News:

Please read the Forum Code of Conduct   >>Click Here <<

Main Menu

need power for ho train set

Started by tee, October 19, 2009, 12:57:08 PM

Previous topic - Next topic

tee

hi   i have 250ft of track and 60 lights to power .the set is one train going one way  i  have lights wired 8 per board so i can run light seperate      i can power 8 lights with one power pack that came with train any more and they shut off     no switch rails and only one train

rich1998

not sure i understand. your message says what you are doing right now so you must have a power pack.
lex

Jim Banner

A typical power pack that comes with a train set is rated around 8 VA at 16 volts.  That works out to 1/2 amp.  If you can run 8 lamps on the power pack your have, then they are probably drawing 60 to 65 milliamps each.  For 60 such lights, you would need about 3.6 to 3.8 amps.  An ideal solution would be a 12 or 16 volt transformer rated at 4 amps but a more practical one may be to use four 1 amp wall wart power supplies (ac or dc, the lamps don't care.)  Use the power pack that came with the train to run just the train.

For best lamp performance, use the lowest voltage that will give you adequate light.  If your lamps are rated 12 volts and have a service life of 1000 hours at that voltage, their service life will be less than 24 hours at 16 volts.

Wall wart power supplies (the ones with a big fat plug on one end of a wire) are available used or surplus for a buck or two.  At garage sales, they are often even cheaper.

Jim
Growing older is mandatory but growing up is optional.

tee


Running Bear

I use a Digitrax Zephyr DCC system to run my trains. I use an old AT type computer power supply to power the structure lights. On my last layout it was pulling 98 lights without a problem. On my current layout it's pulling only half that number, but I still have a number of structures to put lights in.
Running Bear

Jim Banner

Using computer power supplies is cost effective.  I usually do a couple of internal modifications, but you can get away without them.  One thing you CANNOT get away without is fuses.  Imagine all the heat from a 150 watt soldering iron concentrated at one small point.  That is what you can get with an arcing short with a 5 volt, 30 amp output.  This can ignite a variety of things found under a model railroad in seconds.  My recommendation is to fuse every wire you use (except the black return wires) with a fuse no larger than 5 amps.  If you wanted to use all 30 amps of the 5 volt output, that would be 6 fuses, each fed by one of the many 5 volt wires.  Same with the other voltage outputs.  The fuses will protect the wiring in case of a short.  Automotive in line fuse holders will do the job and are much cheaper than your house.

There are a lot of cheap, 50 or 100 or 200 to a string miniature Christmas lights on the market, or there will be very shortly.  The bulbs in these strings are usually rated 2.5 volts, 160 milliamps.  You can run them in series pairs on the 5 volt output of a computer power supply.  A 30 amp output can drive 187 such pairs for a total of 374 bulbs.  For longer life and a pleasant glow, try the same bulbs in series triplets.  Now you are up to about 560 bulbs, with an average life of about 40,000 hours (compared to a normal bulb life of 200 hours.)

Cheap lights, a cheap or even free power supply, but Don't forget the fuses!!

Jim 
Growing older is mandatory but growing up is optional.