Setpoints Screen; Figure 28 - Setpoints Screen - York YST Operation Manual

FORM 160.67-O1
ISSUE DATE: 4/1/2015
noTe: OptiView Control Center Screens shown may NOT represent the exact screens according to the software version utilized.
™

figure 28 - SeTpoinTS SCreen

overvieW
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 sub-screen for defining the setup of general system
parameters alarm and shutdown setpoints, and miscel-
laneous configuration.
diSplaY onlY
Leaving Chilled Liquid Temperature - Setpoint Dis-
plays the present setpoint to which the chiller is operat-
ing whether controlled remotely or locally. This value
could come from a 0-20 mA, 4-20 mA, 0-10VDC or
2-10VDC input in Analog Remote mode, PWM signal
in Digital Remote mode, MicroGateway interface in
ISN mode, or a locally programmed value.
leaving Chilled liquid Temperature Cycling -
Shutdown
Displays the Leaving Chilled Liquid Temperature at
which the chiller will shut down to avoid over-cool-
ing the building. This value is calculated by subtract-
ing the Leaving Chilled Liquid Temperature Cycling
Offset – Shutdown from the Leaving Chilled Liquid
Temperature – Setpoint. If this value is below the abso-
lute minimum allowed shutdown temperature the mini-
mum value is displayed.
JOHNSON CONTROLS
SECTION 2 - OPTIVIEW CONTROL CENTER INTRODUCTION

SeTpoinTS SCreen

leaving Chilled liquid Temperature Cycling –
restart
Displays the Leaving Chilled Liquid Temperature at
which the chiller will restart after it has shut down due
to over-cooling temperature. This value is calculated
by adding the Leaving Chilled Liquid Temperature Cy-
cling Offset – Restart to the Leaving Chilled Liquid
Temperature – Setpoint.
prograMMable
local leaving Chilled liquid Temperature -
range
Access Level Required: OPERATOR
This is the range over which an analog signal (0-20
mA, 4-20 mA, 0-10VDC or 2-10VDC) in Analog Re-
mote Mode or a digital signal (PWM) in Digital re-
mote mode can reset the Leaving Chilled Liquid Tem-
perature setpoint above the operator programmed Base
Setpoint (see below). Programmable as either 10°F or
20°F, with a default of 20°F, it is added 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 Leav-
ing Chilled Liquid Temperature setpoint over the range
45.0°F - 55.0°F.
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