Electronic overspeed switch

Johannes Huebner has
developed the electronic
overspeed switch EGS(H) 41.

Attachable to existing
encoders, this safety solution
is suitable for applications
ranging from steelworks and
rolling mills to mining, crane
systems and nuclear power
plants. When an incident
occurs, the operator of the
system can use the switch to
transition to ‘Safety Limited
Speed’ or ‘Zero Rotation’ and
commence servicing and
repair immediately.

The EGS(H) 41 also
benefits operators of
industrial systems by
increasing occupational safety.

The overspeed switch is said
to be the only one of its kind
worldwide which is certified
to the international IEC 61508
standard for use in safetyoriented
applications up to
Safety Integrity Level (SIL) 2
and to Performance Level
(PL) d in accordance with
German industry standard
DIN EN ISO 13849.

The device comes as
standard with two separate,
galvanically isolated switches
for rotation speed monitoring,
each independently
programmable for over- and
underspeed from a value of
0.5 min-1.

The EGS(H) 41 possesses
functions for integrated
downtime and slip
monitoring and a diagnostic
switch for monitoring the
device’s safety functions. “Our
overspeed switch minimises
safety hazards such as a system
suddenly going into operation
or abrupt increases in rotation
speed during maintenance and
setting-up work,” Huebner
project engineer Bernhard
Herbst explained.