Earlier this week, we went on-site to a local hospital in Dewsbury to carry out a site acceptance test on Alpha Series AP500C Diesel generator built in our UK Factory.

These are vital tests when the generator is due to power a facility where a power cut could mean a life or death situation. The generator we tested was a 500 kVA Cummins built into a bespoke 20-foot container as per the design consultant specifications.


We arrived at the site early in the morning in the midst of classic English weather, a lot of grey skies and heavy rain. Before the testing could begin it was important that we first assessed the area we were due to run the test into, as the test would be taking place in a car park we made sure all areas were safely cordoned off.

We then laid cables between the load bank and the generator and further provisional checks from the Hospital Trust, M&E Contractors, and the Hospital Facilities Manager took place to ensure that everything was safe and ready for the test. This was quite a rigorous document (several pages) checking the control panel, alarms, warnings, and parameters on the control panel to work correctly with the main LV Switchgear as well as a final check of the premises. Once this was done the test could begin.

The first test we ran was at 0-80% load 325KW, tests which we ran for up to one hour. During running of the generator on load one of the main things we tested for was the sound levels as the set was going to be placed near hospital rooms it needed to be quiet! Our generator sound levels were 68 dba @1m and passed its test with flying colours. In fact, it was even noted by the Hospital Trust that the generator was quieter than the load bank itself.

After the 80% test, we reduced it to 25Kva to see how well the generator could cope at a low consumption – we passed this also. Testing then continued with the load increasing; 25%, 50% 75% 100% 110%.


All in all the day was a huge success and the bespoke generator passed with flying colours and will now be the backup power supply for the hospital. We love getting to build bespoke sets for our customers, especially when they are as important as the public sector!