Rectifier/ Charger

DOE-SPEC-3021-97

Rectifier/ Charger

Converts ac input power to dc output power for

charging the storage battery and provides power to

the inverter input.

Inverter

Converts the dc input power to a regulated and

filtered ac output power which is supplied to the

critical load.

Static Transfer Switch

Automatically transfers the critical loads, without

interruption, from the inverter output to the internal

bypass power source in the event of an inverter

problem. Also referred to as the internal bypass

switch.

Maintenance Bypass

Switch

Connects the maintenance bypass power source to

the critical loads while electrically isolating the static

switch and inverter for maintenance purposes. This

should be a make-before-break type switch.

Internal Maintenance

Bypass Switch

Connects the normal power source to the critical

loads through the static transfer switch while

electrically isolating the rectifier and inverter for

maintenance.

Storage Battery

The stored energy source which provides dc power

to the inverter input when the normal ac power to

the UPS module fails or in the event of

rectifier/charger failure.

Battery Safety Disconnect

Switch

Connects the storage battery to the rectifier. The

disconnect switch isolates the storage battery from

the UPS module for maintenance and personnel

safety.

Output Filter

Blocks high frequencies or steep wavefront

transients generated by the UPS or load from

feeding back into the load or UPS, respectively.

C-2