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Ø 5/16
4
4 1/2
6 9/16
4 1/2
8
203
MAX
Ø 1/16
4
1 7/32
3/8
F
50
0
C
50
100
C
F
2
2
8
114
167
114
102
13
102
30
10
51
25
SW ITC H NUMBER
MEDIA TE
ADJUSTABLE RA NGE
C LAS S I
G RO UPS: B, C & D
C LAS S II
G RO UPS: E, F & G
C LAS S III
R
TYPE 4
LISTED
366S
TEMPERATURE SWITCH
FM
APPROVED
ELECTRICA L RATING S
THERMO S TAT F OR
H AZA RDO US LOC ATIO NS.
II 2 G D
00 81
EEx d IIC T6
LCIE 02 ATEX 6 206
Tamb -40 %%dC
ELECTRICA L RATING S
REMOTE BULB AND
CAPILLARY MODEL
LOCAL MOUNT MODEL
1 HEX
1/2
(INTERNAL)
HEX
INTERNAL
GROUND SCREW
WITH CLAMP
ADJUSTING KNOB
REMOVE COVER
TO ADJUST
TIGHTEN 4mm SET SCREW
TO LOCK COVER IN PLACE
AFTER FIELD WIRING
EXTERNAL
GROUND
SCREW
WITH
CLAMP
4
102
3/4 NPT
FEMALE
CONDUIT
TERMINAL BLOCK
ACCEPTS #16-#10 AWG
LEAD WIRES
6 FOR RELAY MODEL ONLY
152
Ø 9/32 MOUNTING HOLE 4 PLACES
7
For service or ordering information
Consult factory or authorized factory representative.
Specify full catalog number (with any optional modifica-
tions or factory set-point) as shown on part
number code.
TA7140
15 TO 140 °F (-9 TO 60 °C)
-40 TO 160 °F (-40 TO 71 °C)
SWITCH
NUMBER
BULB SENSOR EXPOSURE
LIMITS (PROOF)
ADJUSTABLE RANGE
TEMPERATURE RANGE
TH7325
25 TO 325 °F (-4 TO 163 °C) -40 TO 420 °F (-40 TO 215 °C)
Warranty
All products of the company are sold and all services
are offered subject to the company's standard condi-
tions of sale.
Causes of improper operation:
1. Incorrect electrical connection: check leads to
switch. Be sure they are properly connected.
See “Wiring” section for circuitry color code.
2. Faulty control circuit: check electrical power
supply to switch. Check for loose or blown fuses,
open-circuited or grounded wires, loose connections
at switch.
3. Incorrect temperature: check temperature in
system. Temperature must be within range
specified on nameplate.
4. Excessive vibration: check for temperature
fluctuations in system. Check swi tch mounting
and be sure there is no excessive vibration.
DIMENSIONS IN BOXES
ARE IN MILLIMETERS
NELSON HEAT TRACING SYSTEMS, Tulsa, OK 74146
Bulletin No. 27278-AD 3-10-08 2 of 3
TH7325-2
25 TO 325 °F (-4 TO 163 °C) -40 TO 420 °F (-40 TO 215 °C)
Troubleshooting
Warning:
Disconnect electrical power supply to
swi tch before removal or inspection.
Failure to observe this warning could
result in serious injury or switch damage.
Important:
The swi tch is not field-repairable. In
case of damage, replace entire swi tch.
If the operation of the switch cannot be corrected
by the above means, consult factory or authorized
factory representative.