Hysteresis
If the temperature were to fluctuate around the set limit value, it would be impossible to
prevent the fan repeatedly switching on and off without specifying the hysteresis.
Since this behaviour would degrade the effectiveness of the whole system, a hysteresis in
the range of a few Kelvin is recommended.
The hysteresis can be set in the range of 0...30 K.
Programming/Setup
of
the
control
inputs and
outputs
5.1.4
Both the REG-D
TM
and the REG-DA voltage regulators can receive various control signals as
binary signals and also output control signals via relay outputs.
The following Transformer Monitor specific input functions are available:
Buchholz alarm (indication signal)
Buchholz trip (indication signal)
Oil pump 1 in operation (indication signal)
Oil pump 2 in operation (indication signal)
The 'Buchholz Alarm' and 'Buchholz Trigger' signals must be supplied to the controller by a
separate Buchholz relay and can then be transmitted to a higher-level control system
through a corresponding SCADA.
The following Transformer Monitor specific output functions are available:
The output functions are available for relays, as well as for LEDs.
Oil temperature transformer alarm
Winding temperature alarm
Heater on (control signal)
Cooling group 1 on (control signal)
Cooling group 2 on (control signal)
Cooling group 3 on (control signal)
Cooling group 4 on (control signal)
Cooling group 5 on (control signal)
Cooling group 6 on (control signal)
Oil temperature tap changer alarm
Oil level in the tap changer to low
Oil level in the tap changer to high
Oil level in the transformer to low
Oil level in the transformer to high