Elektra S series main switches with a low voltage circuit breaker provide protection against automatic restarting when power is restored following a power cut. They fulfil the requirements of DIN EN 60204 Part 1, clause 7.5 by means of a low-voltage circuit breaker coil, which has a mechanism that after any power cut causes the switch to jump back into the 0 position. If there is no power, the switch cannot be turned on.
Additional equipment
- Power bus connection
- Extra terminal clamp for control current circuit
- Auxiliary contacts' function
ELEKTRA main switches of the S series with undervoltage release comply with this requirement owing to an undervoltage release coil which, after power failure, makes the switch jump back to the ”off“ position by means of a mechanism. If the voltage has not been applied, the switch does not click. For example, please see opposite functional diagram showing the incorporation of the emergency-off push button (NC con-tact) and PTC temperature feeler (NC contact) into the control circuit. The coil trips the main switch if the control circuit is interrupted.