Function
The solid-state relay SSR25D is an electronic power DC switch. It is designed to commutate huge electrical loads (up to 25A), driven by constant voltage of 24/36/48Vdc.
The switching element is an OMNIFET transistor 35A/70V/0.028Ω. The input and output circuit are separated by an optocoupler.
SSR25D can be used together with suitable controllers for precision control of electrical loads.
Low (safe) d.c. voltage control allows direct connection to controllers or other devices without the need of additional relays and contactors.
SSR25D has three built-in types of safety protection:
- current protection when the load current exceeds a predefined value (Ilim) the transistor goes into pulse mode, thus limiting the average load current. When the current falls below that value the normal operation of the relay is resumed.
- overvoltage protection when switching inductive loads the overvoltage peaks are limited to a certain value (Vclamp).
- thermal protection when the teperature of the case of the built-in transistor goes over a certain value, the switch is turned off till the temperature falls below that value.
Operating indicator (red LED) on the front side shows if input voltage is applied.
The solid-state relays SSR25D are filled in with epoxy rosin to protect them from athmospheric influence.