'Normal' Decoders as 'Function Only Decoders (Settings)

[Luke Piewalker]

I have now installed decoders in the trailing vehicles if my n gauge DMUs. For reasons of price and availability these are 'normal' decoders with motor control.

I have got them all addressed and working as desired but I was wondering if there was a consensus on if it is desirable to change/disable the motor control settings in these decoders or if it is ok just to leave them?

[cravensdmufan]

Can't answer the question but will be following with interest as I have built up a number of basic "normal" decoders having subsequently fitted sound ones.  I was thinking of using them for coach lighting.

[WIMorrison]

Most will work without a motor attached as function only but pretty well all will need a motor attached to be able to program the decoder. 

[meil]

2 hours ago, WIMorrison said:

Most will work without a motor attached as function only but pretty well all will need a motor attached to be able to program the decoder. 

Or a simple resistor across the motor terminals.

[Luke Piewalker]

I've managed to program all of mine 'on the main' without a resistor/motor. But indeed, on program track it can't read the CVs and gets very confused. All I've needed to do so far is set the address to match the motor car, and make sure the lights are mapped to the preferred function key. Just wanted to make sure that there was no chance of the decoder throwing a wobbly as it tries to control a motor that isn't there.

[JohnR]

Are there any decent function only decoders? I seem to recall in the early days of DCC there were plenty, but you dont hear about them now. 

[Ron Ron Ron]

1 hour ago, JohnR said:

Are there any decent function only decoders? I seem to recall in the early days of DCC there were plenty, but you dont hear about them now. 

 

There are a few available, from ESU, TCS, Digitrax, Uhlenbrock and Zimo.

Zimo have 8 different function only decoders listed, 4 of which are listed as “ in development”.

 

The downside is that function only decoders have traditionally been rather expensive, compared to decoders fitted with motor control.

That might be part of the reason why they’re not so common, when re-using or re-purposing normal decoders generally works out cheaper.

 

 

Ron

[melmerby]

Some decoders (e.g. Lenz) have a setting where the loco output can also be used as a function instead of motor control.

So a relatively cheap Lenz Standard + V2 can have 5 function outputs.

 

[34theletterbetweenB&D]

12 hours ago, cravensdmufan said:

Can't answer the question but will be following with interest as I have built up a number of basic "normal" decoders having subsequently fitted sound ones.  I was thinking of using them for coach lighting.

I use decoders found to have inadequate motor control to operate lighting, as they are good enough to be light switches. If you  are prepared to through wire, one motor output can operate an entire Pullman train worth of lights. Obviously slightly different to using a function for lighting, but it works perfectly well.

[newbryford]

A recent project was to retrofit a trailer vehicle at the end of a fixed rake with powered unit at the other end, with a decoder.

The fitted lights were simply a pair of LEDs wired in inverse parallel (with suitable resistor), so that either head or tail light took the track voltage and operated on DC.

It wasn't a simple task to hardwire the LEDS separately with two functions.

 

The simple solution was to fit a motor decoder that had "button control" of the motor and given the same address as the powered vehicle at the other end, so that when it was reversed, the motor output of the decoder reversed and fed directly to the LEDs. The relevant LEDs then illuminated.

Set the decoder to button control (see decoder CVs to do this)  to whatever function key controls the lights on the powered unit decoder (usually F0). Set the speed control under button to 50-75% maximum and all is well.

 

As mentioned above, I once bought a few loco decoders that didn't have the best motor control and used them to power LEDs in the likes of driving trailers and other vehicles that need controlled lighting.

Rather than fitting a resistor as a load, I connect my decoder tester with another decoder already plugged in to the same program track as the "function only" decoder I want to program. Program the CVs as normal for my function only decoder, using the decoder/tester as the dummy load.

Once done and tested, carry out a reset on the decoder in the tester.

 

 

 

 

 

 

 

Edited August 1, 2019 by newbryford

[RAF96]

On 31/07/2019 at 08:07, meil said:

Or a simple resistor across the motor terminals.

 

Or a DCC controller that can program decoders with a motor attached or not.

[Crosland]

3 hours ago, RAF96 said:

 

Or a DCC controller that can program decoders with a motor attached or not.

 

Problem is, you don't know if it's successful and you can't read anything back (unless it's a Railcom decoder programming on the main).

[Pete the Elaner]

While reading the instructions for DCC Concepts' DML-EOTS3 flashing tail lamp unit, it claimed that "This is the ONLY 4 fn, function only decoder that can be read on the program track without a dummy load".

I can't find this decoder anywhere though. Maybe it is something they plan to release in the future?

[newbryford]

3 hours ago, Pete the Elaner said:

While reading the instructions for DCC Concepts' DML-EOTS3 flashing tail lamp unit, it claimed that "This is the ONLY 4 fn, function only decoder that can be read on the program track without a dummy load".

I can't find this decoder anywhere though. Maybe it is something they plan to release in the future?

 

It lists a CL type decoder - no longer manufactured. 

 

Cheers,

Mick