Advice on LGB MTS Switch Decoders for Points

[Walts-Playmobil]

Advice on LGB MTS switch decoder.
I have seen locos with MTS decoders in run on D.C. But if the switch decoder is connected to the track and D.C. applied what will happen to the switch decoder?
Any advice would be appreciated

 

[HBBahn]

I don't think the point decoders work the same way.

From what I can recall, the MTS point decoders need a digital supply, and if DC is applied, it destroys the decoder.

 

[whatlep]

Advice on LGB MTS switch decoder.
I have seen locos with MTS decoders in run on D.C. But if the switch decoder is connected to the track and D.C. applied what will happen to the switch decoder?
Any advice would be appreciated

Can I ask why you would even consider having a switch decoder coupled to a DC-fed layout? As has already been answered, the switch decoders only work with DCC AC.

DC shouldn't damage a decoder (at least up to 27 volts as per NMRA specifications). It's perfectly acceptable to use a DC voltage source to program the switch module via the 55015. On the other hand, why tempt fate....

 

[ntpntpntp]

Can't say I've played with an LGB point decoder, but with my NCE point decoders there's no real problem feeding them with DC rather than DCC - they just won't see any valid DCC instructions and so don't react.

In order to allow me to continue to operate my points on DCC while the track itself is DC powered (eg. for visiting locos), I ran a separate pair of wires as a DCC bus for the point decoders rather than connecting them directly to the track.

 

[Philbahn]

Advice on LGB MTS switch decoder.
I have seen locos with MTS decoders in run on D.C. But if the switch decoder is connected to the track and D.C. applied what will happen to the switch decoder?
Any advice would be appreciated

Walter not too certain what your planning. Can you expand why

 

[stevelewis]

Hi Walt

The just dont work, I have tried it, ( out of idle curiosity as Graham Farish instructions used to say!!)

not a good idea though to expose them to DC for too long

 

[ntpntpntp]

not a good idea though to expose them to DC for too long

Why do you say that Steve?

As I see it there's no absolutely reason to assume they'll be harmed at all, given that they're designed to handle the equivalent DCC alternating voltage. They'll draw a little power when the microcontroller chip wakes up (just like with a loco decoder), but without any data packets to give them instructions they'll just do nothing and won't switch on the outputs to the point motor either.

 

[stevelewis]

not a good idea though to expose them to DC for too long

Why do you say that Steve?

As I see it there's no absolutely reason to assume they'll be harmed at all, given that they're designed to handle the equivalent DCC alternating voltage. They'll draw a little power when the microcontroller chip wakes up (just like with a loco decoder), but without any data packets to give them instructions they'll just do nothing and won't switch on the outputs to the point motor either.

Cant give you a definitive answer to that just remebering what I read in the instructions of early Lenz accessory decoders which stated, that they should not be subjected to anything other than the output of a DCC central station, Mind you of course that was around 15 years ago so things may not be the same these days.

Cant see any apparent reason though for actually using DC on a point decoder, Can You!!:thinking:

 

[whatlep]

not a good idea though to expose them to DC for too long

Why do you say that Steve?

(snip)

I share Steve's wariness, based (if I'm honest) only on the fact that components (for example light bulbs) supplied with AC tend to last longer than those fed a diet of DC at the same voltage.

 

[ntpntpntp]

Cant see any apparent reason though for actually using DC on a point decoder, Can You!!:thinking:

Well I read the original question as implying that the point decoders would be wired to a track that sometimes may be powered by DC rather than DCC. That's how my line was (and I had no problems other than an inability to change the points remotely when running DC) until I rewired the point decoders onto their own DCC feed as mentioned in my earlier post.

 

[ntpntpntp]

I share Steve's wariness, based (if I'm honest) only on the fact that components (for example light bulbs) supplied with AC tend to last longer than those fed a diet of DC at the same voltage.

As I see it, the electronics in the point decoder are powered using DC rectified from the DCC input anyway, so feeding DC to the input just means the rectification stage is either redundant or simply serves to reverse the DC polarity to suit the electronics (depending on which way round you feed in the DC).

 

[stevelewis]

All this has jogged a memory,

In my early DCC days I actually did something silly to a digital controller ( Lenz) I had the digital system switched on, and for some reason I connected an analogue controller to the track and turned it ON ( can't remeber why!!) the result was the screen on the dig. controller displayed a set of unreadable symbols, and it had to be returned to the supplier for unscambling!! Which they did at no cost and without question

I think they call it learning by experience!!

 

[Andrew WH]

Hi All

No problem!

I have 3 LGB points decoders connected directly to the track for flicking the points. I have occasionally used my starter set DC controller on my layout. Never had an issue with LGB points decoders; they just "ignore" the DC. For DCC I am fan of the Lenz 100 system.

Why was using DC when I have DCC?
[*]For [strike]playing[/strike] testing pantographs defaullt operation on some Sizzy Loco's[*]When some of my neices and nethews where younger and visiting they could operate (play with a loco on the line).
Andrew WH

 

[Walts-Playmobil]

Many thanks for all the advice. The reason I needed it is a friend of mine has the LGB MTS system, and is due to have an open day.
It is possible that some one will come with a DC loco and went to run it.
It seems that will be O.K. but if they need to operate the points a separate Bus Maine will have to be installed.
I?ll stick to Playmobil and let the kids play with it.

 

[whatlep]

Many thanks for all the advice. The reason I needed it is a friend of mine has the LGB MTS system, and is due to have an open day.
It is possible that some one will come with a DC loco and went to run it.
It seems that will be O.K. but if they need to operate the points a separate Bus Maine will have to be installed.
I?ll stick to Playmobil and let the kids play with it.

Huh?
There's no problem running a DC loco on MTS (at least for a short while), provided you can tolerate the screeching noises emitted by the AC signal going through the motor. The setting up routine varies with what MTS central station you have. If your friend is using a version 3 central station (55006), there is no setting up to do as the 55006 recognises analog (DC) locos automatically. The DC loco is run as loco zero whichever MTS system you use.

The points will operate just fine as they'll still be receiving the DCC signal (as will the DC loco).

Of course the golden rule of not having both DC and DCC supplies connected to the track at the same time applies.