Johnson Controls York YKEP Series User Manual

FORM 160.77-O2
ISSUE DATE: 11/15/2011
JOHNSON CONTROLS
72
SECTION 3 - YKEP CONTROL PANEL OPERATION
VPD1
Condenser - Evaporator pressure at the highest design
condition.
VPD2
Condenser - Evaporator pressure at a low head condition.
MVP1
Minimum PRV position to avoid surge at the pressure
differential defined by VPD1.
MVP2
Minimum PRV position to avoid surge at the pressure
differential defined by VPD2.
Min Vane Calc
Min Vane Calc displays the minimum PRV position
determined by the map for the current differential pres-
sure condition. When a surge is detected, the PRV po-
sition and differential pressure at the time of the event
are plotted on the map to adjust the line.
OVERVIEW
This Screen provides access to the Primary compressor
anti-surge control threshold setpoints. It consists of a
Pre-rotation vane (PRV) control section and an option-
al speed control section for compressors employing a
Variable Speed Drive.
VANE ANTI-SURGE MAP
The vane anti-surge map defines the minimum PRV
position permitted for surge-free compressor opera-
tion as a function of differential pressure between the
condenser and evaporator. The map defines a line in
terms of PRV position on the horizontal axis and shell
pressure differential on the vertical axis. Primary com-
pressor operation is only permitted to the right side of
this line by restricting PRV closure to no further closed
than the position defined by this line for each existing
pressure differential condition prevailing. The line is
defined by the following points:
PRIMARY ANTI-SURGE SCREEN
LD15966
FIGURE 38 - PRIMARY ANTI-SURGE SCREEN

Johnson Controls York YKEP Series Specifications

General

Brand	Johnson Controls
Model	York YKEP Series
Category	Chiller
Language	English