connecters

[Ben Brown]

Hi All, don't know if this is the right place to post but I will.

 

Basically im building a portable layout and I'd like to know what connectors people use to separate the wires underneath. It's only for the wires going from the point motors to the switches. I'm only using (want) one control panel.

 

Any help is much appreciated,

Thanks

[Gordon H]

You really need to decide how many ways are needed, and how much current is being drawn through each pin before an appropriate connector type can be selected or suggested.

[Ben Brown]

There's 18 wires (9 points, commons from switch and points go to buses on the board) that need to be cut. I'm using gaugemaster PM 1 point motors to off-on-off switches so the current isn't going to be much.

[peter220950]

For low power applications a lot of people use 25 way D connectors from computer/printer applications. I have used them in the past for LED displays and the like, but have also seen them on a lot of layouts, though they can be a bit of a pain to wire up.

 

If you don't need a panel mounting socket, or don't want the fiddle of wiring them up, I have used male to female leads in the past and cut them in half, taking the wires to tag strips and then onto the individual boards, for example

 

http://www.ebay.co.uk/itm/3m-25-Pin-Serial-Parallel-Extension-Cable-Lead-Male-to-Female-/150462570882?hash=item230844a182:m:mwSEW1wvMWYHPmpgF3qyDZA

 

Though most people now have old ones lying around as they are used less on modern equipment.

 

With the cable threaded through a timber on the board, and with a cable tie or clamp on the cable they shouldn't pull out, and a chassis mount unwired socket or plug on the board gives you something to plug the loose wire into to keep it tidy during transit, and preventing anything getting ripped off by accident.

 

The only thing to watch is that I seem to remember that the wires don't always connect as you would expect from plug to socket, so you will need a test lamp or meter to verify the cut cable colours with the pins and cable colour on the other half when you come to put them onto the tag strip.

 

You could do the same with a pair of 9 pin computer connectors, but you're sure to find you need another wire a week later.

 

With beefier wire jumpers on 25D panel mount sockets we have used them on one part of our Club Layout, (between the 4 boards of the engine shed),

 

 

which is O gauge DCC and running Tortoise Point motors, although the point motors don't take much current the track power is 16VAC and some of the loco's can be pulling 2amps, it's not something I would recommend but there's not been a problem in over 10 years!

 

Peter

[DCB]

It is not the current drawn which matters but the peak current when you have a short as will inevitably happen.   Actually soldering these computer leads can be challenging.  

My suggestion would be to use car wiring as most ten to twenty year old cars and vans have a lot of quick release Multi pin wiring connectors with 5 to 15 amp wires eminently suitable for connecting up layout wiring and good lengths of wire, up to 10 feet or more.  Normally you can get them very cheaply from your friendly local scrap yard/ vehicle breaker.  They are not weather proof or damp proof but why would you need them to be?.

[Dagworth]

I'd seriously advise against using computer cables for solenoid point motors, the conductors are simply too thin to carry the current required, PM1s do have a hefty current requirement if you want them to throw reliably.

Are you using a Capacitor Discharge Unit (CDU) with your point motors? You will get much better operation with one.

 

Personally I would use 25way D series connectors from Maplins or similar and at a MINIMUM I would be using 16/0.2 wire from the switches to the motors.

 

Andi

[Ben Brown]

Thanks for the replies gents.

 

 

I'd seriously advise against using computer cables for solenoid point motors, the conductors are simply too thin to carry the current required, PM1s do have a hefty current requirement if you want them to throw reliably.Are you using a Capacitor Discharge Unit (CDU) with your point motors? You will get much better operation with one.Personally I would use 25way D series connectors from Maplins or similar and at a MINIMUM I would be using 16/0.2 wire from the switches to the motors.Andi

I am using a mains powered CDU from gaugemaster. I'm also going to use the wire they supplied when I ordered their point starter kit. I don't mind soldering in to D connectors. Perhaps a pic of the underside would help.

[Gordon H]

It is not the current drawn which matters but the peak current when you have a short as will inevitably happen. 

 

So what would the peak current be if you accidentally drive a CDU into a dead short?

It would be somewhat impractical to select connectors purely on that basis 'just in case'. Not only that, but in the brief time that such an event is likely to occur, it may not be the connector that suffers as it may not be the weakest link in the chain.

Certainly, a connector pin rating should be selected with a bit of spare capacity but reasonable compromises usually have to be made,

 

I am using a mains powered CDU from gaugemaster. I'm also going to use the wire they supplied when I ordered their point starter kit. I don't mind soldering in to D connectors. Perhaps a pic of the underside would help.

 

I assume you will be fixing the wires to the baseboard body rather more securely than is shown in the picture before taking the layout out and about?

Flapping and dangling wires are usually the first things to suffer damage during transport.

[BG John]

I've used D plugs and ribbon cable in the past. This was the cable to a complete hand-held control panel for a 4mm layout with points operated by a CDU. My eyesight was better in those days, and soldering all those wires at both ends wasn't too bad!

 

 

This is where it plugged into the layout:

 

This doesn't show it very clearly, but I used D plugs for the baseboard connectors too:

 

On my current layout, I'm using a 9 pin D plug to connect the hand-held controller. I only need four wires across the baseboard joint, so I'll be using a 5 pin DIN plug for that.

[Ben Brown]

I assume you will be fixing the wires to the baseboard body rather more securely than is shown in the picture before taking the layout out and about?

Flapping and dangling wires are usually the first things to suffer damage during transport.

 

Your quite right, it will all be tided up once I'm happy everything is working correctly.

 

I decided to go with these in the end. Thanks for all the replies.

[Suzie]

You can get 16/02 wires in to the solder buckets on those connectors for the point wires.

[Crosland]

If you are really concerned, use two connector poles for each circuit, even doubling up the cables. Remember thewiring of the "ground" return is just as critical as the supply side.

 

Another consideration when deciding on conductor size is the round trip length from the CDU to each motor. The longer the thicker in simple terms, to minimise resistance and thus voltage drop.

 

Andrew

[Brian]

16/0.2 wires can be soldered into the buckets of D connectors (just), you just have to ensure the strands in the wire are not over twisted of bunched up. I have found pre tinning of the bucket really helps. The hardest thing is getting the shell (case) securely on! Not a problem of course here where the D connectors are fixed. Where two D connectors are adjacent I reverse one do as it has opposite pin/socket to the other then there is no chance of reversed connection via an incorrectly plugging in lead.

I make most of my 25 way D connectors using 16/0.2mm wire. Doubling or even trebling up the wires and pins if necessary where higher current are anticipated - solenoid motors common return are one such where I always at least double up.

 

Edit to add.... All the point motor wiring in this panel (mainly the red wires) uses 16/0.2mm equipment wire, while the LED indications are 7/0.2mm to 25 way D connectors male and female alternating (4 in all) [/url]">http://

[Ben Brown]

Layout is only 8ft by 2ft. This is basically what I want to do. ( locos are dcc). The points I have already wired up on board 1 works as it should. Thanks again to the replies.

[DCB]

My experience is that the connector is usually the weak point in any electrical installation, Multipins are especially susceptible to damage and the pins are sods to clean if they do burn.  One suggestion is to connect 11 amp 16/020 cable to 5 amp connectors.  Mine is to connect 11 amp cable to far more robust 10 amp connectors, they can be crimped or soldered to taste. I solder them.

 

For a new example see    http://www.autoelectricsupplies.co.uk/product/39/category/7.  

 

 I have used DIN plugs 9 way and 5 way.  My experience is that DIN plugs fall apart if repeatedly taken apart and the pins are sods to solder 16/020 cable to and you can melt the insulation and loosen the pins doing it.   I have them on OnTrack remote controls and they are getting binned in favour of 3.5mm stereo Jack plugs,

DIN plugs are useful as the sockets are very short and I used them for my lift out section 25 years ago.  See pic 

I also use domestic wiring plastic trunking to keep my wiring neat, see pic  It makes it very easy to add new wires or fault find and supports the wires.  As an alternative I have boxed in the underside of parts of layouts with hardboard to hide and support the wires, I have a quick release either two screws or a toggle or bolt but it does stop the wiring on the upper level being snagged by fiddling on the lower level.

 

 

[Brian]

I have used latching multi pole connectors too.  I had about ten sets on my first exhibition layout - never again!  Their draw back IMO are -

a) They are not designed for continual parting and re connecting - In a car they remain connected together virtually for the life of the car or for the life of the component they are connecting to.

b ) They have no wire strain relief so tension can be applied to the wires/connector when separating the two.

c) Where continual parting and re connecting occurs a pin occasionally pushed out. 

 

My 16/0.2mm equipment wire is not rated at 11 Amp (though possibly some may be?) Its rated at 3.0Amp  http://uk.rs-online.com/web/p/hookup-equipment-wire/7482112/   and  http://www.maplin.co.uk/p/maplin-equipment-wire-16-02mm-black-10m-fa26d

 

I agree D connectors can have issues, especially if they are not plugged together correctly.  But for the modeller they offer a cheap multi pin connector which can have a cover and strain relief.  

 

A robust Multi-pin plug and socket are the Jones or Cinch style plug and sockets. But only 5Amp rated!  ebay has some mainly from the US.  RS sell them but the shells (Covers) are ridiculously priced at around £46 for the 12 way  http://uk.rs-online.com/web/p/automotive-connectors/0466034/  

 

I have spent far to many hours searching for the best multi pin plug >8 pins and matching socket at an affordable price which will suit the modeller. But so far haven't really found one. We just 'make do' by using or converting something not designed for what we need! 

[DCB]

I found my wire specs for 16/0.20 wire from the AES website, it is thin wall insulation low voltage 11 amp wire not 1000 volt 3 amp .as per Maplin, comes in 11 colours and costs 25p per metre or around £11 for a 100 metre reel  (plus postage) http://www.autoelectricsupplies.co.uk/product/70/category/114

 I don't really understand why the discrepancy in rating, I'm guessing its insulation and inductive currents on high voltage AC but the second hand 15 year LGV van wiring I have been using for point motors looks very much like 16/0.20   (it cost £2  for 10 X 3 metres lengths from Harry Buckland vehicle dismantling!)

 I agree pins can pop out of automotive connectors but they are much more repairable than computer components, you can see which pin has popped, you can get the test probe onto one pin easily without touching another and if a pin fails you can change one pin not the whole connector. They don't have strain relief sleeves but they are designed for wiring looms where many cables are taped together, 

[Crosland]

I found my wire specs for 16/0.20 wire from the AES website, it is thin wall insulation low voltage 11 amp wire not 1000 volt 3 amp .as per Maplin, comes in 11 colours and costs 25p per metre or around £11 for a 100 metre reel  (plus postage) http://www.autoelectricsupplies.co.uk/product/70/category/114

 I don't really understand why the discrepancy in rating,

 

It's called specmanship. Without the full specs it's simply not possible to make any meaningful comparison.

 

A current rating on its own tells you nothing and is worse than useless without knowing the application. What is required is the resistance per unit length. Knowing this and the current that will be flowing you can calculate the voltage drop and the power dissipation.

 

Consider the same hypothetical cable used in both a 240 V application and in a 12 V application. The resistance is .037 ohms/m (a typical figure for 16/0.2). A current of 5 Amps is flowing through 10m of cable.

 

In both cases the voltage drop will be V = I x R = 5 x .037 x 10 = 1.85 V. In the 240V circuit that's nothing. In the 12V circuit 15% which will cause problems in any circuit that is relying on 12V.

 

So, for high voltage applications a much higher current rating can be quoted for exactly the same cable. The voltage rating of a cable is the breakdown voltage of the inuslation.