KRES VT 135 lighting

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dileTTante
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Location: Vancouver British Columbia

KRES VT 135 lighting

Post by dileTTante »

When the KRES VT 135 first appeared a few years ago I bought the DC version right away instead of waiting for the DCC version. I put in a decoder and it worked but the lights for reverse direction never functioned properly. I thought this was because I should have bought the DCC version.

Information from KRES shows how to get extra functions for interior lights. For a long time I didn't understand that a 6 pin decoder needed extra wires to do the extra functions. Most of the decoders I've seen for sale which have extra wires are for seven or eight pins.

The illustration in the instructions from KRES show connections that don't correspond to the circuit board in my model. Mine doesn't have the 'bridges' which KRES says must be removed. Attached here are a photo of the model's circuit board and an image from the KRES instructions.

English translation =
"If additional function outputs of the decoder are to be used, then the corresponding pads can be assigned
Interior lights and the side taillights / headlights are switched separately. To do this, the respective bridges BR1 and BR 2 are removed."

I assume BR1 and BR2 are rectifiers and I don't see any there on the model.

Recently I changed the VT 135 back to DC and discovered that the lights in the rear direction don't work at all.

I would like to get this sorted out, to have the basic lighting work under DC and DCC and to understand what exactly must be done to have all the lighting functions.

Any information and help about this would be appreciated.

- Terry C
Attachments
P1010768R.JPG
Dachplatine VT 135.png

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Rich1853
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Location: Melbourne, Florida USA.

Re: KRES VT 135 lighting

Post by Rich1853 »

Is the board loaded on both sides.
BR smt components are soldered to four pads, unless KRES misidentified the components as bridge rectifier.
There are different article numbers in support
Scroll down to the correct scale and railcar number to
VT 135 / VB 140 1:120
I didn't see any English translation
http://www.kres.de/support.html
Rich1853
Greetings from Melbourne, Florida USA
On the Space Coast of Florida

dileTTante
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Joined: Wed Jan 06, 2010 12:37 am
Location: Vancouver British Columbia

Re: KRES VT 135 lighting

Post by dileTTante »

Thanks, Richard. I have all the PDFs from KRES. The circuit board is double sided. The instruction sheet shows the body as separate item but doesn't show how it is fastened to the model. I haven't been able to detach it to look at the under side of the board. Holding it to the light I can see the traces, and have located the LEDs for interior lights. If no one has specific information then I'll use the photo and try to map the circuitry, then explore with a low voltage DC.

KRES images for their current FlexDec decoders show one with 8 wires and one with 4 wires + 4 pins, neither suitable for a 6 pin socket. Perhaps their earlier FlexDecs contemporary with the release of the VT 135 were different.

I used Google to translate the text in the PDF.

- Terry C

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MacG
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Re: KRES VT 135 lighting

Post by MacG »

The BR1 and BR2 were bridges (0Ω-resistors). They are already removed on your PCB. The solder pads (approx. 1x2mm) are on the right side of the "bridges". Below for the interior lighting (BR1) and above for the taillights/headlights (BR2).

A 6-pin decoder is a NEM 651 decoder with two additional function outputs (with cable, or solder pads). Like the Digitrax DZ146IN.
Lok-n-Roll.de - we send worldwide :wink:

dileTTante
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Location: Vancouver British Columbia

Re: KRES VT 135 lighting

Post by dileTTante »

Excellent! It's exactly what I needed to know. Thank you.
- Terry C

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Rich1853
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Re: KRES VT 135 lighting

Post by Rich1853 »

Rich1853 wrote:...unless KRES misidentified the components as bridge rectifier.
...
I had a gut feeling that this was the case. The correct reference designator for passive components per IEEE-315 ,
resistor is R followed by a number but since this PCB is unmarked (I would love to see how components are identified on their bill of material / part list or schematic)
jumper is JP followed by a number etc. Zero ohm resistor is also considered a permanent jumper.
Last edited by Rich1853 on Thu Apr 02, 2020 10:15 pm, edited 3 times in total.
Rich1853
Greetings from Melbourne, Florida USA
On the Space Coast of Florida

dileTTante
Posts: 843
Joined: Wed Jan 06, 2010 12:37 am
Location: Vancouver British Columbia

Re: KRES VT 135 lighting

Post by dileTTante »

Rich1853 wrote:
Rich1853 wrote:Zero ohm resistor is also considered a permanent jumper.
My guess is that the 0 ohm resistors look like the components on the DC plug in the socket which are marked 000. They measure zero resistance.

I added jumper wires as shown and the model runs with all the lights on, which is fine.

I hope to get the proper decoder soon, but for a while I'll run the VT 135 on DC. The reason is that I'm borrowing a reversing unit from Voytek which operates on DC. I want to make a straight track about 2 meters long, or long enough for two tables, and run the VT 135 or an old BTTB VT 171 back and forth at train shows.

- Terry C
Attachments
P1010790R.JPG

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