Surge Protection Screen (Single-Compressor Operation); Figure 21 - Surge Protection Screen (Single Compressor Operation) - York YD Series Operation Manual

SECTION 2 – OPTIVIEW CONTROL CENTER
Overview
This screen displays the single-compressor surge pro-
tection parameters. The setpoints applicable to this
feature are maintained here. An LED illuminates when
a surge event is detected during single-compressor op-
eration.
This screen and all parameters displayed
here apply to single-compressor opera-
tion only
Display Only
Delta P/P
A parameter that represents the system differential or
"Head pressure". It is calculated as (condenser pres-
sure – evaporator pressure) / evaporator pressure.

FIGURE 21 - SURGE PROTECTION SCREEN (SINGLE COMPRESSOR OPERATION)

64
SURGE PROTECTION SCREEN
(SINGLE-COMPRESSOR OPERATION)
Surge Window Time
When the chiller enters run mode, this value counts
up to the time programmed as the COUNT WINDOW
setpoint. When it reaches the COUNT WINDOW min-
utes, the number of surge events in the oldest minute is
discarded and the number of surge events in the most
recent minute is added, thus providing a rolling count
of the total surge events that have occurred in the last
COUNT WINDOW minutes. This value is reset when
the chiller shuts down.
Surge Window Count
Displays the number of surge events that have oc-
curred in the last 1 to 5 minutes as programmed with
the COUNT WINDOW setpoint. If the chiller has been
running for less than the COUNT WINDOW minutes,
it is the number of surge events that have occurred
within the last number of minutes displayed as the
SURGE WINDOW TIME. The count is cleared when
the chiller shuts down.
FORM 160.69-O1
ISSUE DATE: 9/30/2012
LD08618
JOHNSON CONTROLS