Wiring for pont motors

QUOTE (Doug @ 6 Apr 2008, 00:26) <{POST_SNAPBACK}>I have some 8-core cable that I uses to send power and commands to the points and it sends signals back to LEDs on the control panel.

See my blog here for info and a photo.

8 x 0,22 mm² AWG 24

Conrad item # 065118-62

***HI - sorry but Ribbon cable is simply not usable with High Current Solenoids.

Doug...sorry to contradict you but you can use that fine wire only as the Conrad point motor has quite low current needs....even then its marginal. However, if the questioner wants to power Peco or similar they have a momentary power peak of 4+ amps.... and 24 AWG is far too small.

If reliable results are wanted then for Peco point motors I would never recommend using anything lighter than 18AWG (1.02mm dia) as a very minumum and then only if the wire length was less than a metre, 16~15AWG (1.3~1.5mm dia) if less than 10 metres and 14~13AWG(appx 1.6mm~2mm dia) if more.

Distances are calculated as 2x distance between power supply and point motor as voltage drop happens as a result of the "round trip" that the power has to take to and from the solenoid.

In simple terms, 240 volt bedside lamp twin wire minimum, ideally 20 amp mains cable.

These recommendations are NOT to do with current carrying ability, but with voltgae drop which must always happen if wire is smaller than it should be!

Richard
DCCconcepts

QUOTE (TonyDaly @ 6 Apr 2008, 18:01) <{POST_SNAPBACK}>Hi Richard.
Is 16/0.2 suitable for Peco motors ?
Regards.
Tony Daly.

*** Hello Tony... Wire is a pain to understand as the way its labelled is confusing to most but with a little work you can easily calculate this sort of thing using this excellent calculator: http://www.csgnetwork.com/circlecalc.html and refer back to an AWG chart etc...

Short answer is to me, NO, I don't think it is adequate for anything more than 300mm or so droppers to the DCC bus.

16x.2 = appx 0.62mm total copper area.

18gauge is the lowest I'd ever use and then only for short runs and this is appx 0.82mm copper area - the equivalent of 26/0.2.

Personally I'd use something like Altronics (AU) heavy hookup wire which is 32/0.2 or for UK modellers Maplin 3202 (32/0.2) equipment wire - example part # maplin XR32K - or somewhat heavier for long runs. Its available in a variety of colours in all cases.

Richard
DCCconcepts

QUOTE (Richard Johnson @ 6 Apr 2008, 14:06) <{POST_SNAPBACK}>*** Hello Tony... Wire is a pain to understand as the way its labelled is confusing to most but with a little work you can easily calculate this sort of thing using this excellent calculator: http://www.csgnetwork.com/circlecalc.html and refer back to an AWG chart etc...

Short answer is to me, NO, I don't think it is adequate for anything more than 300mm or so droppers to the DCC bus.

16x.2 = appx 0.62mm total copper area.

18gauge is the lowest I'd ever use and then only for short runs and this is appx 0.82mm copper area - the equivalent of 26/0.2.

Personally I'd use something like Altronics (AU) heavy hookup wire which is 32/0.2 or for UK modellers Maplin 3202 (32/0.2) equipment wire - example part # maplin XR32K - or somewhat heavier for long runs. Its available in a variety of colours in all cases.

Richard
DCCconcepts

Hi Richard.
Could you double up 16/0.2,in other words use 2 wires for each run ? Would that equal 32/0.2 ?
Regards.
Tony.

QUOTE (digger1962 @ 5 Apr 2008, 16:53) <{POST_SNAPBACK}>I am trying to come up with a way of not having loads of trailling wires under the baseboards to carry the power to my point motors.....
I agree with Richard that 'Ribbon cable' is not adequate for any solenoid point motor such as Peco. As he says, the main problem is the voltage drop - the short burst of several amps from a CDU won't damage such cable but the voltage drop caused by this small cable may rob the motor of sufficient energy to properly operate.

You can use larger wires and there are several ways of confining these under a baseboard so they don't dangle about.
(1) bore holes in the bearers under the top surface and thread the cables through, bunching them together with cable ties or self-adhesive tape of some sort;
(2) use 'P' cable clips screwed to the bearers to hold the cables;
(3) use cable ties fitted through self-adhesive plastic bases stuck to the baseboard;
(4) there is a plastic spiral wrap which can be put round cable runs which allows cables to come out wherever you want them to, but which otherwise holds the cable firmly together;
(5) the most expensive way is to use the small cable ducting with slotted sides sold for industrial control panel construction.

On my own layout I've used a combination of methods (3) and (4) depending on the number of wires involved.

If you've not done much model railway construction before, I strongly recommend you carefully mark every cable in some way, and keep a list of cables, where they run from and to, any plugs and sockets they go through and how they are marked. A notebook is sufficient, although I've also used a computer spread-sheet program to draw up my lists.

Regards,
John Webb

QUOTE (Richard Johnson @ 6 Apr 2008, 13:06) <{POST_SNAPBACK}>*** Hello Tony... Wire is a pain to understand as the way its labelled is confusing to most but with a little work you can easily calculate this sort of thing using this excellent calculator: http://www.csgnetwork.com/circlecalc.html and refer back to an AWG chart etc...

Short answer is to me, NO, I don't think it is adequate for anything more than 300mm or so droppers to the DCC bus.

16x.2 = appx 0.62mm total copper area.

18gauge is the lowest I'd ever use and then only for short runs and this is appx 0.82mm copper area - the equivalent of 26/0.2.

Personally I'd use something like Altronics (AU) heavy hookup wire which is 32/0.2 or for UK modellers Maplin 3202 (32/0.2) equipment wire - example part # maplin XR32K - or somewhat heavier for long runs. Its available in a variety of colours in all cases.

Richard
DCCconcepts

Hi Richard.
Sorry to be a pain but could you double up 16/0.2,in other words use 2 wires for each run ? Would that equal 32/0.2 ?
If not would something like this be suitable.
http://www.rapidonline.com/productinfo.asp...p;uos=Reel,100m
Regards.
Tony.

QUOTE (TonyDaly @ 7 Apr 2008, 16:27) <{POST_SNAPBACK}>Hi Richard.
Sorry to be a pain but could you double up 16/0.2,in other words use 2 wires for each run ? Would that equal 32/0.2 ?
If not would something like this be suitable.
http://www.rapidonline.com/productinfo.asp...p;uos=Reel,100m
Regards.
Tony.

**It's Never a pain Tony... and:

(1) yes, doubling it would double the copper to 32/02.
(2) yes, the wire from rapid looks just fine - much better colour range and price than maplin too!

Richard

I have to say that from the hundreds of Peco or Seep motors and before that the H&M solenoid motors I have encountered and used, I have found the following to be a good rule of thumb and never had any volt drop problems when throwing one motor at a time (Multi ends thrown together are another matter).

1) Always use a CDU (preferably a heavy duty type) between the supply and the first point switch If possible use 24v ac though 16v will be ok.
2) For wire runs of up to 2.5m then 7/02mm is ok
3) For wire runs of 2.5m to around 5m then 16/02mm is ok
4) For wire runs over 5m then use 24/02mm or 32/02mm dependant on length of run.
5) Ensure the return wire is of large enough size to accommodate the return current flow and any volt drop.

The main problem with the larger sizes of wire is often getting the wire/s into the terminals!

My former exhibition layout broke the above rules and used mainly 20 core flexible cables of 7/02mm core size as that was all I could obtain at that time. Connecting the cable to the layout at both ends via 'D' connectors and one cable used a SCART plug/socket. The cables had a run of approx 15 to 18feet (approx 4.5m to 5.5m) from panel to furthest point motor/s. While I trebled up the return wires (Cores 18. 19 & 20), I never had any problems operating the furthest points via stud and probe (with a HD CDU).

QUOTE (Brian @ 8 Apr 2008, 22:58) <{POST_SNAPBACK}>I have to say that from the hundreds of Peco or Seep motors and before that the H&M solenoid motors I have encountered and used, I have found the following to be a good rule of thumb and never had any volt drop problems when throwing one motor at a time (Multi ends thrown together are another matter).

1) Always use a CDU (preferably a heavy duty type) between the supply and the first point switch If possible use 24v ac though 16v will be ok.
2) For wire runs of up to 2.5m then 7/02mm is ok
3) For wire runs of 2.5m to around 5m then 16/02mm is ok
4) For wire runs over 5m then use 24/02mm or 32/02mm dependant on length of run.
5) Ensure the return wire is of large enough size to accommodate the return current flow and any volt drop.

The main problem with the larger sizes of wire is often getting the wire/s into the terminals!

My former exhibition layout broke the above rules and used mainly 20 core flexible cables of 7/02mm core size as that was all I could obtain at that time. Connecting the cable to the layout at both ends via 'D' connectors and one cable used a SCART plug/socket. The cables had a run of approx 15 to 18feet (approx 4.5m to 5.5m) from panel to furthest point motor/s. While I trebled up the return wires (Cores 18. 19 & 20), I never had any problems operating the furthest points via stud and probe (with a HD CDU).

***Brian - I don't often disagree with you but in this case, sorry, I do.

I don't argue that you haven't used the wire sizes quoted, but you HAVE had voltage drop problems, even though you may not have seen them, as the laws of physics say you must have ...and in a way, you also acknowledge it by your recommendation for a 24 volt CDU - a 24 volt CDU would not need to exist for a solenoid rated at a much lower voltage if the power was able to get there properly!

Generally I think that the two smaller sizes you quoted are really very, very marginal, and I really don't think their use should be encouraged in any way -add imperfect soldering, temptation to use save a few pennies & smaller wire for longer lengths etc and marginal wire will continue to create the cnstant problems that novices have with peco point motors...

I just think its wrong to perpetuate the raliway modellers myth that any old wire will do, when the truth is, it simply won't.

You also have to remember that a point motor 2.5 metres away from the power supply has a 5m wire run - the rating & voltage drop risk is for there and back!

As to the smaller 7/0.2 size, No, No, No... Never: sorry! Its about the same as alarm/telecom wire in cross section and I'd have to very strongly disagree: It is totally UNsuitable for point motors.

7/0.2 is regarded as a super lighweight hookup wire which has a huge voltage drop under load - and to me, could never be considered even marginally OK for a solenoid point motor that draws a peak of several amps.

Its effectively a tad lighter than 24 gauge and its equipment rating is at best 3.5 amps and its power transmission rating - the one we are talking about using - is ONLY 1/2 AN AMP. ie, its marginal even for a very short dropper!

Kind regards

Richard

Hi Richard,

Now I'm confused !!

A short time I sent you a copy of my proposed wiring diagram for comment.

If you will recall I am intending to use a 16 x 0.2mm bus from the CDU with 7 x 0.2mm droppers from the bus to the Seep point motors. The returns to the probe on the mimic board are all 7 x 0.2mm.

It would now appear that this set-up is inadequate though, at the time, you did not comment on the wiring sizes. I have now bought about 2Km of 7 x 0.2mm wire which looks as though it might be redundant.

Regards,

Expat

QUOTE (Expat @ 8 Apr 2008, 16:49) <{POST_SNAPBACK}>Hi Richard,

Now I'm confused !!

A short time I sent you a copy of my proposed wiring diagram for comment.

If you will recall I am intending to use a 16 x 0.2mm bus from the CDU with 7 x 0.2mm droppers from the bus to the Seep point motors. The returns to the probe on the mimic board are all 7 x 0.2mm.

It would now appear that this set-up is inadequate though, at the time, you did not comment on the wiring sizes. I have now bought about 2Km of 7 x 0.2mm wire which looks as though it might be redundant.

Regards,

Expat

Hi Expat.
I was going to do the same but you can double up on the 16/0.2 which would make it 32/0.2 & then use 16/0.2 as droppers. That should make you ok.

Sorry Richard,
I have used 7/02mm for many applications including track feed wires and point motor control and indication circuits back to panels etc. I have never once experienced any failures to throw or trains caused to run slow due to volt drop (that's of course up to certain limits).

7/02mm will be ok when used on smaller layouts (about 6 x 10ft max) while 16/02mm will be fine for virtually all other layouts used in the UK home.

To prove this, take two by 2.5m (approx 8 feet) lengths of 7/02mm and connect to a Peco PL13 or Hornby point motor and then connect one wire to a 16v ac supply. Dab the other wires stripped end onto the opposite 16v ac terminal. The motor will fly over. Now add a second motor to the first's wiring, at the firsts motor end. Do the same test and again the two motors will fire without problem! This is without a CDU. While larger sizes of wire are "nice to have's" they aren't absolutely necessary on smaller N or OO layouts.

So volt drop on both 7/02 and 16/02mm is perhaps not such a big issue as you're leading people to believe! On your large layout you will most likely need a bigger size of wire to overcome VD, but in the main, the average UK home user with a 4 x 8 or 6 x 10 or there about's layout size will be ok with 7/02 and or 16/02mm, unless they are operating two ends (e.g. crossover) at some distance away from the switch, where 16/02 is then preferred for the point motor feeding.

I have wired at least five club layouts and four home layouts in the last few years and used a mixture of 7/02 and 16/02mm wire to feed tracks and points without any problems and at least five of these have used 16v ac as the CDUs supply.

I personally use 24v ac input to my CDU as that is what my Kent Panel Controls transformer provides at 100ma. This transformer (TX-5) has one 24v output specifically for CDU use (2 x 16v ac and 1 x 24 v ac outputs). I also use their CDU, a CD-2 unit.

So, use larger sizes of wire if you wish. Its never a problem to over size, but if youre using a typical sized layout the wires sizes quoted will be fine
I think we stand to differ on this one.