York YK-EP B Operation & Maintenance Manual page 35

FORM 160.87-OM1
ISSUE DATE: 8/24/2018
The actual value of the output signal for a given error
depends on whether the PID OUTPUT Setpoint is set
to direct or reverse. If set to direct, the 0.0% output will
be at minimum; the 100% output will be at maximum.
If set to reverse, the 0.0% output will be at maximum;
the 100% output will be at minimum.
Control Valve Control Mode
Displays whether the Control Valve is in automatic or
manual control.
PROGRAMMABLE
Head Pressure Setpoint
(15.0 to 60 PSID; default 23.0 PSID) Sets the pressure
differential to which the Control Valve will control the
Head Pressure.
Minimum Position
(0 to 100%; default 0%) Sets the minimum position
that the valve can drive to while the chiller is running.
Shutdown Position
(0 to 100%; default 0%) Sets the position that the valve
will drive to while the chiller is off.
Control Valve Output Settings – Type
(0-10v or 4 to 20mA; default 0-10v) Sets the output
signal to the Control Valve to be in the form of either 0
to 10VDC or 4 to 20mA.
Control Valve Output Settings – Direction
(Direct or Reverse) Allows the output signal to the
Control Valve to be set to direct or reverse acting.
When set to direct, the voltage or current signal to the
Control Valve is at minimum for a 0% command and at
maximum for a 100% command. When set to reverse,
the voltage or current signal to the Control Valve is at
maximum for a 0% command and at minimum for a
100% command.
Control Valve Output Settings – Set
(0.0% to 100%; default 0.0%) Allows the Control
Valve to be manually set to a position between 0.0%
and 100%.
JOHNSON CONTROLS
SECTION 2 - OPTIVIEW CONTROL CENTER INTRODUCTION
Control Valve Output Settings – Auto
Places the Control Valve in automatic control.
Change Setpoints
Use to enter the Head Pressure Control PID variables
below. Pressing this key places a green box around the
first changeable setpoint. Use the up/down, left/right
arrows to place the selection box around the desired
setpoint. With the setpoint selected, press the ENTER
() key. A dialog box appears with the range of set-
tings. Using the NUMERIC keys, enter desired value.
Then, press the ENTER () key.
Head Pressure Control – P
Sets the Proportional Gain of the Head Pressure Con-
trol (0.00 to 5.00; default 2.00). Use the CHANGE
SETPOINTS key as described above to select/enter
this setpoint.
Head Pressure Control – I
Sets the Integral Gain of the Head Pressure Con-
trol (0.00 to 5.00; default 2.00). Use the CHANGE
SETPOINTS key as described above to select/enter
this setpoint.
Head Pressure Control – D
Sets the Derivative Gain of the Head Pressure Con-
trol (0.00 to 5.00; default 0.00). Use the CHANGE
SETPOINTS key as described above to select/enter
this setpoint.
NAVIGATION
Home
Returns user to HOME Screen.
Condenser
Returns user to CONDENSER Screen.
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