Translator cars

[emoaconr]

I've seen a few of these "translator vehicles" top and tailing EMUs during Merseyrail stock movements through the Wrexham-Bidston line.

e.g. http://www.youtube.com/watch?v=nqt0604mbc8

How do these things work? I assume they "translate" diesel traction into electrical power, but during stock movements, are these really required? A 57 can drag a Pendolino without such thing (though I assume they have a form of battery?).

 

[Peter Mugridge]

They're more to ensure couplings etc. You'll find they have different couplings fitted so that locomotives can drag things they can't couple to directly. Similarly they'll have the relevant connections for the brakes etc.

the 57s can dray a 390 without one because the couplings and connections are designed to match.

 

[MggW]

A barrier vehicle has conventional couplings at one end and auto-couplings at the other. They allow MUs to be hauled by locos, but there is no electrical supply to the unit and the brakes aren't connected. So additional vehicles are required for brake force.

Translators have an electrical supply so and will connect the air so that the unit's brakes and suspension will operate. However, you then need go have an ETS fitted loco, the translators are a lot more complicated meaning more cost and maintenance, and the staff working the translators have to be trained and assessed as competent to do so.

Traction always comes from the loco.