Because we will be using a computerised, Raspberry Pi based, DCC control system with wireless hand controllers to control Die Keinnamebahn at exhibitions I wanted to protect the system from induced spikes or drop outs in the mains electricity supply.

Dropouts can occur if someone accidentally, or inadvertently, unplugs a mains supply lead to the layout or if something trips an RCD protection circuit at the exhibition venue. By using this 500 watt UPS we will get 5 vital minutes of protection whilst we either instigate an orderly shutdown to protect the computer systems or we can carry on controlling the layout if the electricity problem can be corrected quickly.

To this end I have bought a second-hand HP T750 GS unit from a U.K. based supplier, UPS Trader, a U.K. online retailer. The unit arrived looking brand new with new batteries fitted and new cables and a 12 month warranty. The UPS cost me £53 inclusive of delivery, a saving of £212 over a new model. I can vouch for the excellent after-sales service I have received from this company