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13–11–602 Page 56
CONTROLS TROUBLE SHOOTING GUIDE (Continued)
Message
Action Needed
Display indicates
If the display indicates “SHUTDOWN”, refer to the shutdown trouble–
“SHUTDOWN”
shooting section for assistance. In addition to the messages shown, there
are several internal and system diagnostics performed by the controller.
Consult the factory for additional assistance.
Compressor runs,
In the CONSTANT RUN and LOW DEMAND modes, the compressor will
but does not load
not load until the pressure drops below reset pressure. Refer to the oper-
ating instructions for further information. If pressure is below the reset
pressure, check that the inlet valve operates freely. Check that the IVO
and IVC valves are wired and operating properly.
Compressor runs,
If the inlet valve closes at low pressure, check the wiring to the blowdown
unloads at low pressure
valve and the piping and check valves in its discharge line.
Compressor does
The ES controller operates the inlet valve to maintain pressure near the
not modulate
set pressure, matching delivery to demand. If the pressure continues to
rise above set pressure, check that the inlet valve operates freely, and that
control air is supplied to the IVC valve. If modulation does not close the
valve, it will be closed during a blowdown as pressure approaches the high
pressure limit.
Compressor cycles
The external air receiver should be sized appropriately to prevent rapid
rapidly between load
cycles. The rapid response time in the CONSTANT RUN mode will oper-
and unload
ate with small receivers, but any plant air system will operate more effi-
ciently with adequately sized storage. Refer to the operating instructions
for further information.
Display is illegible
Extra segments or “ghosting” of characters indicate damage probably
from excessive high voltage. Replace the controller, and install protection
to prevent further damage to electrical equipment.
Erratic pressures
The sequencing system transmits low–level signal between units to com–
in SEQUENCE only
municate pressures. Units must be properly grounded to a good ground
system, the communications cable should use only appropriate quality
cable, and the cable should be run in its own conduit.
Compressor cycles
In the sequence mode, the operating system requires all compressors be
rapidly in SEQUENCE
piped directly to receiver, such that all transducers sense the same pres-
mode only
sure. Check valves or restrictions between compressors and the storage
will cause system instability. Run units in AUTOMATIC mode until the sys-
tem is corrected.
LOW WATER
If this shutdown occurs in the sequence mode only, it indicates instability
PRESSURE in
due to rapid changes in pressure of the system. Remove restrictions be-
SEQUENCE mode only
tween the compressors and receiver, increase receiver size if necessary
to slow down the pressure swings.
Pressure display
Accuracy of the pressure display and controls requires that the controller
error
and transducers be calibrated together. This MUST be done with no pres-
sure at the transducer, or errors will occur. This is easiest to check with
all pressure removed. All pressure displays should indicate 0 psi (o bar)
+1psi. If the display indicates greater pressures, recalibrate the system
as instructed in the configuration adjustments. Note: reservoir pressure
may drop below zero psig when the compressor is stopped, but will return
slowly to zero as the vacuum is relieved.
Summary of Contents for TWISTAIR EWDQ D
Page 14: ...13 11 602 Page 4 FIGURE 1 6 AIR WATER SCHEMATIC FIGURE 1 7 OIL SCHEMATIC...
Page 17: ...13 11 602 Page 7 DECALS 206EAQ077 212EAQ077 218EAQ077 211EAQ077 207EAQ077...
Page 18: ...13 11 602 Page 8 DECALS 216EAQ077 206EWD077 222EAQ077 221EAQ077 208EAQ077...
Page 35: ...13 11 602 Page 25 FIGURE 4 2 FLOW CHART FOR SET UP PROGRAMMING...
Page 44: ...13 11 602 Page 34 FIGURE 4 6 CONTROL TUBING SCHEMATIC 206EWD797 A Ref Drawing...
Page 48: ...13 11 602 Page 38 FIGURE 4 10 WIRING DIAGRAM FULL VOLTAGE 202EWD546 REF DRAWING...
Page 49: ...13 11 602 Page 39 FIGURE 4 11 WIRING DIAGRAM WYE DELTA 203EWD546 REF DRAWING...
Page 50: ...13 11 602 Page 40 FIGURE 4 12 AUTO SENTRY ES CONTROLLER DISPLAY...
Page 53: ...13 11 602 Page 43 FIGURE 5 2 FLOW DIAGRAM AIR COOLED 202EWD797 B Ref Drawing...
Page 54: ...13 11 602 Page 44 FIGURE 5 3 FLOW DIAGRAM WATER COOLED 203EWD797 A Ref Drawing...
Page 68: ......