4 Basic Operation
4 - 64
E5@C-T Digital Temperature Controllers User’s Manual (H185)
4-12 Using Heater Burnout (HB) and
Heater Short (HS) Alarms (Not
Supported for Position-proportional
Models.)
These functions are supported for models that detect heater burnout (HB) and heater short (HS)
alarms.
z What Is an HB Alarm?
An HB alarm is detected by measuring the heater current with a current transformer (CT) when the
control output is ON. If the measured heater current is lower than the setting of the Heater Burnout
Detection parameter, an alarm is output.
This alarm cannot be used for the cooling control output. With the default settings, the HB alarm is
output on auxiliary output 1. You can use the output assignment parameters to change the output.
You can use an integrated alarm to output an OR of alarms 1 to 4 and the other alarms. For details
on the integrated alarm, refer to 5-8 OR Output of Alarms.
z Parameters
4-12-1 HB Alarm
Parameter No. 1 display Value No. 2 display Level
HB ON/OFF hbu OFF or ON (default: ON) off, on Advanced Function
Setting Level
Heater Burnout
Latch
hbl OFF or ON (default: OFF) off, on
Heater Burnout
Hysteresis
hbh 0.1 to 50.0 A (default: 0.1 A) 0.1 to 50.0
Heater Burnout
Detection 1 or 2
(alarm current)
hb1
hb2
0.0 to 50.0 A (default: 0.0 A) 0.0 to 50.0 Adjustment Level
Heater Current 1 or
2 Value Monitor
ct1
ct2
0.0 to 55.0 A 0.0 to 55.0
Auxiliary Output 1
to 4 Assignment
sub1 to sub4 HB: HB alarm or HA: Heater
alarm
hb or ha Advanced Function
Setting Level
Temperature sensor
E5@C-T
Temperature Input
SSR
Voltage output (for driving SSR)
CT
Current value
Auxiliary output
(assigned to an HB alarm)
×
Heater burnout