Which hm7000?

[Alan-380265]

I am hoping to fit an HM7000 into an old loco. I see that there are a number of different pin numbers available. I was just wondering if these controllers are functionally the same and that the difference is just the type of connector used. If that is the case am I right in assuming that any pin configuration will be suitable as I will be hard wiring.

[96RAF]

The pin number determines the number of functions available. Basically the more wires the more functions.

4 pin is motor control only (not available as HM7K).

6 pin is 2 function (directional lights only - only available in HM7K as non sound).

8 pin is 4 function (directional lights plus green plus flying lead purple).

Next 18 and 21 pin are 6 function but of these 4 are full voltage and 2 are logic level. These can be hard wiring but they need a suitable adapter socket for you to solder your loco wires to.

The answer to your question is what do you need to make work in your hard wired loco as that will determine the number of pins. Motor control plus ???

[P-Henny]

Hard wiring (includes optionally fitting your own socket) will be a lot easier using the 8 pin decoder version**. But do note that the 18 and 21 pin variants do actually have additional functions that the 8 pin version does not. The differences are documented in the full HM7000 Decoder manual. An old loco, particularly if a model of a steam loco, is unlikely to need to use any of the additional functions.

Note** Wired 8 pin sockets for DIY conversion are readily available from online model shops & ebay.

EDIT: Once again 96RAF has been typing faster than me.

[ColinB]

When I convert an old loco to DCC I always use a socket, that way you can change decoders and revert back to DC if there is an issue. Hornby do 6 pin and 8 pin sockets and they are superior quality to those you get on the web, especially the latest versions. I seem to be always saying this, but by the amount of locos I have bought second hand where they have been hard wired, not many people share my view.