Do you guys solder the wires before putting them inside your terminal strip or distribution board?, or do you think its fine to just put the strands in with out tinting wire first?.
Thank you.
Yes
As I understand it you should not tin wire before putting it into any screw-type terminal. It is better to leave the strands unsoldered and screw straight onto the bare wires.
The reason for this is that compression or ageing of the solder on the tinned wires can cause conduction problems and possible failure of the join.
Neil
My experience has been the screws splay multicore wires and cause intermittent contact.
As a qualified electrician, I wouldn't ever recommend using tinned cable ends in screw connectors.
I frequently get called to jobs where there's a flickering light, hot switch, burning smell from a socket. It's invariably where the multi strand cable has been tinned. Because tinning creates a solid 'lump' screws have a habit of loosening. This doesn't tend to happen with loose strands.
Quote from: Bealman on January 25, 2024, 08:09:35 AMMy experience has been the screws splay multicore wires and cause intermittent contact.
George, I suspect you're having this trouble because there's not enough wire to adequately fill the connector. Try doubling over, or quadrupling over to fill the connector better.
Tinned ends do work fine in sprung, push fit connectors as there's the constant pressure from the spring.
Quote from: emjaybee on January 25, 2024, 08:21:41 AMAs a qualified electrician, I wouldn't ever recommend using tinned cable ends in screw connectors.
I frequently get called to jobs where there's a flickering light, hot switch, burning smell from a socket. It's invariably where the multi strand cable has been tinned. Because tinning creates a solid 'lump' screws have a habit of loosening. This doesn't tend to happen with loose strands.
Also, even if the screw doesn't loosen, the solder lump (or even lightly tinned wire) is harder than untinned stranded wire so the screw can't bite/crush into it so well and can reduce the effective contact area.
As is always the case, different philosophies, which really don't help the op get an answer.
I'll modify my post... I DO have connections in choc blocks which have not been soldered, but the sheer age of the layout is making them problematic.
Some help, I am! ;)
The best way to use screw terminals is to use bootlace ferrules on the ends of the wire being terminated.
Second best is multi-strand wire used bare.
Third best is single core or soldered multi-strand.
All will work for a model railway. More importantly is matching the size of the screw terminal to the wire size so a decent clamp under the screw is achieved.
The next question, if using unsoldered/uncrimped multi-strand wire do you twist it before putting it in the screw terminal.
Steven B
I always did!
Quote from: Bealman on January 25, 2024, 08:44:21 AMAs is always the case, different philosophies, which really don't help the op get an answer.
I'll modify my post... I DO have connections in choc blocks which have not been soldered, but the sheer age of the layout is making them problematic.
Some help, I am! ;)
Possibly oxidisation of the copper George. I realise that the task is onerous, but I'd suggest undoing connections, cleaning ends, trimming ends, rearranging ends, then remaking connection.
Quote from: Steven B on January 25, 2024, 09:00:20 AMThe best way to use screw terminals is to use bootlace ferrules on the ends of the wire being terminated.
Second best is multi-strand wire used bare.
Third best is single core or soldered multi-strand.
All will work for a model railway. More importantly is matching the size of the screw terminal to the wire size so a decent clamp under the screw is achieved.
The next question, if using unsoldered/uncrimped multi-strand wire do you twist it before putting it in the screw terminal.
Steven B
Sorry.
I'd cut any bootlace ferrules off, remake with bare strand. They suffer the same problem as tinned ends, they have a propensity to work loose over time.
I tend to twist loose strands, it makes it easier to get them into a connector and also increases the contact area as loose strands don't get 'pushed' out to the sides away from the screw.
I see, very helpful information every one, so based on every ones information i will put the stranded wire type of wire i have in to my distribution board that is a screw type one, with out soldering/tinning it. But the question is what steven said, should i have the wires twisted or not. EDIT - I assume having it flat and not twisted would be best
EDIT - im using multi strand wire
Twist it.
Better connection.
I know the industry best practice says not to tin the wires but with the small gauge equipment wire on layouts I have always twisted and tinned first and I prefer it. Mains wiring I leave as bare twisted ends.
I have used ferrules on occasion, but often my box of ferrules has vanished when I need them!
Thanks Ntp and Emjay!!.
One last question - Is it ok to leave the wire that is soldered to the rails exposed a bit or should it be covered with some thing, the bare wire is making contact with the foam trackbed and the wood of baseboard it never occurred to me that maybe they shouldn't be doing that.
Thank you very much!!!!!!!!!
Quote from: ntpntpntp on January 25, 2024, 09:40:12 AMI have used ferrules on occasion, but often my box of ferrules has vanished when I need them!
Aha, you have a tools/materials store just like mine :smiley-laughing:
Trouble is, I find that if I have a tidy up my chances of finding what I want decrease even more.
@Grassyfield no problem to leave a bit of bare wire as long as it doesn't touch another wire. foam and wood are insulators (generally. If they get very wet that can cause problems)
Nah it's not touching any thing just the foam of the trackbed and tiny bit of the wood of the baseboard. I have to wait till tomorrow to order my Decoder then im finally going to hopefully see my class 26 running!!!!! :claphappy: :claphappy:
Thanks Buddy!!!!
Quote from: emjaybee on January 25, 2024, 09:17:32 AMI'd cut any bootlace ferrules off, remake with bare strand. They suffer the same problem as tinned ends, they have a propensity to work loose over time.
I find it easier to capture all the strands of a multi-strand wire in a bootlace ferrule than doing capturing all the strands under the screw of a terminal block - particularly when installing under a baseboard.
The added volume of the ferrule also helps fill the void within the terminal block (which should be as full as possible).
Ferrules are also handy if you're likely to need to remove the wire from the terminal block on a semi-regular basis as they're more robust than a twist of wire which eventually will get crushed and mangled.
I've used all three methods without major problems (other than needing to tighten screw terminals occasionally).
Steven B
If it's a dcc layout then avoid using screw terminals completely for dcc signal wiring. Ideally, solder droppers directly to the bus wire. If you need to use terminal strips then solder tag strips are best - and it sounds like you are happy with soldering. If you want to avoid soldering and must use terminal strips then Wago connectors are much better than screw terminals (and easier).
Every screw terminal joint adds to the impedance of the wiring and it will get worse over time. As the copper compresses the connection becomes looser and the copper will oxidize causing the impedance to increase further. It's only a small difference but if you're starting from scratch then every little bit of good practice can contribute to high quality problem free dcc wiring in the future.
Quote from: Steven B on January 25, 2024, 11:55:30 AMQuote from: emjaybee on January 25, 2024, 09:17:32 AMI'd cut any bootlace ferrules off, remake with bare strand. They suffer the same problem as tinned ends, they have a propensity to work loose over time.
I find it easier to capture all the strands of a multi-strand wire in a bootlace ferrule than doing capturing all the strands under the screw of a terminal block - particularly when installing under a baseboard.
In industrial control panels, we use bootlace ferrules or other type of crimp-on ends, but they are terminated in proper terminals (not choc-block), that have self-locking mechanisms to stop the screw working loose.
Terminals with spring contacts (whether just sprung or lever-locked) are good for maintaining contact pressure, without having to worry about "creep". Indeed, they are the required way to install mains wiring, where a junction box will be inaccessible in the future and maintenance will not be possible.