+44 7881 300 962

SVE40 Telecomms UPS

08/90 to 08/91

SVE40 Uninterruptible Power Supply for Telecommunications Systems is a modular power supply system providing reliable DC power for telephone exchanges.

Total output is 48V at 72A (or 60V @ 60A). This output simultaneously drives the electronics in the telephone exchange and charges a lead-acid battery which continues to power the exchange in the event of a power failure.

The UPS features a sine wave input current (unity power factor).

The SVE40 consists of a rack, housing one "A40" control PCB and between one and six GR40 10/12A switched mode power supply and battery charger units. The GR40 units work in parallel, sharing the load equally and offering a measure of system redundancy.

Meets CCITT, International EMC requirements and has Deutsche Bundespost (TFTZ) approval.

I was responsible for the design of the A40 control circuit and a series IGBT trip circuit to protect the GR40 unit from high voltage transients described by VDE0160. The A40 PCB consists of five programmable timer circuits, battery current and voltage monitor, battery temperature compensation circuit, ten voltage-free user connections, alarm circuits and appropriate power supplies.

The control circuit was required to work on both positive and negative earth systems.

I also undertook a complete Type Test programme.