Siemens SENTRON - Versions for 50 to 400 Hz; Versions for 500 V Operational Voltage; Residual Current Operated Circuit Breaker with N-Connection on the Left Side

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4.4.9 Versions for 50 to 400 Hz
Because of the principle according to which they function, residual current pro-
tective devices in their standard version are designed for maximum efciency in
a 50/60 Hz network. The device specications and tripping conditions also relate
to this frequency. With increasing frequency, sensitivity normally decreases. In
order to be able to implement effective residual current protection in networks up
to 400 Hz (e.g. industrial systems), suitable devices must be used. Such residual
current operated circuit breakers fulll the tripping conditions up to the specied
frequency and provide corresponding protection.
4.4.10 Versions for 500 V operational voltage
The standard versions of residual current protective devices, with their creepage
and clearances, are designed for networks up to 240/415 V alternating voltage.
Suitable residual current protective devices are available for networks up to 500 V.
4.4.11 Residual current operated circuit breaker with N-connection on the
left side
Residual current operated circuit breakers, particularly in Germany, are normally
placed at the left of the miniature circuit breakers but have the N-conductor
connection on the right. This causes problems with regard to integrated busbar
connection. Residual current operated circuit breakers in conjunction with minia-
ture circuit breakers therefore require a special busbar.
In order to make it possible use standard busbars whenever required, four-pole
residual current operated circuit breakers with the N-connection on the left are
also available. The habit of installing the residual current operated circuit breakers
at the left of the miniature circuit breakers and using standard busbar connections
can thus be maintained.