30
GOSSEN METRAWATT GMBH
Heating Current Monitoring
Function
Heating current is acquired with an external transformer (e.g. GTZ 4121).
An alarm is triggered if the current setpoint is fallen short of by more than 20% with
activated heat (control output I active), or if current is not “off” when the heat is switched
off. The alarm is not triggered until heating current is high enough when output I is active,
or when current drops to zero when output I is inactive.
Monitoring is inactive if the controller is switched to
oFF
, as well as in the case of step-
action controllers.
AMPS
current
setpoint
Heater phase nominal current is entered for this parameter.
AMPS
can be set to
Auto
for
automatic adjustment with the heater switched on. The currently measured value is
saved to memory.
Heating Circuit Monitoring
Function
– Can be set to active or inactive with the “Alarm 1” configuration digit (see
– Without external transformer, without additional parameters
– Requires correct optimization of
tu
and
Pb 1
control parameters,
i.e. heating circuit monitoring must be activated before self-tuning is started.
In the event of manual optimization or subsequent adaptation of control parameters,
the lower limit value for the
tu
parameter must be observed:
Pb 1
MRS
minimum
tu
=
•
50%
∆ϑ
⁄
Dt
∆ϑ
⁄
Dt = maximum temperature rise during actuation
– Error message
LE
appears after approximately 2 times
tu
, if heat remains on at 100%
and measured temperature rise is too small.
– Monitoring is not active:
where controller sort = limit transducer, actuator or step-action controller
during self-tuning
with standard signal input (R2100 C30, C31)
where PWR limiting
YH
< 20%
