Aristo (Crest) automatic reversing unit ART 11091-01 - PROBLEM

[KeithT]

I have fitted one of the above to my rack line but ran into problems from the start.
I am using LGB transformer 50110 and throttle 52120, the loco is an analogue Ballenberg tank.
At the first try the loco ran on the mid-section of track ie between the diodes but stopped at the opposite end of the section of track with a diode, it did the same at a second try. Next I placed it beyond the other diode at the top of the rack, it ran back until it straddled the diode and stopped.
Since then - nothing.
The power light is illuminated in the Crest unit (one direction only).
Could I have blown the reversing unit or possibly a diode?.
My soldering is iffy to say the least but I made all the connections at the first attempt and without my usual trauma.
I note that the Crest unit is rated 12v whereas the LGB transformer delivers up to 20V.
Stumped!

 

[Gizzy]

Do you have a multi-meter Keith?

If so are you getting any voltage on the rails, in the middle section between the diodes?

Is this changing from positive to negative in accordance with the timings set up to run your shuttle?

If the above are okay, then check the voltages for the end sections, 'protected' by the diodes....

 

[ntpntpntp]

Don't have one of thse units, but I'm wondering if it could be upset if the loco is one that's somehow wired to run the opposite way to what the unit expects? I'm trying to remember if Aristo locos run the wame way as LGB by default (I think they do, but I know some Bachmann don't!)

Looking at the instructions for the reversing unit, it says it handles 12v-22v so that should be ok. Are they definitely the correct diodes (3 amps or more recommended for G scale)?

As gizzy says, check the track voltage and polarity with a multimeter.

 

[KeithT]

Thanks guys I will check with a multimeter; the diodes are the correct ones 1N5400 3Amp (took some finding); I don't have an Aristo loco but I am sure they run 'same way round' as LGB. Bachmann locos have a polarity switch.
One other thing I will check will be to run a different loco in case the one I tried has some 'odd' circuitry - I bought it second-hand; it is def' not digital but I know it was refurbed professionally before I got it.
BTW Would I damage a digital loco if I ran it with the reversing unit? I have a digital LGB FO rack loco.

 

[Gizzy]

BTW Would I damage a digital loco if I ran it with the reversing unit? I have a digital LGB FO rack loco.

The LGB 50110/52120 should be providing linear DC to the ART 11091-01 unit, so unless the ART somehow changes the output to PWC, then you should be okay to use a digital loco on your rack line.

http://www.aristocraft.com/techinfo/manuals pdf/11091reversingunit.pdf

Looking at what details I can find out about the ART unit on the web as per the above linky, I wouldn't think it is PWC, but might be worth checking by e-mail to Mr Polk....

 

[KeithT]

Thanks guys I will check with a multimeter; the diodes are the correct ones 1N5400 3Amp (took some finding); I don't have an Aristo loco but I am sure they run 'same way round' as LGB. Bachmann locos have a polarity switch.
One other thing I will check will be to run a different loco in case the one I tried has some 'odd' circuitry - I bought it second-hand; it is def' not digital but I know it was refurbed professionally before I got it.
BTW Would I damage a digital loco if I ran it with the reversing unit? I have a digital LGB FO rack loco.

If the output is linear DC then no, but if it is PWC (Pulsed Width Control) then yes.
On the Crest Train Engineer, you can select these, but I am not aware if this is the same for your unit Keith....

Gizzy
There are no options with the reversing unit so I assume it is simply linear DC.
The unit does incorporate "soft start momentum control".

I probably won't try it though!!