Powerex SE Serie Mode D'emploi page 10

OPERATION Cont'd
OPERATING PANEL & SETTINGS
The Scroll Enclosure Air Compressor is controlled by a PLC
programmed at the Powerex factory. The operating status is
displayed on the HMI– touch screen panel on the front of the
compressor unit. The touch screen allows the user to select
operating parameters within predetermined limits set at the
factory. The touch screen also allows the user to change the
display to get more information about the operation of the
individual compressor modules and to take action based on
alarms and warnings. This enclosed scroll system utilizes a
PLC for alternation and will change the pump sequence
(Lead, Lag1, Lag2 etc) after every start or after 10-minutes,
which ever happens first. The HMI offers a MIN and MAX
system setpoint and three calculated pressure differential
settings. (Standard, Min and Max)
The factory default settings for HIGH and LOW Operating
Pressures are:
Standard Models
High Pressure Models
Differential setting default is STANDARD
Limits to difference between HIGH and LOW setpoints:
Maximum Differential
Minimum Differential
The control automatically divides the range between HIGH
and LOW Operating Pressure into equal operating intervals.
The differential for the operating intervals may be adjusted by
selecting STANDARD, MIN or MAX on the set up screen.
In STANDARD, the differential will be automatically set to
have a slight overlap between the individual pump intervals.
Each interval will be 135% of the possible minimum value.
In MIN, the differential will be automatically set to divide the
available range into equal intervals with no overlap. The
selection will result in the most frequent starting of the
electric motors for a given Operating Pressure range.
NOTE: more frequent motor starting can lead to reduced
motor life. Exceeding 17.5 starts per hour will cause a
warning display.
In MAX, the differential will be automatically set to increase
the overlap as compared to the Standard setting. Each interval
will be 235% of the possible minimum interval. Select this
mode to minimize the frequency of motor starts. Motor start
frequency can be reduced by using larger air receiver tanks,
selecting a wider range between HIGH and LOW Operating
Pg 10
10HP - 20HP Scroll Enclosure Air Compressors
Pressure and by selecting the widest differential.
To minimize power consumption, select the lowest possible
HIGH operating pressure and the smallest differential that
avoids exceeding the motor start frequency limit.
PERFORMING PRESSURE ADJUSTMENTS
The above display is the SYSTEM STATUS screen. (For
SED and SET models, only two and three sets of buttons/
indicators will be shown).
To adjust pressure settings, touch the SELECT SETPOINT
button. The screen will change to this display:
90-116 PSIG
119-145 PSIG
Touch the screen at either the HIGH SET or LOW SET
50 PSIG
button/indicator. A key pad display will be shown. Enter the
16 PSIG
desired pressure setting using the key pad and touch ENT.
CLR is clear, use it to backspace one digit.
CAN or Cancel, voids the whole input, use it to start over.
Pressure settings must be entered as whole numbers, no
decimal or factions. The individual intervals will be
calculated and shown in the display boxes on the right side of
the setting screen. If number are entered that are out of the
allowed range, the input will be scaled back to the range
limit.