FAQs - Source Transfer Switches

Source transfer switches rated below 16A are typically supplied with a mains input lead and plug and socket outlets. Some STS can used locking cable cords with the outlet sockets for added security. Larger devices above 16A are typically hardwired using input and output power terminal blocks.

Load shedding is used to turn-off loads and typically during a power outage. Load shedding is used to reduce the load on the selected primary supply (A or B) to an STS and in the case of an uninterruptible power supply will increase the amount of battery runtime available from the UPS system. Some STS incorporate load shedding as a feature which has to be set-up and accessed via the software platform supplied with the source transfer switch device.

Source transfer switches can be installed with any combination of two primary AC inputs supplies: two mains power supplies or two uninterruptible power supplies or a combination of these. Two UPS systems give added resilience to the critical loads connected.