Surge Protection Screen; Figure 20 - Surge Protection Screen - York YD Series Operation Manual

SECTION 2 – OPTIVIEW CONTROL CENTER
Overview
This screen displays both single compressor and dual
compressor surge protection parameters. An LED il-
luminates when a surge event is detected. Impeller
animation indicates when a compressor is running.
This screen also serves as a gateway to sub-screens for
viewing and programming of the single compressor
and dual compressor surge protection setpoints.
Display Only
Single Compressor Operation
Surge Window Time
When the lead compressor is started, this value counts
up from 1 minute to the time programmed as the
COUNT WINDOW Setpoint. When it reaches a count
equal to the COUNT WINDOW setpoint, it doesn't in-
crement anymore and the number of single-compressor
surge events in the oldest minute is discarded and the
number of single–compressor surge events in the most
recent minute are added, thus providing a rolling count
of the total single-compressor surge events that have
occurred within the last number of minutes displayed
as the SURGE WINDOW TIME. This value is reset
when one or both compressors have shutdown.

FIGURE 20 - SURGE PROTECTION SCREEN

62

SURGE PROTECTION SCREEN

Surge Window Count
Displays the number of single-compressor surge events
that have occurred in the last 1 to 5 minutes (as pro-
grammed with the COUNT WINDOW setpoint). If the
single-compressor has been running for less than the
COUNT WINDOW setpoint minutes, it is the number
of dual-compressor surge events that have occurred
within the last number of minutes displayed as the
SURGE WINDOW TIME. The count is cleared when
the one or both compressors have shutdown.
Total Surge Count
Displays the total number of single-compressor surge
events that have occurred over the lifetime of the chill-
er.
Surge Detected (LED)
Illuminates for 5 seconds each time a single-compres-
sor surge event is detected.
Delta P/P
A parameter that represents the system differential or
"Head Pressure". It is calculated as (condenser pres-
sure – evaporator pressure) / evaporator pressure.
FORM 160.69-O1
ISSUE DATE: 9/30/2012
50065
JOHNSON CONTROLS