Wishful thinking on ‘707s’

RAIL 828’s Open Access included several comments regarding the likely withdrawal of new Class 707 EMUs, which seems a totally stupid thing to do.

Paul Mellon suggests fitting all with a pantograph. While obviously possible, as two units are so fitted, this does not come cheap! It is very unlikely that the third rail-only trains will have a transformer fitted, as it would be totally redundant.

Three major items would need to be fitted to allow dual-voltage operation: a pantograph (expensive); a circuit breaker rated for 25kV and a fault current of perhaps 15kA (expensive); and a large heavy transformer rated at probably more than 1MW (very expensive).

Various other items would be required, such as a rectifier to convert the output of the transformer to DC, and control gear to open the circuit breaker on the approach to a neutral section and close it afterwards.

I suspect Angel Trains would be willing to do this rather than scrapping the trains, but would probably rather avoid doing so due to the cost.

Also, Robert Black suggests using Class 455s on the Isle of Wight. Nice idea, but they won’t fit without major infrastructure work! He should look at the present trains, ancient ex-London Transport Tube stock, whose height is much less than that of a ‘455’. Michelle Meadows, Bishop’s Stortford