Wiring lights and accessories

Started by andy1721, April 25, 2011, 09:08:59 PM

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andy1721

I'm new to trains and I'm at the point on my train table that I want to wire lights under the table.  Anyone have a suggestion as to a good source for instruction and what electrical parts that I'll need.  How to I connect all the lighted pieces to one power source, but still have control through switches to turn some on and some off.  I don't have DCC.  Help please

jonathan

Andy,

I run DC on my home layout.  I use an older DC power pack to run my street and signal lighting.

You can use either the DC or AC output on an old power pack.  I use the DC side so I can use the throttle to control the brightness.

Run two wires the entire length of your layout.  A thicker gage is better.  These two wires are connected to the outputs on your power pack.  This is your "bus" wiring.

Then you can tap into these wires to connect your layout lights.  This is connecting in parallel.  The number of lights you can run on on this system depends on the amp output of the power pack.    Each bulb will draw a certain amount of milli-amps.  I can run about 30 bulbs on my system.  I am nearing the limit and will have to put in a second power pack for additional lighting.

I recently picked up an old Bachmann power pack at an LHS for $5.  This will drive my next bank of lights.

There are other methods, but this is what I use.  Just to give you an idea...

Regards,

Jonathan

Doneldon

Andy-

Jonathan's suggestion that you run a power buss around your layout to feed structure/scenery lights is an excellent one. I'm guessing that by "thicker gauge" he means 16 or even 14 gauge wire for the buss(es). You can use much smaller wire, even 22 - 26 gauge, for the short runs up to the individual lights. The larger wire will allow the current to pass without sapping a lot of the energy just moving the electricity. You'll find that stranded wire is much easier to use than solid wire although it does cost more. I run solid buss wires and use smaller, more flexible stranded wire from the busses to the lights. I do the same with track feeders.

You can run a lot more lights and have easier wiring if you use LEDs. You'll need a 4.0 - 4.5 watt source and there's a good chance you have an unused, serviceable wall wart around your house which will fit the bill. You can use a higher wattage transformer but you'll have to putz with resistors if you do so. The greatest advantages of LED are that they make very little heat compared to incandescents and they can be much cheaper to acquire. Less heat means you won't get melty spots in your structures and scenery, or glue that dries out and lets go before its normal time. Cheap acquisition means buying LED Christmas lights on close out, using Harbor Freight coupons for free flashlights and such like. Regular LED prices are quite steep, as are incandescents, but there are more sources of cheapie LEDs if you watch for them.


I notice, though, that you want to be able to turn your lights on and off in groups. In that case, you'll need a power buss for each group of lights. You can still tap one power source, if it's big enough to handle all of your needs at one time, by running leads to each light group switch, and then layout power busses from those. This is essentially the way your home is wired; one circuit starts in the service entrance and you turn various lights on with switches on that circuit. Indeed, the service entrance itself even uses the same principle; you have the electric company's input wiring which your service entrance (fuse or circuit breaker box) divides into many circuits which can be independently used or not. Notice, too, that your service entrance is sized to accommodate all of your home's needs, just as your power source must be able to supply everything for those times when you want all of your lights or features operating.

Good luck with your project, but I'm sure you'll do fine with it.
                                                                                            -- D

BradKT

I asked a similar question on one of my threads on this site some time ago and Jim Banner told me that the wires that I use for my "bus" line under the layout that I run the street lights to should be bare copper wires.

Jerrys HO

Brad, Jim said that is what he would or does use. It is always personal preference when modeling. A bare wire is very acceptable as long as it is secured underneath where as nothing can snag on it or ground it out. If you plan on using the underneath to store your lawnmower,ladders, etc. NO it probably would not be in your best interest to go bare. Insulated is just as good.

Jim Banner

If you are concerned about snagging the wires or accidentally shorting the supply and return wires, then by all means use insulated supply wires but still use a heavy, bare wire for the common return.  The advantage is that it is easier to connect to the bare wire, especially when it is the return for all the lights, turnouts, animation etc. and has lots of feeder wires connected to it.  If all your other wires are insulated, then it is impossible to accidentally short them to the return wire.  If you are concerned about "grounding out" that single bare wire, you can forestall any possibility of problems by purposely grounding it to an actual ground like a water pipe.  Personal preference, definitely.  But it is a good system that works well.

Jim
Growing older is mandatory but growing up is optional.

andy1721

Quote from: Jim Banner on May 01, 2011, 02:04:41 AM
If you are concerned about snagging the wires or accidentally shorting the supply and return wires, then by all means use insulated supply wires but still use a heavy, bare wire for the common return.  The advantage is that it is easier to connect to the bare wire, especially when it is the return for all the lights, turnouts, animation etc. and has lots of feeder wires connected to it.  If all your other wires are insulated, then it is impossible to accidentally short them to the return wire.  If you are concerned about "grounding out" that single bare wire, you can forestall any possibility of problems by purposely grounding it to an actual ground like a water pipe.  Personal preference, definitely.  But it is a good system that works well.

Jim