Know your gear
The Powerware UPS input power may be hardwired through conduit to either a main power source circuit breaker or to an optional external bypass switch. For hardwired installations, it is recommended that you install a Powerware bypass switch to enable power transfer during maintenance or UPS downtime.
A Make-Before-Break (MBB) switch makes a new connection before it breaks the original connection. For example, if you turn an MBB switch from UPS to LINE, the bypass switch connects the load to AC input power before disconnecting the load from UPS output power.
A Make-Before-Break (MBB) switch makes a new connection before it breaks the original connection. For example, if you turn an MBB switch from UPS to LINE, the bypass switch connects the load to AC input power before disconnecting the load from UPS output power.