Temperature relay to protect transformers against excess temperature and to control a fan.
The temperatures in the windings are monitored with three Pt 100 sensors. The core temperature can be monitored with a fourth sensor.
The 4 alarms/output relays are used to control the fan, to signal an advance warning and to switch-off the transformer. Various programs facilitate using the alarm ideally for each application. Depending on the program, e.g. an extra relay is available for the fault message or for triggering due to exceeding the maximum core temperature.