60-2159—8
4
C645A-E PRESSURE SWITCHES
5
(127)
3-5/8
(92)
1-13/16
(46)
5/16
(7.9)
1
(25.4)
3/4
(19)
2-1/4
(57.1)
2-3/4
(69.8)
1-1/4
(31.7)
2-5/8
(66.7)
3/4
(19)
3
(76.2)
3-7/8
(98.4)
7-7/8 DIA. (200)
9/32 (7.1)
DIA. (2)
3/16 (4.8)
DIA.
1/8-27 INCH NPT
MANUAL
RESET
LEVER
1
1
IMPORTANT: FOR MODELS WITH LOCKOUT, DO NOT OBSTRUCT MANUAL RESET LEVER.
M7563
1-1/8
(29)
MOUNTING BRACKET
(OPTIONAL)
1/4-18 INCH
NPT
Fig. 2. Dimensions of C645C in in. (mm).
INSTALLATION
When Installing this Product . . .
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Read these instructions carefully. Failure to follow them
could damage the product or cause a hazardous
condition.
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Check the ratings given in the instructions and on the
product to make sure the product is suitable for your
application.
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Installer must be a trained, experienced service
technician.
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After installation is complete, check out product
operation as provided in these instructions.
CAUTION
Disconnect power supply before beginning installation
to prevent electrical shock or equipment damage.
Mounting
The C645 has a hexagonal fitting with a 1/4 in. NPT tapping,
which is the high pressure connection in differential
applications. The bleed fitting is 1/8 in. NPT female tapped. In
differential pressure control applications using air, connect the
lower pressure to the bleed fitting (Fig. 3 and 4). In
applications using combustible gases, vent the bleed tapping
according to applicable standard code or jurisdictional
authority.
The C645A,B,D can be mounted in any position but are more
accurate when mounted horizontally. The C645C is mounted
with the diaphragm vertical and the bleed fitting at the bottom.
