Cummins

Back-up for Europes largest shopping complex

Issue 6 and Volume 7.

Back-up for Europe`s largest shopping complex

Cummins Power Generation have installed three gensets for department stores at Bluewater – Europe`s largest shopping complex comprising over 320 stores – situated in Kent, UK. The company has installed two type CP700-5 sets, each with a prime power rating of 580kW, 725 kVA on the roof of the House of Fraser store. The sets can meet the store`s entire power demands with the exception of the chiller load. In the event of a power failure the gensets can kick-in within 8 to 15 seconds.

The sets are located in separate acoustic enclosures, which were pre-assembled at the Cummins factory in Manston, Kent UK. The sound level rating is 65 dBA at 1m from the air intake and discharge, in free field non-reverberant conditions. An enclosure mounted exhaust silencer system helps to further minimize operating noise.

Fuel is supplied from free-standing, 1370 litre (8-hour) day tanks within the enclosures. A 3350 litre bulk storage tank at ground level within the building holds enough fuel to keep each set running for a total of 18 hours.

Cooling for the engines is by conventional radiator and fan, which also provides forced air ventilation. The sets were ordered by Haden Young of Watford, UK, and mechanical installation, including the bulk storage tank. Associated control cabling was carried out by CSL Ltd under the supervision of Cummins.

A 1000 kVA, 415/230V, 50 Hz set has been installed on the roof of the John Lewis department store providing emergency standby and peak lopping power. This set is designed to peak lop for up to two hours a day and was installed by Hills Electrical of Dartford, Kent, UK.

It is powered by a Cummins KTA38G5 engine and controlled by Cummins` Power Command Control system which handles everything from start/stop commands to monitoring, status reporting and fault diagnostics.

One of the main benefits of this system is that it allows two supplies to run in parallel when they are within specific parameters, thereby eliminating fluctuations.

The system is more precise than other methods of paralleling, particularly those that require an engineer to manually connect the genset to the mains supply.

Furthermore, the PCC system controls the fuel flow and the alternator excitation to achieve a soft ramp without excess fuel or overshoot, so there is no heavy black smoke traditionally associated with starting up large diesel engines.

The sound proofing is as with the House of Fraser sets. Air is discharged into a plenum, turned through 90 degrees and exits the roof.