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SECTION 2 – OPTIVIEW CONTROL CENTER
FIGURE 34 - SETPOINTS SCREEN
This screen provides a convenient location for pro-
gramming the most common setpoints involved in the
chiller control. This screen also serves as a gateway to
a subscreen for defining the setup of general system
parameters.
DISPLAY ONLY
Leaving Chilled Liquid Temperature
Setpoint
Displays the present setpoint to which the chiller is
operating whether controlled remotely or locally. This
value could come from a 0-20 mA, 4-20 mA, 0-10
VDC or 2-10 VDC input in Analog Remote mode,
PWM signal in Digital Remote mode, SC-EQ commu-
nications interface in ISN (BAS) mode, or a locally
programmed value.
Remote Range
Displays the Remote Range which is set by the Local
Leaving Chilled Liquid Temperature Range setpoint.
It is a value between 10ºF and 40ºF added to the Lo-
cal LCHLT Setpoint defining the maximum Remote
LCHLT setpoint.
Leaving Chilled Liquid Temperature Cycling
Shutdown
Displays the Leaving Chilled Liquid Temperature at
which the chiller will shut down to avoid over-cooling
the building. This value is calculated by subtracting the
96
SETPOINTS SCREEN
Leaving Chilled Liquid Temperature Cycling Shut-
down Offset from the Leaving Chilled Liquid Tem-
perature Setpoint. If this value is below the absolute
minimum allowed shutdown temperature the mini-
mum value is displayed.
Restart
Displays the Leaving Chilled Liquid Temperature at
which the chiller will restart after it has shut down due
to cycling off on low water temperature. This value is
calculated by adding the Leaving Chilled Liquid Tem-
perature Cycling Restart Offset to the Leaving Chilled
Liquid Temperature Setpoint.
Chiller Current Limit Setpoint
Displays the current limit that is in effect during the
Chiller Steady State period (this period is in effect af-
ter the Chiller Pulldown Period is no longer in effect).
The Chiller Current Limit Setpoint could be from a
0-20 mA, 4-20 mA, 0-10 VDC or 2-10 VDC input in
Analog remote mode or PWM input in Digital remote
mode or SC-EQ communication interface in ISN (BAS)
remote mode or a Local Chiller Limit Setpoint entered
at the Keypad. The Chiller Pulldown Period is in effect
from the instant the chiller enters "System Run" until
the Leaving Chilled Liquid Temperature is within 2ºF
of the Leaving Chilled Liquid Temperature Setpoint.
During this period, the Chiller Pulldown Demand Limit
Setpoint is in effect. The Chiller Current Limit Setpoint
is in effect for the remainder of "System Run".
FORM 160.79-O3
ISSUE DATE: 11/09/2018
LD27873
JOHNSON CONTROLS
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