What is the "DUMMY" m.u. connection for?

Question

On locomotives, there is a m.u. receptacle labeled "Dummy" that is place along with the normal red receptacle, what is the "Dummy" cap for?

Answer 1

I agree with Prof Who!

Answer 2

The dummy port is there so that the jumper cable can be left on the unit when not in use. Instead of leaving the live end hanging (very dangerous!), you plug it into the dummy port to stow it.

Answer 3

Highball is correct.

Locomotives not equipped with the dummy receptacle should have the MU cable removed and stored on the locomotive, usually toward the rear, inside the cowling.

The reason is simple.  With an end exposed, though 'female' on both ends, the pins can be shorted out by moisture, creating some very undesirable anomalies.

So, contrary to popular belief, the "dummy" does not refer to the conductor...

Answer 4

As said by hoghead it is for storing the MU cable. But as for it not refering to the conductor, knowing some of the engineers I work with, it does refer to them!

MU stands for Multiple Unit. which connects all the locomotives in a consist together (basically electrically), so the engineer on the lead locomotive has an idea of what the other locomotives are doing!!!!!(or not doing).

Answer 5

As said by Petero, Hoghead is correct in stating Highball got it right!