Gardner Denver TWISTAIR EWDQ D Скачать руководство пользователя

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no keys are pressed for 5 seconds, the display will re-
vert to its normal mode.

The display is also used as a service reminder for nor-
mal maintenance items. These include the change wa-
ter filter, change air filter, change oil filter, and change
oil messages, which are based on recommended ser-
vice intervals. The advisory messages also indicate
low or high temperature operation, if the unit has been
operated near its tolerable limits. When these condi-
tions are sensed, the yellow “ADVISORY” light will
come on, and the message will alternate with the nor-
mal lower line message. These messages are in-
tended to advise of conditions which may lead to a
shutdown.

Temperature advisories may be cleared while the unit
is running by simply pressing the ENTER key. To reset
the service advisories, press the STOP/RESET key to
stop operation of the compressor. After it has stopped,
disconnect power and service as required. After serv-
icing, restore power and reset the board as indicated in
the programming / maintenance section below.

PROTECTIVE SHUTDOWNS

The “AUTO SENTRY

–ES” will shut down the unit fol-

lowing any fault detected in the following devices.
Long–term problems will have a brief blowdown period
before fully shutting down. Following a shutdown, a
message will be displayed, with the top line indicating
“SHUTDOWN” and the lower line indicating the cause.
The shutdown light will be steadily lit if the cause still ex-
ists, or will flash if the cause has been cleared. To re-
sume operation, the cause of the shutdown must be
corrected and the controller reset by pressing the
“STOP/RESET” key.

Motor Protective Devices – Overload heaters are
furnished for the starter in the voltage range specified.
There are three (3) overloads in the starter of proper
size for the starter and its enclosure. Note that motor
nameplate current must be multiplied by 0.577 for wye–
delta starters. The display will indicate that an overload
relay has tripped. The overload relay is reset by press-
ing the button on the relay itself, then the controller may
be reset. Motor current (amps) and voltage must be
measured in the affected motor wiring to locate the
cause for high current. Proper starter coil and contact
action is also monitored and errors in operation will
cause a shutdown with the cause displayed as a start
error.

High Temperature – The compressor is protected
from high discharge temperature by a thermistor probe
located in the compressor discharge elbow. The
“AUTO SENTRY

–ES” will shut the compressor down

if temperature exceeds 190

F (88

C) (or lower per

user adjustment) or if rapid temperature rise is de-
tected. Oil injection temperature and final unit dis-

charge temperatures are also monitored, and will pro-
vide high temp shutdowns. Shutdown will also occur
if the temperature at any of these locations falls below
freezing. The location of the temperature fault will be
displayed. Thermistor probes are also checked for
open or shorted circuits, and the display will indicate the
location of the defective probe.

Machine damage will occur if com-
pressor is repeatedly restarted after
high temperature stops operation.
Find and correct the malfunction be-
fore resuming operation.

Water Filter Differential Pressure – The pressure
drop across the water filter is continually monitored by
the “AUTO SENTRY–ES”. The unit will be shut down
at a differential pressure of approximately 40 psig (2.8
bars). This becomes active only after the compressor
has been running and pressures have had time to stabi-
lize.

High Water Level – If the water management controls
are unable to maintain proper water levels, the com-
pressor will be shutdown to prevent damage. Check
wiring and piping of the drain solenoid. If wiring errors
are detected in the float switch, a shutdown will occur,
and the display will indicate a bad float switch.

High Pressure – The “AUTO SENTRY–ES” will first
attempt to unload and blow down the unit if excessive
pressures are detected in the reservoir or the plant sys-
tem. If unsuccessful, a shutdown will occur. Shut down
will also occur if a defective transducer is detected. The
display will indicate the location of the high sensed
pressure or transducer (xducer) error. Check that all
adjustments have been properly made, and all connec-
tions are secure.

Low Water Pressure – The “AUTO SENTRY–ES” will
shutdown the unit if inadequate water pressure is de-
tected after starting. If this occurs, check the wiring and
piping to the solenoid valves.

Low Oil Pressure – The “AUTO SENTRY–ES” moni-
tors oil pressure, and will shut down the unit if inade-
quate oil pressure is detected. If this occurs, check the
wiring and piping to the oil pump.

Emergency Stop – Pressing the emergency stop but-
ton will shut down the unit and the controller. To restart,
pull the button out to its normal position and reset the
controller. This should be used for emergency pur-
poses only – use the keypad “STOP/RESET” for nor-
mal controlled stopping.