Wiring The Current Transformer; Heater Burnout Alarm Value - Omron E5AJ-A2HB Operation Manual

Heater Burnout Alarm Value

8-3

Wiring the Current Transformer

Heater
To the CT input terminals of the
E5jJ
8-4

Heater Burnout Alarm Value

Refer to the following diagram for the wiring the CT.
Relay driven with
control output
AC power supply
CT
To obtain the proper heater burnout alarm value, check the normal heater cur-
rent value and heater burnout current value with the heater current value display
on display level 1 first and set the heater burnout alarm value to the mean value
of these two values. If more than one heater is used, check the burnout value of
the heater with the smallest current consumption value.
Heater burnout
alarm value
If the difference between the normal heater current value and heater burnout
current value is comparatively small, heater burnout detection will not be stable.
For stable detection, the difference must be 1.0 A minimum if the heater current
consumption is less than 10.0 A and it must be 2.5 A minimum if the heater cur-
rent consumption is 10.0 A or more.
If normal current value t 10.0 A
Then normal current value – heat burnout current value w 1.0 A
If normal current value w 10.0 A
Then normal current value – heater burnout current value w 2.5 A
The heater burnout alarm value can be set within a range of 0.0 to 50.0 A. If the
alarm value is set to 0.0 A or 50.0 A, no heater burnout detection is possible. The
alarm output is always OFF if the alarm value is set to 0.0 A and always ON if the
alarm value is set to 50.0 A.
To the CT input terminals of the E5jJ.
The CT input terminals have no polarity.
Normal heater Heater burnout
+
current value current value
=
2
Section 8-4
To heater
CT
51