BS 8519

A new BS 8519, which is the code of practice for 'Selection and installation of fire-resistant power and control cable systems for life safety, fire-fighting and other critical applications.', was released in 2020.

The original BS 8519:2010 only required an ATS to have a By-pass switch. The new standard requires that Automatic Transfer Switches are Class PC with Motorised Switches and a By-pass switch.

BS 8519 : 2020 states that an ATS should meet the PC classification (not circuit breakers or contactors) conforming to BS EN 60497-6-1 and must be a single component from the manufacturer. Plus, where occupation of the building is conditional upon the availability of the life safety and fire-fighting equipment, a single or dual bypass component should be provided to enable the ATS to be maintained without loss of service from the critical plant:

To ensure conformity the Mertech PC Life Safety ATS comprises both components, the ATS and the ByPass:

  1. The Mertech ATS includes a Socomec Motorised Switch with an integrated door mounted controller.
  2. The ByPass includes two Socomec switches, a make before break ByPass switch and an ATS isolation switch.

The parts are supplied as two conjoined but isolated components to ensure safe operation during maintenance. Once the ATS is bypassed and isolated it is safe to work on, even the control terminals are disconnectable to ensure remote voltages can be isolated.

The BS 8519 : 2020 also requires that the ATS must be suitable for AC33A or B utilisation category. The Mertech PC Life Safety ATS are rated for AC31 and AC33. The two different categories are clearly identified on the units Data Sheet and inside the component.

We still manufacture the original 2010 (Class CC) specification as not all customers specify BS 8159 for Life Safety ATS.

For prices of Life Safety ATS Class PC to BS 8519:2020 or Premium ATS Class PC please call the office.