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SECTION 2 - OPTIVIEW CONTROL CENTER INTRODUCTION
DISPLAY ONLY
Leaving Chilled Liquid Temperature
Displays the temperature of the liquid as it leaves the
evaporator.
Leaving Chilled Active Setpoint
Displays the setpoint to which the Leaving Chilled
Liquid is being controlled.
Quick Pulldown in Effect (LED)
Illuminates while a Quick Pulldown is in effect. This is
in effect from a start initiate until the Quick Pulldown
Setpoint Offset has been reached or the Pulldown
Override Time has elapsed, whichever occurs first.
For fields requiring access level of SER-
VICE. Qualified service technicians should
refer to the OptiView Control Center
Service for operation instructions and ex-
planations of all programmable setpoints
and displayed values.
PROGRAMMABLE
Change Setpoints
Access Level Required: SERVICE
Used to enter the following setpoints. Pressing this key
places a green selection box around the first change-
able setpoint. Use the ▲ and ▼ keys to place the selec-
tion box around the desired setpoint. With the setpoint
selected, press the ENTER () key. A dialog box ap-
pears with the range of settings.
Quick Start Mode
Access Level Required: ADMIN
This setpoint is used to Enable and Disable the Quick
Start feature. It can only be Enabled when the Motor
Drive Type Setpoint is set to VSD or MVVSD and the
Motor Communications Protocol is set to Modbus.
The default is Disabled. Quick Start can only be en-
abled using an ADMIN password. When logged in at
ADMIN access level, a QUICK START key will ap-
pear on the SETPOINTS Screen. Pressing this key
will navigate to the QUICK START Screen where this
setpoint is used to enable/disable the feature.
124
Quick Start can be Disabled when logged in at SER-
VICE access level. However, once Disabled, it re-
quires an ADMIN password to enable it again, as ex-
plained above. Quick Start mode will be automatically
disabled when any of the following occur: The Motor
Drive Type is changed to something other than VSD
or MVVSD, or the Motor Communications Protocol is
changed to YORK.
Quick Pulldown Setpoint Offset
Access Level Required: SERVICE
This setpoint sets the Leaving Chilled Liquid Tempera-
ture at which the control transitions from Quick Start
mode to normal operation. It is entered in the form
of an offset above the active Leaving Chilled Liquid
Temperature (LCHLT) Setpoint. Once the Leaving
Chilled Liquid Temperature falls below the Active
LCHLT Setpoint plus Quick Pulldown Setpoint Off-
set, PRV (Quick Restart) and speed control (Quick
Restart and Quick Normal Start) revert to normal au-
tomatic control. Lower values of this offset result in
faster pulldown times but can result in overshoot of the
LCHLT Setpoint. Setting the value to its minimum of
0 results in the fastest pulldown time but nearly always
results in setpoint overshoot. Depending upon how
close the Low Chilled Liquid Temperature shutdown
threshold is to the LCHLT Setpoint, this could result in
a LOW CHILLED LIQUID TEMPERATURE cycling
shutdown. (0°F to 10°F; default 5°F)
The Leaving Chilled Liquid Temperature and setpoint
is shown on the QUICK START Screen for reference.
This setpoint sets one of the two setpoints that deter-
mine when the control transitions from Quick Start
mode to normal operation. The other is the Pulldown
Override Time below.
Pulldown Override Time
Access Level Required: SERVICE
This setpoint is the length of time the PRV is held open
(Quick Restart) and the ACC speed (Quick Restart and
Quick Normal Start) is increased on startup if the Quick
Pulldown Setpoint Offset is not reached. This could be
due to hitting current limit during the pulldown. If the
Quick Pulldown Setpoint Offset is not reached in the
Pulldown Override Time, PRV and ACC speed control
will revert back to normal automatic control. (0 min to
15 min; default 10 min)
FORM 160.87-OM1
ISSUE DATE: 8/24/2018
JOHNSON CONTROLS
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