Air Circuit Breaker (ACB) Maintenance & Testing

Be safe in the knowledge you are ETCS Protected!

One of the components of an electrical installation that often get completely overlooked is the primary switch gear and means of isolation. In most installations, and particularly those serving larger facilities, the likelihood is that the main means of isolation and protection for the system is by means of an ‘Air Circuit Breaker’ which is a mechanical device of varying designs depending on brand and age.

This equipment can remain in an ‘On’ or ‘Closed’ position for months and years and without being activated and without regular maintenance; can fail to operate without warning with potential, major consequences.

The switch gear, be it ABB, Merlin Gerin, Schneider Electric, GEC, Mitsubishi or other manufacturers, is designed to act as the primary point of isolation and as a protection in the event of a fault or over current occurring on the system, thereby safeguarding the system up-line. Failure to operate can lead to serious consequences.

At E-TCS, we can provide a full maintenance service for this primary breaker unit, as well as secondary units and those further down the installation. We can design a bespoke maintenance programme to dovetail with existing routines which might include a main shutdown, withdrawing switches, cleaning, re-torqueing (not something that is done unless it is panel maintenance), lubrication (one of the most key items with ACB maintenance), greasing, functional testing, contact service and replacement of any worn or damaged components.

In addition, over current relay/ trip units can be Secondary Injection Tested using the appropriate test equipment for each brand of equipment to ensure that tripping parameters are still within manufacturer’s tolerances and that the unit will perform as designed and protect site assets/ systems.

In addition to the maintenance of ACB’s, we can carry out similar inspections and tests on Moulded Case Circuit Breakers (MCCB) to ensure correct tripping characteristics and performance.

The individual programme agreed upon, might include a full invasive inspection and physical maintenance of the whole primary and secondary panel arrangement under a controlled shutdown process. As an additional check, we can undertake a thermographic survey of the switchgear, under full load, to ensure that there is no overheating of components or connections.

E-TCS are also able to provide associated works through a network of approved partners such as High Voltage maintenance, Uninterrupted Power Supply maintenance, Generator switchover testing. For details on how we can assist with ensuring that the buildings under your responsibility are best set up for continuous and reliable service.

For more information on Air Circuit Breakers, please contact E-TCS on 01733 666657.

Air Circuit Breaker

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