With up to six sensors, the TR640IP and TR660IP temperature relays from Ziehl Industrie-Elektronik monitor temperatures on transformers, motors or in other applications for up to seven limit values. In addition to Pt 100 and Pt 1000, PTC thermistors can also be connected. A new feature is the monitoring of the rate at which the temperature rises - in the event of rapid heating, the device switches off before limit values are exceeded, thus preventing overheating. The recording of temperature statistics allows conclusions to be drawn about the long-term load. The integrated option 2 from X ensures that an alarm is only triggered if the limit value has been exceeded in at least two sensors. This increases protection against false alarms. The suffix 'IP' in the device designation stands for the Ethernet interface, which is provided as standard and offers an intuitive web interface for parameterization and visualization as well as a Modbus TCP interface. This allows the devices to be integrated into higher-level systems. The color LC display clearly shows all measured values. Parameters can be set on the device using a joystick.