M7 LSWR livery and which carriages

Hi Kevin,

Nothing beats a bit of experimenting. Digital multimeters are pretty much all the same. For continuity set it on resistance (omega) at 200 with the black cable in the common socket, red in the V,omega,A socket. Switch track DCC on. Touch one probe to one rail, other to the other. It will read 1, which means resistance, i.e. no continuity. if it is around 0.3 you have a short. Touch the same rail with both probes and it will read 0.3 or thereabouts, which means current between the probes (continuity). If it is 1 it means you have very dirty track. You can in fact use the multimeter to see whether you need to clean the track.

Take a locomotive, place in a cradle upside down. Touch 2 wheels with the probes on the same side, then touch one on each side. If you find resistance between wheels on one side a pickup is not working. If you find continuity between sides you have a short. Again dirty wheel treads can be easily detected.

Polarity is simply setting the dial to DC volts (20V, the symbol is a straight line above a dotted line) and seeing whether the rails are + or -.

Regular multimeters are are a compromise with DCC, as it is a cross between DC and AC (half square wave AC I believe at whatever voltage your system works at, mine reads 14.5V but it is rated at 16V). You can get multimeters designed for DCC. Not necessary for checking continuity or polarity and most of us can live with an inaccurate voltage reading.

Resistance/continuity will be the same if you swap the leads over. It doesn't care.

Put a new battery in that multimeter, and start probing. You will soon get into the habit of testing track, turnouts, locomotives, switches, polarity changers, especially DPDT ones, track feeders, soldered connections, transformer output…in fact anything electrical, whether it is DC or DCC. It saves a lot of grief down the road (or should I say rails!). Of all the tools I have this one gets used the most.

Nigel

Hi Nigel. Thank you for your reply. Now that I am on the to getting my laptop working, I will have to buy some new toner. Then I can print out the instructions for reference. In the meantime there seems to be an issue with my email address ( or email addresses? ) I went to my local Samsung help centre today to ask if they would transfer my contacts from my iPhone to my Samsung? Which they did but the phones were plugged into something? And it would seem that they took a share too? But they couldn’t do anything with my email address and said that it wasn’t working.Best wishes Kevin 

Excellent post Nigel,  Kevin you say you have the two points - one working perfectly and one shorting. . Use Nigels methods and work your way slowly over BOTH points. . First probe a section of the good one, then do the same on the faulty one see if you get a different reading which might flag up where the fault is
Cheers

Matt

Hi Matt. Thank you. That is the point? Both of them are wired exactly the same, Insulated fish plates and all.Best wishes Kevin 

Hi Nigel.  Yet another reply. Today I have been checking the wiring, and the Inglenook plank/module works fine by itself, but, as soon as it is clamped to the fiddleyard nothing runs , that obviously means that the short is on the fiddleyard. But after spending a lot of time checking the point wiring l used another plank that is wired okay, as a pattern, then the fault must be on the fiddleyard, enter multimeter “stage left”. But not tonight, I am going to rest a while.  Best wishes Kevin 

Possibly the supply wires to your Fiddle yard are wired the oposite way to your other boards ?. . . . connecting the two would then short them out ?
  Definately sounds like a job for the multimetre. . . if you open Brians instructions on your Ipad you can refer to them while using the danged thing !!   :thumbs

cheers

Matt

Hi Matt. Thank you for your confidence. At first, after the initial “ SNAFU”,with the three way point, once I had replaced it with another L/H point everything was okay. Then the short occurred . Now I am convinced that the short is on the â€œ Jumper “ between the Inglenook and the Fiddleyard, “ enter stage left Mr Multimeter “ . But, before all that happens? Another busy day Iies ahead . All the usual stuff,Hospital, GP, shopping . Best wishes Kevin 

This device will self destruct in 5…4…3…2…

Go on use…USE IT !  You know you want to   :thumbs

Cheers

Matt

Hi Nigel. You may have just noticed, that I haven’t managed to reduce the photo size/ pixels of the multimeter that I have just uploaded. But that is my multimeter. Best wishes Kevin 

I take it you didn't use the laptop then Kevin 

Hi Matt. Thank you for what? I will try to locate a short or short circuits. In the meantime I can’t make out what can be wrong with the wiring as it is the way that I have used before.  Best wishes Kevin 

Hi Matt.  You wouldn’t believe it! “ I don’t believe it “ but I forgot about the Laptop, I will have to get into it all over again. I will have to get used to using the Canon power shot, again. Best wishes Kevin 

:pathead :patheadWell done with posting the photo Kevin You now being able to post photos will greatly help people help you solve your problems you come across.
A nice little multimeter there you have it will aid you a great deal once you know a few basic ways to use it.

Brian

Thank you Brian,but, “ I could do better “ now that thanks to a gentleman of this Parish, has put my laptop back on its feet. Keep watching this space . Best wishes Kevin 

Hi Kevin,

Almost the same as mine.

Nigel

Hi Nigel. Thank you. If I can stay awake long enough I will have to try..  but before I get that far? Everything was okay until I laid the fresh copper clad sleepers. I have seen a plan today online, with the electrical connection going through the “ baseboard joint clamps” And save the bother of plugs and sockets?   Best wishes Kevin 

Hi Kevin,

Baseboard clamps? As in joining clamps? One either side? Bare metal? Oh yes, I can see some interesting scenarios.  Along the lines of "well I never", and "I don't believe it".  :lol: :lol: :lol: Metal locating dowels would be marginally better. Although power poles or molex type connectors would be a lot, lot better. I came across some 2 amp rated RCA type connectors recently (MF), flexible cord, cut in half, bare wires to the block terminals, works a treat with the NCE PowerCab system. Push/pull to connect/disconnect.

Copperclad. You did remember to cut an insulating groove across the copper and test for continuity? (Lack thereof that is).

Nigel

Hi Nigel.  Thank you for your reply. Power poles? yes i did purchase them in readiness, but, the crimping tool that I purchased was for the wrong type of connector. I also have reservations about using baseboard clamps for electrical connections. As for copper clad sleepers I have nearly cut all the way through them, everytime I go back after another short circuit, I have another hack at the sleepers.  Best wishes Kevin 

Hi Kevn,

No need to hack if you test with the multimeter (hint, hint). It is either insulated or conducting.

These are the cables I'm using at the moment (1 meter long).$3.33 each. Used as CCTV camera connectors.

Nigel