Overload protection
![]() | Technical data Please note the information in the technical data regarding load type, max. output current and short circuit current. |
When switching on lamp loads, high starting currents occur that are limited by the output circuit of the terminals (see fig. Overload current limitation).
Fig.9: Overload current limitationWhen switching off inductive loads, high induction voltages result from interrupting the current too quickly. These are limited by an integrated free-wheeling diode (switch-off energy [inductive] see Technical data). Since the current reduces only slowly, a delayed switch-off can occur in many control applications. For example, a valve remains open for many milliseconds. Switch-off times are realized that correspond, for instance, to the switch-on time of the coil.
![]() | Protection against high induction voltages To protect against voltage peaks such as can occur when switching inductive loads, we recommend to provide suitable protective circuits (e.g. with the free-wheeling diode, RC combination or varistor) directly at the actuator. |
Fig.10: Switch-off of inductive loads