Figure 13 - Surge Screen - York YMC2 Operation And Maintenance

FORM 160.84-OM1
ISSUE DATE: 9/21/2017

FIGURE 13 - SURGE SCREEN

OVERVIEW
This screen displays the chiller compressor and all pa-
rameters relating to the Surge Protection feature. All
setpoints relating to this screen are maintained on this
screen.
The Surge Protection feature allows the user to define
how many surges are excessive and how the control
will react to an excess surge condition. When excess
surging is detected, it can be configured to shutdown
the chiller. The sensitivity of this surge detection is set
by the Sensitivity Setpoint on this screen.
DISPLAY ONLY
Delta P/P
A parameter that represents the system differential
or HEAD PRESSURE. It is calculated as (condenser
pressure – evaporator pressure) / evaporator pressure.
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
JOHNSON CONTROLS
SECTION 3 - OPTIVIEW™ CONTROL CENTER FUNCTIONS AND NAVIGATION
SURGE SCREEN
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.
Surge Detected (LED)
Illuminates momentarily when a surge is detected by
the Surge Protection feature.
Surge Count
This is the total number of surges accumulated by the
Surge Protection feature.
LD17927a
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