Description

The digital temperature limiter DTL III Ex is designed for trace heating applications and is used for temperature monitoring of heating systems or heating circuits. The device is installed in the non-hazardous area. The heating or heating circuits can be installed both in media-protected and also in hazardous areas. Thanks to their integrated power supply unit with wide-range voltage, the devices can be used almost everywhere in the world.

Function

If the temperature at the Pt100 exceeds the set limit value, the DTL III Ex permanently interrupts the normally open 16 A switch contact. This situation is detected by a volt-free alarm contact (change-over contact) and passes on the signal to the control panel. After a temperature drop of 5 K below the limit set point, or after a fault has been remedied, the limiter can be re-activated by means of a re-set button on the device itself or via a remote re-set control. The DTL will also interrupt the switch contact in the event of a sensor open or short circuit. Process reliability is increased by additional monitoring functions such as pre-alarm, measuring circuit monitoring for sensor break, interruption and short-circuit as well as undershooting/overshooting of the measuring range. A multi-stage password management is available for effective parameter protection. When doing service work on the heating circuit, the load output can be turned off by means of a digital input and the temperature alarms can be disabled. Through the programming interface, the device parameters can be transferred to other devices by using a special programming key.