4
It is not necessary to remove the control chassis from the housing for
installation. If the control chassis is removed from the housing, you
must follow industry standard practice for control and protection
against Electro-Static Discharge (ESD). Failure to exercise good ESD
practices may cause damage to the control.
Wiring to housing terminals while chassis is removed may cause dis-
tortion of the internal connector and possible damage to the connec-
tor when the chassis is reinstalled. It is strongly recommended that
the control housing be wired with the chassis installed.
INSTALLATION
Mount the instrument in a location that will not be subject to excessive temperature,
shock or vibration. All models are designed for mounting in an enclosed panel.
Select the position desired for the instrument on the panel. Prepare the panel by cut-
ting and deburring the required opening.
From the front of the panel, slide the instrument through the cut out. The housing
gasket should be against the housing flange before installing.
From the rear of the panel slide the mounting collar over the housing. Hold the hous-
ing with one hand and using the other hand, push the collar evenly against the panel
until the springs are compressed. The ratchets will hold the mounting collar and
housing in place.
C
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_
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+
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SHIELD
SHIELD
SHIELD
SHIELD
TIE SHIELD TO EARTH GROUND
TIE SHIELD TO EARTH GROUND
TO RS232 TO
RS485 CONVERTER
TO RS232 TO
RS485 CONVERTER
120 OHM
RESISTOR
120 OHM
RESISTOR
LAST UNIT ON RS485 BUSS
LAST UNIT ON RS485 BUSS
WIRE NUT
WIRE NUT
- RS485 WIRING TO DAISY CHAIN INSTRUMENTS ON THE RS485 BUSS
UP TO 128 UNITS MAY BE DAISY CHAINED
THE 120 OHM RESISTOR
IS USUALLY ONLY
NECESSARY FOR LONG
WIRE RUNS.
THE 120 OHM RESISTOR
IS USUALLY ONLY
NECESSARY FOR LONG
WIRE RUNS.
DIGIHELIC
®
CONTROLER RS485 WIRING
B-32:B-32 7/9/09 2:52 PM Page 5
www.calcert.com
1.888.610.7664
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