This type of UPS PANELS is generally equipped with a static bypass, sometimes referred to as a static switch.
The load can be transferred without interruption to the bypass AC input (supplied with utility or standby power, depending on the installation), in the event of the following:
- UPS failure
- Load-current transients (inrush or fault currents)
- Load peaks
However, the presence of a bypass assumes that the input and output frequencies are identical and if the voltage levels are not the same, a bypass transformer is required. For certain loads, the UPS must be synchronized with the bypass power to ensure load-supply continuity. What is more, when the UPS is in bypass mode, a disturbance on the AC input source may be transmitted directly to the load because the inverter no longer steps in. Note: Another bypass line, often called the maintenance bypass, is available for maintenance purposes. It is closed by a manual switch.
