Setpoint (CSP.3) is no longer in use.
DEFROST ACTIVE ON CIR A — This mode is not
supported.
DEFROST ACTIVE ON CIR B — This mode is not
supported.
LOW SUCTION CIRCUIT A
LOW SUCTION CIRCUIT B
LOW SUCTION CIRCUIT C — These modes are checked
when the circuit is ON. The appropriate circuit mode will be
active if one of the following conditions is true:
1. If the circuit’s saturated suction temperature (SST) is
more than 6° F (3.3° C) less than the freeze point and
both the cooler approach (Leaving Water Temperature –
SST) and superheat (Suction Gas Temperature – SST) are
greater than 15° F (8.3° C).
2. If the circuit is ON and the circuit’s SST is more than
18º F (10.0º C) below the freeze point for more than
90 seconds.
3. If the circuit’s saturated suction temperature is more
than 6° F (3.3° C) below the freeze point for more than
3 minutes.
For a fresh water system (Cooler Fluid Type, FLUD =1),
the freeze point is 34° F (1.1° C). For medium temperature
brine systems, (Cooler Fluid Type, FLUD=2), the freeze point
is Brine Freeze Set Point (Brine Freeze Setpoint, LOSP).
For criterion 1, no additional capacity will be added. For cri-
teria 2 and 3 capacity will be decreased on the circuit. The
mode will terminate when the circuit’s SST is greater than the
freeze point minus 6° F (3.3° C) or the circuit has alarmed.
If this condition is encountered, see Possible Causes for
Alarms 56-58 on page 98.
HIGH DGT CIRCUIT A — This mode is not supported.
HIGH DGT CIRCUIT B — This mode is not supported.
HIGH DGT CIRCUIT C — This mode is not supported.
HIGH PRES OVERRIDE CIR A
HIGH PRES OVERRIDE CIR B
HIGH PRES OVERRIDE CIR C — This mode is checked
for when the circuit is ON. The appropriate circuit mode will
be active if the discharge pressure for the circuit, Discharge
Pressure Circuit A (Discharge Pressure, DP.A), Discharge
Pressure Circuit B (Discharge Pressure, DP.B), or Discharge
Pressure Circuit C (Discharge Pressure, DP.C), is greater than
the High Pressure Threshold (High Pressure Threshold,
HP.TH).
The capacity of the affected circuit will be reduced. Two
minutes following the capacity reduction, the circuit’s saturated
condensing temperature (SCT
t+2
) is calculated and stored. The
affected circuit will not be allowed to add capacity for at least 5
minutes following the capacity reduction. If after 5 minutes,
the circuit’s saturated condensing temperature is less than
SCT
t+2
–3° F (1.7° C), and then if required, percent capacity
will be added. If additional capacity is required, the control will
look for other circuits to add capacity.
This mode will terminate once the circuit’s saturated con-
densing temperature is less than SCT
t+2
–3° F (1.7° C).
If this condition is encountered, see Possible Causes for
Alarm A1.03. on page 103.
LOW SUPERHEAT CIRCUIT A
LOW SUPERHEAT CIRCUIT B
LOW SUPERHEAT CIRCUIT C — This mode is checked
for when the circuit is ON. The appropriate circuit mode will
be active if the circuit’s superheat (discharge gas temperature –
SCT) is less than 18° F (10° C).