Nine cars provided the power for the air-conditioning, lighting and kitchen equipment. They were numbered 2290 to 2298 and coded PHS. They were fitted with an engine compartment that was originally fitted with two GM 6.71 75 kW (101 hp) diesel alternator units. A guard's compartment was fitted centrally with the other end was a luggage compartment for 5 tonnes (4.9 long tons; 5.5 short tons) of passengers' booked luggage.
During the 1960s the GM diesels were replaced with higher powered Caterpillar D343 generator sets on cars 2293 to 2298. These new engines required the extension of the engine compartment, which then required the moving of the guard's compartment. This reduced the size of the luggage compartment, which was reduced to 3 tonnes capacity.
In 1982 PHS 2294 and 2296 were rebuilt with a toilet fitted in the luggage compartment area, the guard's compartment was fitted with air conditioning at the same time. The exterior sliding doors to the luggage compartment were relocated as well. These two cars were latter further rebuilt with a shower and new toilet facilities in the luggage area.
In 1986 PHS 2296 was repowered with Cummins NT855 engines.