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SECTION 2 - OPTIVIEW CONTROL CENTER INTRODUCTION
Leaving Chilled Liquid Temperature Setpoints
– Shutdown
Displays the Leaving Chilled Liquid Temperature at
which the chiller will shutdown on Leaving Chilled
Liquid – Low Temperature. This temperature is en-
tered as an offset with the Leaving Chilled Liquid Tem-
perature Cycling Offset – Shutdown Setpoint below.
Although the offset setpoint is changed manually, the
offset being used can change automatically to prevent
the Leaving Chilled Liquid Temperature from going
below the minimum allowed value: 36°F (water), 34°F
(water with smart freeze enabled) or 6°F (brine). The
offset being used is displayed as Effective Offset.
Leaving Chilled Liquid Temperature Setpoints
– Restart
Displays the Leaving Chilled Liquid Temperature at
which the chiller will restart after it has shutdown on
LEAVING CHILLED LIQUID – LOW TEMPERA-
TURE cycling shutdown. This temperature is set as an
offset using the Leaving Chilled Liquid Temperature
Cycling Offset – Restart Setpoint, displayed as OFF-
SET adjacent to this value.
PROGRAMMABLE
Local Leaving Chilled Liquid Temperature –
Range
Access Level Required: OPERATOR
This is the range over which an analog (0 to 20mA, 4 to
20mA, 0 to 10VDC or 2 to 10VDC) in Analog Remote
mode or a digital signal (PWM) in Digital Remote
mode can reset the Leaving Chilled Liquid Tempera-
ture Setpoint above the operator programmed BASE
Setpoint. Programmable as 10, 20, 30 or 40°F. It is add-
ed to the BASE value to create a range over which the
remote device can reset the setpoint. For example, if
this setpoint is programmed for 10°F and the operator
programmed value is 45°F, then the remote device can
set the Leaving Chilled Liquid Temperature Setpoint
over the range of 45.0° to 55.0°F.
30
Local Leaving Chilled Liquid Temperature –
Setpoint
Access Level Required: OPERATOR
This value allows the user to define the Leaving
Chilled Liquid Temperature that is to be maintained
by the chiller. It is programmable over the range of
38.0°F to 70.0°F (water) or 10.0°F to 70.0°F (brine).
If Smart Freeze (refer to Page 31) is enabled, the
range is 36.0°F to 70.0°F (water). A remote device can
provide an analog signal (0 to 20mA, 4 to 20mA, 0
to 10VDC or 2 to 10VDC) in Analog Remote mode,
or PWM signal in Digital Remote mode that chang-
es the setpoint by creating an offset above the op-
erator programmed BASE Leaving Chilled Liquid
Temperature Setpoint. This offset may be defined as
10, 20, 30, or 40°F above the BASE Setpoint (refer
to the Leaving Chilled Liquid Temperature Setpoints
– Setpoint on Page 29 description). Additionally,
an E-Link or SC-Equip Gateway (in ISN Remote mode)
can define the setpoint through a serial data stream. In
this case, the incoming setpoint is not an offset that
is applied to the locally programmed BASE Setpoint
value, but rather is the setpoint value itself.
Leaving Chilled Liquid Temperature Cycling
Offset – Shutdown
Access Level Required: OPERATOR
This value allows the user to specify the Leaving
Chilled Liquid Temperature at which the chiller will
shut down on a LEAVING CHILLED LIQUID – LOW
TEMPERATURE cycling shutdown. This is done by
defining an offset below the Leaving Chilled Liquid
Temperature Setpoint. It is programmable over a range
of 1°F to 64°F below the setpoint, to a minimum cut-
out of 36°F (water), 34°F (water with Smart Freeze
enabled) or 6°F (brine). Anytime the Leaving Chilled
Liquid Temperature Setpoint is increased, the setpoint
is increased at a rate of 0.2°F per second to allow the
chiller time to unload.
The offset being used is displayed as Effective Offset
in the upper right area of the display. Usually, the Off-
set used is the same as the value programmed for the
Shutdown Setpoint. However, the Offset being used
will automatically change based on the values pro-
grammed for the Leaving Chilled Liquid Temperature
Setpoint and the Shutdown Setpoint, to prevent the
Leaving Chilled Liquid Temperature from going below
the minimum allowed value: 36°F (water), 34°F (water
FORM 160.87-OM1
ISSUE DATE: 8/24/2018
JOHNSON CONTROLS
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