TC 816 Operation Manual
THERMON…The Heat Tracing Specialists
®
Page 38 of 42
Operation Manual 0503 E TC 816
4.3.6
Parameter P21:
D HEAT
This Parameter is:
•
Valid for Temperature Controller Zones
- Zones 1 through 16
- unit in: 0,1 x s (seconds) => value of 10 means 1 s
•
Not
valid for
Limiter Zones
•
Not valid for
Current Zones
Control mode set to PID control, see chapter 4.3.3.
With parameter P21 the differential time (
D HEAT
) is set in
1/10
s (seconds). This portion of the control
algorithm ‘brakes’ the control output for a time which can be set here, in the event of the actual value ap-
proaching the reference value at too high speed.
Adjustment thresholds: 0...999
Default value:
200
Note:
With
D HEAT
set to
“0” the differential portion of the PID control is switched off.
4.3.7
Parameter P22:
APC MIN T
This Parameter is:
•
Valid for Temperature Controller Zones
- Zones 1 through 16
- unit in: °C or °F
•
Not
valid for
Limiter Zones
•
Not
valid for
Current Zones
Control mode set to APC control, see chapter 4.3.3.
Parameter P22 determines the lowest ambient temperature (
APC MIN T
) for which the heat tracing
circuit is designed.
Adjustment thresholds: -40...+5
Default value:
-20
4.3.8
Parameter P23: Spare
This Parameter has no function, it is a spare parameter to give the possibility of future functional expansion of
the TC 816 heat tracing temperature controller.
