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Notes:
1. The Heater burnout option is available on the CN4520, CN4620,
CN4720 controllers only.
2. The Heater burnout option cannot be used on the controller with a
4-20mA DC output. The current sensing transformer would pick up
current changes due to fluctuating power output, between 0% and
100%, which would result in a heater burnout alarm condition even
though no such condition existed.
3. The Cycle Time must be set at 6 secs. or higher in order for the
controller to correctly analyze the signal sent by the current sensing
transformer.
4. The power supply used should be the same for the controller and
heater to eliminate current fluctuations due to power differences
between different power supplies.
Wiring and Setting:
1. Choose the correct current sensing transformer based on the maxi-
mum current usage of the heater.
0 - 30 Amps (Part # CN4H30)
20 - 50 Amps (Part # CN4H50)
2. Thread the hot lead going to the
heater through the “donut” of
the current sensing transformer.
Connect the wires of the current sensing transformer to the current
sensing transformer input terminals on the back of the controller.
Connection to controller
(Polarity not important)
Hot lead to Heater