Can a keep alive be used on a DC only locomotive?
No. A DC locomotive’s speed is controlled by varying the voltage to the motor. A keep-alive’s purpose is to maintain constant voltage to the motor. If you installed one, you wouldn’t be able to control the locomotive’s speed, as the keep-alive doesn’t know the difference between a section of dead track and the operator’s intent to stop the locomotive.
you could use a large non-polarized capacitor if you could find one.
many keep alives use smaller super-caps that are polarized and have capacitor ratings > 1F.
just to be clear, a keep alive provide power until it is drained and if it is draining because of dirty track, no DCC commands are being received and the operator has no control of the loco
I wonder if an inductive pickup could be arranged to receive DCC commands without depending on conductivity through the wheels.
Hello All,
The OP is asking about DC, not DCC.
Hope this helps.
On DC, only mechanical solutions exist for that: flywheels, double-heading and clean track [:)].
Simon
well, in a way, yes …
but … the keep alive [depending on the capacity / size] would function more as a ‘momentum’ controll …
it’s a lot easier to use flywheels or other mechanical means …
and yes, i tried it, and it didn’t work very well … plus the keep alive [for a DC loco] would be constructed differently than one for a DCC loco, as far as i know, all the commercial offerings are for DCC not DC