Automatic transfer switch panels, or ATS panels, are a development of the traditional manual changeover switches. All units comply with BSEN 60947-6-1 and are designed to fulfil certain requirements for fire safety as laid down in BS9999. All changeover solutions should be chosen to suit the load of the facility; the KVA rating of a generator is not a reliable indicator for rating an ATS panel, the primary mains supply and the power requirements of the installation should always be considered when selecting an ATS panel.
M2M – Mains to Mains
These ATS units are used where the backup supply is always assumed to be available. Usually this is because the secondary supply is coming from a separate transformer to the primary supply; or, for fire safety purposes, from two breakers from the same supply with alternative cable routing. They can however also be used when the secondary supply is coming from a generator where the GenSet is handling all of the supply monitoring, the start up of the generator and is able to isolate it from the ATS panel until the supply is stable.
M2B – Mains to Backup
These ATS units are a budget mains to generator model and include a warm up and cool down timer as well as a volt free start contact on mains failure to signal the GenSet to start the generator. They do not rely on a DC power supply to operate so will function equally well as a mains to mains system. This versatility also makes it ideal for integrating into systems with existing ATS panels which are already starting the generator, as the warm up timer prevents it from closing to load until the generator is fully up and running.
M2G – Mains to Generator
These ATS panels are designed specifically for advanced mains to generator applications where much more functionality is required than that which the M2B system offers. Fitted with a Deep Sea Electronics digital controller they are highly functional and adjustable; they are designed specifically for use with mains to generator systems and require a small but constant DC supply, normally taken from the battery on the GenSet.