The Booyco air conditioning system being supplied for the BAE Systems RG31 Mk5 armoured personnel carrier has been successfully upgraded to significantly increase the vehicles EMI/EMC compliance.

Designed by Johannesburg-based custom climate control and air-handling systems specialist Booyco Engineering, the Mk5 air conditioning system comprises a dual cooling system with one evaporator module located in the left side of the vehicle and the other on the right.

Each cooling system has an evaporator module, condenser module and belt-driven compressor. The system is rated for operation in 55°C ambient temperatures and has a combined 15kW cooling capacity.

Grant Miller, engineering manager at Booyco Engineering, says that the upgrade of the air conditioning system involved the replacement of both the evaporator and condenser brushed fans with brushless fans in order to reduce the electro magnetic interference on the radio signals.

“The problem with brushed fans, as originally installed in the vehicle, was that every time the brush passes from one commutator to the next, a spark was created. This spark sent out a spike, creating electromagnetic interference with the radios,” Miller elaborates.

“The installation of brushless fans alters it to an electronically commutated type fan so it does not generate as much interference.”

Miller adds that the upgraded RG31 Mk5 air conditioning system has exactly the same cooling capacity and air flow as the original air-handling system.

Miller elaborates that, due to the significant level of EMI reduction, the upgraded system substantially increases the range of the vehicle radios. “Because of the reduced EMI, the radios have a longer range so they have further communication range capabilities.”