7 – 1
Vission 20/20 • Operation and Service Manual •Vilter/Emerson • 35391SC 1.8.5153
Overview
The Alarms and Trips screen allows the operator to view
and adjust settings for compressor safety and alarm set-
tings, see Figure 7-1. Alarms and Trips Screen. Vission
20/20 uses Alarms as a way to notify the operator of
running parameters that if left unchecked could result
in the compressor shutting down due to a trip. Trips are
the conditions that exceed the safety limits of the com-
pressor or refrigeration system and stops the compres-
sor. Trips are always displayed as a red banner and alarms
are yellow banners on the top and bottoms status bars.
Alarms and trip conditions are also logged to provide
an operational history for the operator. Both alarms
and trips will be logged in the event list accessible from
the menu screen. Trips also trigger the input/output
screen to take a snapshot of all input and output values
as freeze screen. The freeze screens are available as left
side tabs in the input/output screens and are very useful
as a troubleshooting tool for the operator.
Alarms and Trips Setpoints
Low Suction Pressure (Alarm & Trip):
• This is the low suction pressure safety. This safety
is active in both temperature and pressure control
modes. An alarm or trip will be activated if the suc-
tion pressure falls below the setpoint values.
High Discharge Pressure (Alarm & Trip):
• This is the high discharge pressure safety. The alarm
or trip will be activated if the discharge pressure rises
above the setpoint value.
High Process Temperature (Alarm only)
• This alarm is active when the process temperature
is at or above the setpoint value. There is no trip
setpoint.
Low Process Temperature (Alarm & Trip):
• This is the low control temperature safety. This safety
is active when process temperature control has been
Figure 7-1. Alarms and Trips Screen
Section 7 • Alarms and Trips