Anyone ever use a Lais decoder?

[gavino200]

I'm taking inventory of my decoders, and I found a bunch of Lais decoders that I got from Aliexpress. Threre's only one unaccounted for and I don't remember if I put it in something. I'm trying to decide whether to ditch these or use them. Ideally with automation I'd like to move to using more reliable decoders.

 

These are them:

 

Motor decoders with "stay alive" capacitors.

 

Simple function decoders

[chadbag]

I have a dozen approximately of their function decoders.  I've tried one or two in a Shinkansen to control the chad-JNS-light boards.  They work fine for that.

 

I think people were using the motor decoders as poor-mans bipolar cab car light decoders.  Never done that myself.   I wouldn't ditch them...

 

[Dani]

Hi,

 

May be LaisDCC decoders have changed, but I tried them some years ago and I had long conversations with the builder because the motor voltage output is not linear, so with the speed knob at 20% it can run faster that with the speed knob at 30%. These are some of the tests I did in 2015:

 

I connected a brand new LaisDCC decoder to my ESU tester, and measured the output voltage to the motor in each throttle position. I started from 1% of throttle until 50% of throttle. I measured also decreasing the throttle from 50% to 1% in the same points. And finally did the same with a brand new D&H DH05 decoder, more or less with the same characteristic than LaisDCC (0,5A, 2 functions...). That's the result:

 

* D&H is stable and provides exactly the same voltage at the same throttle position (doesn't matter if you are accelerating or decelerating)

* D&H acceleration curve is progressive

* LaisDCC is completely unstable, in some point having the throttle in the same position the voltage changes more that one volt continuously

* LaisDCC is not providing the same voltage at the same throttle points when you decelerate than when you accelerate

* LaisDCC acceleration curve is completely unstable

* LaisDCC provides an extremely high voltage from the beginning

 

 

Blue line is the output voltage of the D&H at each throttle position. Red line is the voltage of the LaisDCC increasing speed from 0 to 50%. Green line is LaisDCC decreasing speed from 50 to 0%.

 

I also burned some LaisDCC decoders in locomotives like the Tomix Cleanner, which drain more current than a normal locomotive. So I think 0,5Amp is too optimistic for LaisDCC decoders.

 

But I repeat, this was 7 years ago, may be they have changed. 😞

 

Anyway, I use them for cab/end car lights as they can switch polarity so you don't need to modify the light boards.

 

 

Edited April 2, 2022 by Dani

[gavino200]

Thanks Dani. I think I'll use mine as function decoders!

[Dani]

Hi,

 

To use them as function decoders, may be this guide helps: http://www.clubncaldes.com/2018/03/kato-10-286-series-885-white-sonic-dcc.html

 

To set up LaisDCC decoders to use the motor wires as a function output, with polarity depending on the direction of travel and F0, these are the CV that you have to set:
CV61=68 and write in CV133 the desired intensity (value from 0 to 255). Normally a value between 20 and 50 is enough so you don't have to change the existing resistor of the light board. 😉

 

[gavino200]

Thanks, Dani! You rock!! 🙂