Watlow Series 922 - Manual (Page 35)

How to Install and Wire, Chapter 4 35 WATLOW Series 922 User's Manual
WARNING: With
Watlow mercury
relays, load must
have a unity power
factor. For RESIS-
TIVE LOADS ONLY.
Figure 29 -
Series 922 System
Wiring Example.
Single Phase 120VAC Application
Wiring Example
WARNING:
Install High or low temperature limit control protection in systems where an
overtemperature or undertemperature fault condition could present a fire hazard
or other hazard. Failure to install temperature limit control protection where a
potential hazard exists could result in damage to equipment and property, and
injury to personnel.
L2
Integral Setpot
140A-16XX-6000
High Limit Control
L1
(-) (+)TC Input
L1
L1
L2
Dry Temp. RTD
Fuses
Mercury
Relay for
Control
Fuse
Load
Power
L2
High Limit
Control Power
120 VAC
Indicator ON when
limit trips
High Limit
Mechanical
Contactor
Limit Sensor
Wet Bulb
RTD Sensor
Coil
Oven
Load
Power
Normally Open
Momentary
Switch
L1
L2
Fuse
L1
L2
Earth Ground
120 VAC
Control
Power
Control Output
Wet Bulb RTD
Dry Temp.
RTD Sensor
Heater
Humidifier
Dehumidifier
L1
L1
L2
L2
L1
L2
Cooling Output
(internal to oven)