13–11–602 Page 30
CONNECTION TO EXTERNAL CONTROLS
The ES controller offers interconnection points for ex-
ternal controls and indicators. This allows simple con-
nection to remote controls and indicators, or integration
into any plantwide controls system.
Remote On / Off – Remote on–off control of the sys-
tem requires only a simple two–wire control, with an
isolated contact suitable for 120 volts, 1 amp. This may
be a switch, a timer contact, a relay contact, or a PLC
output. To connect, simply run the two wires to the con-
trol enclosure, remove the jumper between terminal 6
and terminal 9 on the terminal strip, and connect the
two wires to terminal 6 and terminal 9.
The air compressor will operate normally in its selected
mode whenever this contact is closed (turned on).
Note that the keypad is always the master control; the
operating mode must be selected at the keypad, and
the remote is not capable of starting a unit after the
STOP/RESET key has been pressed to place the con-
troller in the READY state. When the contact is opened
(turned off), operation depends on how the controller
has been programmed and what it is doing prior to
opening the contact.
If the compressor was already stopped in automatic or
sequence modes, it will remain stopped and will not re-
start until the contact is closed. The display will flash
the message “REMOTE STOP” to indicate that it is
waiting for the remote signal.
If the compressor was running in any mode when the
contact was opened, and the remote response is pro-
grammed for “IMMEDIATE”, the compressor will im-
mediately unload and blowdown. After completion of
blowdown, the motors will stop, and the unit will be in
the “REMOTE STOP” mode as indicated above.
If the compressor was running in any mode when the
contact was opened, and the remote response is pro-
grammed for “TIMED UNLOAD”, the compressor will
immediately unload and blowdown. It will then continue
to run unloaded for whatever period has been pro-
grammed for “AUTO TIME” (or will complete the re-
maining auto time if already blown down). After
completion, the motors will stop, and the unit will be in
the “REMOTE STOP” mode as indicated above. This
is the preferred setting for automatic remote controls
which may cycle in less than 1/2 hour, as the motor is
always cooled evenly and rapid start cycles are pre-
vented.
Alarm Relay – The ES controller is provided with an
alarm relay which may be connected to a remote
mounted indicator light, horn, or into a PLC input of a
plantwide control system. The contact is commercial
rated 2 amps at 120 volts. The relay is turned on when-
ever there is a shutdown condition requiring service at
the compressor, and remains off during normal opera-
tion, stopping, or power off conditions. The external
connections from the controller are from an isolated
form C (single–pole, double–throw) contact. This al-
lows control of either a “compressor okay” or a “com-
pressor shutdown” remote indicator.
To use this relay, connect the supply wire for the remote
circuit to terminal 33 (relay common) on the terminal
strip. Connect a wire to the indicator from either termi-
nal 31 (normally open) or from terminal 32 (normally
closed). Connect the other side of the indicator to its
neutral.
Serial Communications
If units are NOT connected in sequence, the serial port
is available for communications of compressor data to
external monitoring systems. Data available include all
pressures and temperatures, and a report of internal
service data. This is accessible with a PC or PLC with
an RS–485 communications port. For protocol in-
formation, request drawing 200EAP1255.
OTHER CONTROL DEVICES
In addition to the electronic controller noted above, the
following components are also used to control opera-
tion of the compressor unit.
Relief Valve (FIGURE 1–2, page 2) – A pressure relief
valve(s) is (are) installed in the final discharge line and
set to approximately 120–125% of the unit’s full load
operating pressure for protection against over pres-
sure. Periodic checks should be made to ensure its
(their) operation.
The relief valve should be tested for proper operation
at least once every year. To test the relief valve, raise
the system operating pressure to 75% of the relief valve
set pressure and manually open the valve with the hand
lever. Hold the valve open for a few seconds and allow
it to snap shut.
When the relief valve opens, a stream
of high velocity air is released, result-
ing in a high noise level and possible
discharge of accumulated dirt or oth-
er debris. Always wear eye and ear
protection and stand clear of the dis-
charge port when testing the relief
valve to prevent injury.
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: ......
