55
STARTUP DELAY IN EFFECT — This mode is checked
for when the unit is started. This mode is active when the Min-
utes Off Time (
Unit Off to On Delay
, DELY
) timer is active.
The unit will not start until the timer has expired. The mode
will terminate when the timer expires.
SECOND SETPOINT IN USE — This mode is checked for
when the unit is ON. The mode is active when Cooling Set-
point 2 (
Cooling Setpoint 2
,
CSP.2
) or Ice Setpoint (
Cooling
Ice Setpoint
, CSP.3
) is in use. While in this mode, the Active
Setpoint (
Current Setpoint
, SETP
) will show the
CSP.2
or
CSP.3
value.
While in this mode, the unit will operate to the Cooling Set-
point 2 (
CSP.2
) or Ice Setpoint (
CSP.3
). The mode will termi-
nate when the Cooling Setpoint 2 (
CSP.2
) or Ice Setpoint
(
CSP.3
) is no longer in use.
RESET IN EFFECT — This mode is checked for when the
unit is ON. The mode will be active when Temperature Reset
(
Cooling Reset Select
, CRST
) is enabled either by
CRST
=1
(Outside Air Temperature),
CRST
=2
(Return Water),
CRST
=3
(4-20 mA Input), or
CRST
=4
(Space Temperature) and reset is
active.
While in this mode, the Active Setpoint (
Current Setpoint
,
SETP
) will be modified according to the programmed infor-
mation and will be displayed as the Control Point (
Control
Point
, CTPT
). The mode will terminate when the Temperature
Reset is not modifying the active leaving water set point, caus-
ing
SETP
to be the same as
CTPT
.
DEMAND LIMIT ACTIVE — This mode is checked for
when the unit is ON. The mode is active when Demand Limit
(
Demand Limit Type Select
, DMDC
) is enabled either by
DMDC
=1
(Switch),
DMDC
=2
(4-20 mA Input), or the Night
Time Low Sound Capacity Limit (
Capacity Limit
, LS.LT
).
The Active Demand Limit Value (
Active Demand Limit
Val
, LIM
) will display the current demand limit according to
the programmed information and the unit’s capacity will be re-
duced to the amount shown or lower. The mode will terminate
when the Demand Limit command has been removed.
RAMP LOADING ACTIVE — This mode is checked for
when the unit is ON. The mode is active when Ramp Loading
(
Ramp Loading Select
, RL.S
) is enabled and the following
conditions are met:
1. The leaving water temperature is more than 4° F (2.2° C)
from the Control Point (
Control Point
, CTPT
), and
2. The rate of change of the leaving water temperature is
greater than the Cool Ramp Loading (
Cooling Ramp
Loading
, CRMP
).
The control will limit the percent capacity increase until one
of the two conditions above are no longer met, then the mode
will terminate.
COOLER PUMPS ROTATION — This mode is checked for
whether the unit is ON or OFF. The mode is active when the
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.
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
released.
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
checked for whether the unit is ON or OFF. The mode is active
when the condenser pump sequence (
Condenser Pump
Sequence,
HPUM
= Yes
) and the pump rotation delta timer
(
Pump Auto Rotation Delay,
ROT.P
) have expired.
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 Set-
point (
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
These modes are checked when the circuit is ON. The
appropriate circuit mode will be active if one of the follow-
ing 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.