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ellison pictures

This picture shows a typical Oil Circuit Breaker Replacement scheme for one
of our clients. In this particular case the replacement switchboard
(incorporating  Air Circuit Breakers and Fuse Switches) can be seen in
situ with the existing Oil Circuit Breaker equipment.

Although state of the art for their time, the Health and Safety Executive has become increasingly concerned by the continued use of Direct Manually Operated Switchgear (DMOS) such as Oil Circuit Breaker equipment. Recognising that this was potentially a very serious problem affecting a wide cross section of end users, Ellison developed a neat, cost effective replacement solution, allowing fully tested, modern equipment to be substituted for the older system.

What were the potential problems with Oil Circuit Breaker equipment?

• Direct Manual Operation - The speed of operation is determined by the operator. Closing the system too slowly can inhibit the fault making capability of the circuit breaker, with potentially catastrophic results.

• Overstressed Switchgear - Most 'OCB' equipment was installed over 20 years ago. Often, electrical systems have been upgraded with little or no concern for the fault capability of the switchgear, leaving a system which could not cope with a major short circuit.

• Insufficient Maintenance - Components become worn, oil in the breaker can thicken with obvious implications.

• Lack of Knowledge - exists in the operation of this equipment, particularly in the case of companies who have down-sized their electrical maintenance resource.

The Ellison solution involves replacement of the oil gear, with fully tested Circuit Breaker or Fuse Switch replacement units. These have been specifically designed to facilitate replacement.

A comprehensive information pack is available - detailing the reasons for concern and the possible solutions to companies considering replacement. 

Simply click on the 'Request Information' link and select Oil Circuit Breaker Replacement Pack from the drop down list on the request form.