Emerson Vilter Vission 20/20, Руководство по эксплуатации и обслуживанию

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8 – 3
Section 8 • Timers
Vission 20/20 • Operation and Service Manual • Emerson • 35391SC 2.7
Accumulative Anti-Recycle Timer:
•
This timer forces a specified time between compres -
sor starts. When the compressor starts, the timer
resets and starts timing and accumulates running
time. Once the compressor shuts down, it will not
be allowed to restart for the remainder of time left
on the Accumulative Anti-Recycle Timer. Unlike the
True Anti-Recycle Timer, if the compressor has run
for a time period that exceeds the setpoint of the
Accumulative Anti-Recycle Timer, then when the
compressor shuts down, it will be allowed to restart
immediately.
Compressor Interlock Bypass:
• Once the Vission 20/20 has sent a command to the
compressor starter to start, a return signal is expect-
ed. This timer defines how much time to wait for that
signal before setting a trip condition.
High Motor Amps Safety Bypass:
• Starting motors can typically pull much more than
its rates full load amps for a short time. This timer ig-
nores that sudden inrush of current for the specified
time.
Emergency Stop Timer:
•
Defines the amount of time the compressor is in a
False start condition before activating the Emergency
stop. The emergency stop output can be connected
to a shunt-trip in the case of a run away compressor
to remove all power to the system.
Low Suction Pressure Safety Bypass:
• Sets the time that the compressor is allowed to run at
lower suction pressure than would usually be allowed
at start-up.
High Superheat Temp Safety Changeover:
• This timer activates at shutdown and changes the re-
start parameters if the time has not been met.
Low Pressure Ratio Bypass:
• This timer bypasses the Low Run Pressure Ratio set-
points when compressor is running. After the timer
expires, the Cool Compression Low Run Pressure
Ratio safety is active.
Figure 8-2. Timers Screen - Page 2 (Cool Compression)