Alarm Signals; Automatic Restart - Powerex SE Serie Mode D'emploi

10HP - 20HP Scroll Enclosure Air Compressors
OPERATION Cont'd

ALARM SIGNALS

The PLC control for the scroll enclosure compressor will
display the ALARM screen and activate the GENERAL
FAULT indicator on the alarm screen display if either of the
two conditions occurs:
1. High temperature at the sensor located at the after cooler
inlet. Each compressor module has its own sensor. A high
temperature condition will result in the power to that motor
being shut off. The GENERAL FAULT alarm display will
stay on and the circuit will stay off even after the sensor
cools, and can only be restored when the alarm is cleared by a
user. If a high temperature condition occurs, the reason
should be determined and corrected before restarting the
circuit as un-repairable damage to the scroll pump may result
from operation with repeated high temperature alarms.
2. Motor Overload, if the current to the motor exceeds the
setting of the adjustable motor protector, the contactor
associated with that motor is de-energized, and that motor
will not run. The alarm display and condition is maintained
until the alarm is cleared and the motor protector reset. The
circuit will be restarted as needed. If a motor overload occurs,
the root cause should be determined and corrected or motor
damage may result.
The user can activate the acknowledge function (button
labeled ACKN) to allow the display to go back to SYSTEM
STATUS or any other screen. Touch the VIEW button to
advance to a screen showing which pump-motor assembly is
in fault and for what reason. The fault will display and the
affected pump-motor will be disabled until the RESET button
is pushed.
The PUMP MAINT indicator will activate when the running
hours of any pump accumulates to a required maintenance
interval. Use ACKN to allow the STATUS screen or other
screens to be displayed. Touch the VIEW button to advance
to the next screen. Consult the maintenance schedule and
scroll air compressor manual for details of what maintenance
needs to be performed. To reset the PUMP MAINT indicator
for an individual pump, open the PUMP INFO screen for that
pump, hit the TO RESET button, and use the keypad display
to enter the authorization code when prompted.
Motor Warning: The control also tracks how many times per
hour an individual motor is called on to start. If the starts per
hour exceed 17.5, there is an increased risk of motor damage.
The warning is displayed, but the system is not shut down.
The user can select a wider operating pressure differential to
reduce the starts per hour or install a larger air receiver. The
ACKN button, which will have to be pressed for each motor
in alert, allows the display to be shifted back to SYSTEM
STATUS or any other screen before the warning automati-
cally resets itself at the end of the hour. The RESET button
will not clear the warning.
ALARM LOG
A record of all alarm or warning events is kept in the alarm
log. Reset status is tracked as well. The alarm log is
maintained as long as the unit is powered and for up to three
days after power is removed from the control.
The following additional information is available by selecting
the SYSTEM TRENDS from the MAIN screen:
The control tracks the amount of time the pumps are in use
and compares that to the available time. The ratio is
displayed. The LOAD FACTOR is displayed for the most
recent 24 hour period.

AUTOMATIC RESTART

When power is applied to the Powerex scroll enclosure com-
pressor control, the display will illuminate and go to the SYS-
TEM STATUS screen. Settings will be retained from the last
time the system had power. The motors will not energize until
the ON button is pushed on the control switch below the dis-
play. (Only the JOG function will override the ON button). In
the event of a loss of power, the user must push the ON but-
ton to restore the compressors to operation. If automatic re-
start is desired, go to the SYSTEM SETUP screen PG2 and
select ENABLE AUTO RESTART. To disable, use the other
button.
Pg 11