I purchased a Powershield circuit breaker from Tony’s Train Exchange, the type with holes in which to solder your input/output wires. I’ve soldered on rail joiners and trackfeeder wires but I’ve never soldered anything to a circuit board. The holes (see photo below) marked dcc1 and dcc2 are for the wires leading to the power supply…
I’m using small door bell wire and it’s a bit smaller than these holes. My questions are, since I’ve not soldered to anything like this, :
1- Is this size wire ok or do I need to get a larger wire?
2- Do I NOT touch the board with the soldering iron but instead heat the solder and let it drop on the wire/hole, thus soldering the connection?
Any suggestions and tips on how to go about this without doing damage to the board is appreciated!
I am not the greatest solderer int he world but I would thing you will need to heat the board enough to let the solder flow into the circut board. do it fast as not th damage the componets of the board. Some of the others will probley have better suggestions. Mike
Ok…here is what you should do for a good solder joint. (I solder all day long for my work - Engineering Tech for a DC Supply Company - so here is what I learned in doing through hole joints).
Prep your wire that your going to install. By this I mean ‘tin’ the wire. So you will need to strip your wire, use your soldering iron and solder - holding both near the top of the exposed wire. Get heat action started to where the solder is flowing and follow down the wire. It doesn’t have to be perfect, but you should see a bit of solder holding on the wire itself.
Install your wire into the hole you will be soldering to, usually with the wire starting on the component side (side with all of the parts). This isn’t a must…you can do from the solder side as well.
With the wire installed in the hole, try to heat your wire AND the barrel (metal part around the hole) at the same time. Touch your solder to the tip of your iron (where the contact points have been made between the metal and wire). Put enough solder on so that you have a nice pyramid or triangle look to the joint. If you have it looking like it is almost like a ball…you have gone too far and could have an unreliable joint.
Trim of the excess wire on the bottom (solder side) of the board.
Hope this helps you out. It’s hard to explain but hopefully you can follow it through.
Craig provides excellent advice. The only thing I would add is that you want to do this in a quick motion. Sometimes there can be other components on the board that can be affected by the soldering process. Look for example at the JP2B holes at the bottom of the picture. You can see that there are some small surface mount resistors very close to the holes. Heat will quickly travel down the tracks of the circuit board to these components and you can cause them to become unsoldered and come off the board. So a nice hot iron applied quickly is important.
Great! Thanks for the detailed instructions! I have one more question and it deals with somehow mounting the board under my layout. There are two holes in the center area of the board marked MTH and they don’t seem to be electrically connected to any other parts on the board. I’m thinking about small screws through these holes. Good idea or bad one?
I would suggest you get some soldering flux from your local electronics store.
After you strip the ends of the wire remember to twist the strands tightly so there are no loose strands that could cause a short.
To tin the wires, put a little bit of flux on the wire, (a little goes a long way), heat the wire for a couple of seconds and then feed the solder to the wire until it’s shiney silver. You don’t want a big blob of solder on the wire, just a coating. If you get too much solder on the wire, reheat it and give it little flick to shake off the excess. Trim the tinned wire to about a 1/4".
Insert the wire from the component side. On the foil side you’ll see the wire coming through a hole in the foil pad. Put a little flux at the joint, then touch the joint with the tip of the iron for a couple of seconds and then feed a bit of solder until the pad has built up a little cone of solder around the wire, (about 1/8"). Each joint should only take about 5-7 seconds.
Two last points:
Don’t use anything bigger than a 30-40 watt soldering iron. A 15watt iron is actually best for circuit board work.
Make sure the tip of the iron is clean and shiney. Use a slightly damp sponge to wipe it clean. Radio Shack has some tip cleaner, you just dip the tip in it for a few seconds and then wipe it clean with the sponge.
The holes marked MTH are indeed moutning holes - there are no circuit traces around these. You need a standoff of some sort though, you don’t wnat to screw the board tight against a block of wood. I don’t have a Powershield so I can’t tell how big the holes are at the MTH locations, but they MIGHT fit nicely with computer parts - you can pick up standoffs and matching screws at any place that sells computer parts if the holes are indeed the right size. Hopefuly they are - because I have a large supply of these items from building many computers over the years.
As for the wire, small wire isn’t bad, just keep them short and your best bet it to run them to terminal strips to which you can connect the heavier bus wires to and from your layout. The holes in the PS can handle maybe #18 wire, possibly #16 tops. Short lengths of smaller wire are not a problem though. Soldering these is where the slightly bigger iron comes in handy - it’s a function of the mass you need to heat. Those tiny 15 watt irons are great for electronic components, not a lot of area to heat and the low power protects the delicate components. With a large solder pad and a big piece of wire there’s more to heat up. Like soldering track, that low power tool will take way too long to heat the joint area and be more likely to cause damage than a slightly heavier tool. The only danger in soldering the power leads here is maintaining the heat too long and lifting the trace from the board. Going really overboard and you MIGHT desolder adjacent components - but that REALLY takes some ‘skill’ (or rather complete lack thereof) to accomplish - so don’t be afraid. Like everything else, the right tool makes a huge difference. Someone with a lot of experience at coldering electronics may very well make due with a single medium-size tool - I for one would not really worry if I had to use my 40 watter to build a circuit board - it’s just that you are far less likely to cause damage by using the appropriate sized tool for the job. If you have to
I use the hex nut mounting screw for mounting computer boards down to a case… I had a few extra laying around and it works great. Oh, and you may want to solder an LED so you can tell when the PS1 is tripped (I have a PS2 and I LOVE it). As well, I would solder a momentary switch as per the directions that lets you reset the breaker… In regards to larger wire, it depends on the lenght you are going with it (under 2 feet, likely won’t matter) as well as the amperage. I used 14 guage for short runs between components and 10-12 gauge for my power bus under the layout… just my 2 cents! Enjoy.
Well, I held my breath and did you guys said and soldered the sucker. I used a 30 watt iron and everything seems to be ok and working fine… except for … onnnnnne itty bitty problem. The board is the type you use for 2 power districts which I have. If you have a short in one district the other keeps going.
Mine don’t.
Hmmmmm… gotta figure that one out. Or… better yet… call Tony’s Monday and see if they know. I’m betting they do.
NOW, all I gotta do is figure out what a ‘stand out’ is. Maybe it’s a small hollow, short tube that you put on the back of the board to keep from drawing it in too far with the screw when mounting.
Hey, between all of us we got it wired and it’s working!
Hey Brian, did you have to solder any jumpers on yours? I have the PS2 and when I get a short it still shuts the whole layout down, even the yard which is on a separate main buss.
Go to a computer repair shop an ask for some stand-offs, plastic ones, if they have them. If not, the metal ones will work. You have to get the screws also for the metal ones. The plastic ones just clip into the holes.
For standoffs, just cut off some 1/4" or so lengths of hollow styrene tubing that’s big enough to pass your mounting screw through. If you’ve got styrene tubing lying around for scratchbuilding, the standoffs become cheaper than borscht.
Thanks for the tips on the standoffs. I have an old computer around here somewhere… bottom of a closet, I think. I’ll take a look and see if it has any in it. If not, I’ll make some or get them at a computer store.
Hmmm… dunno yet actually…it should not. I don’t have my second district yet wired [:)] I just followed the directions… I think I did solder some jumpers to increase the amperage to trip, etc. as per the directions… But each district should be separate. Email Tony if you have questions…(tonystrains is where you got it, right?). He is VERY helpful.
Jarell, you need to adjust your Zephyr so it takes longer to trip. Change OpSw 18 to Closed. Push PROG, then push Switch, then select 18, and hit Closed. This might work. I noticed Tony’s web site mentions a lower power mode - they might be able to tell you how to do this yourself. The default PowerShield trip current is 3.8 amps - that’s more than the Zephyr can put out. But slowing down the Zephyr might work.
