How much power?

[n2mopac]

This question is related to Propgator's post, but different nonetheless. I am building a 16'x17' N scale layout with 100' of mainline and 300' of total track (yards, industrial tracks, staging, etc.). I am powering this baby with Digitrax Empire Builder (5 amp). I will have a total of 12-15 locomotives on the layout, though a miximum of 6-8 running at any given time. My question is how many power boosters/districts do I need. I am sure this is too much for the single 5 amp booster included with the package. Is 2 enough? Is there a formula for the approximate length of track/number of locomotives you can run per amp of boostsr power? Help me out here folks. [8D]
Ron

[Anonymous]

I run 8 HO locos at once on aprox 80 foot mains with 250 feet total trach with just the 4 amp unit that came with my unit. They have no problems. I just ran a 14 ga copper wire bus under the layout and connect the track every 10 feet or so to it. Before I ran the bus the locos would slow down a little on the far side of the layout, but since the bus was installed no problems. These locos pull 10 to 15 cars per unit, so i really can't see you needing a booster on 6 N locos. I'm sure others will say you need a booster, but my experience is I can't see you needing one. FRED

[Anonymous]

Hi Fred,
Thanks for the info you gave Ron. I do believe I will continue on without a booster, until I have trouble. If it ain't broke, don't fix it.

Propgator

[ndbprr]

The one answer I don't see is in regard to districts. The more you have the easier it is going to be to find that pesky short circuit when it happens.

[Anonymous]

This is another question on this topic -- what is a "power district?? Is this like a DC "block" system?? Do you use rail insulators in power districts?? Thanks for your help!!

[Anonymous]

QUOTE: Originally posted by ndbprr

The one answer I don't see is in regard to districts. The more you have the easier it is going to be to find that pesky short circuit when it happens.

The only short I ever get is laying something metal on the track and that's not hard to find. What besides a loco or piece of metal on the track could cause a short? and why would I need the extra complexity of districts to find the problem? and what do districts even have to do with boosters, you can have districts without boosters? In my opinion districts went out with the DC and is just more Rue Goldberg in your system. FRED

[Anonymous]

QUOTE: Originally posted by RalphJenkins

This is another question on this topic -- what is a "power district?? Is this like a DC "block" system?? Do you use rail insulators in power districts?? Thanks for your help!!

In one sense a power district it is like a DC Block, but it is not used or wired like a DC Block.

The purpose of a power district is to isolate a section of track (both rails) from other parts of the railroad. If there is ever a short in this power district (such as from a derailment or the well documented issue with power routed turnouts), Only that power district will be shut down by the auto circuit breaker. The rest of the railroad in all other power districts will remain powered and running. Power districts can be created by wiring each (both rails) to different boosters, but that can get expensive. They can also be created by using a device such as the Digitrax PM42 (Power manager) or a Powershield from Tony's Train Xchange www.tonystrains.com (I'm sure there are other examples). This device is wired between a single booster and each power district. It is more sensitive to shorts than the booster, so it will trip (circuit breaker) before the booster trips, thus keeping the booster up and all other power districts functional.

And yes, a power district can also by used and an aid in finding shorts caused by wiring errors. You still have to keep track of "polarity" with DCC when wiring.

Dale B.

[Anonymous]

With 5 amps you will have definitely have enough power. Rather than power districts that strictly are separate power for each districts, you are better off to buy the PM42 which has four separate units in it which can either be for auto reversing or short protection. Instead divide your layout into short protected districts. Go to the Digitrax site and look it up.

So with one PM42 you could divide your layout into 4 distinct sections that would have short protection. So if one section goes down, the other three sections are still functional. The length of track and total track is very similar to my situation. Probably the most engines run at one time on my layout will be 6 to 8 engines. 5 Amps will serve you well. Grab an MR and look at some N scale engines reviewed, you will see the average draw in N scale is around .3 amps so multiply that by 8 and you will see you are well below 5 amps.

Note: I changed the name of the detection unit as I was asleep at the switch and wrote the wrong name in.

[Anonymous]

Sounds like a high tech (and expensive) way to fix a low tech problem. Fix your track and locos to prevent derailments and shorts. Buy an expensive item to help you keep track of how you wire your system when you build it? Even if you have a frog problem one of two things happen, the system stops and you find the loco in the turnout that caused the problem and fix it, or it shuts down and monentum carrys it through and the power comes back on and you still fix it. I understand that some hobbyist like to do high tech wiring and super dcc systems, I like doing scenery. I don't tell everyone who asks that to do it right they need to make their own trees and scratch all their buildings, so why are you all professing that we need to do your high tech wiring methods? FRED

[n2mopac]

I am using Peco insulfrog turnouts and I like the idea of power districts, especially if I don't have to buy expensive boosters for each one. The wiring for the Power Manager or the RP42 doesn't sound too complex. I will look into the cost of these. I have to admit that wiring is my least favorite and least skilled area of this hobby, but I had planned all along to divide the layout into at least 3 power districts for both diagnostic and maint. purposes (plus I thought I would need at least one booster). I am happy to hear that my 5 amp booster will be enough alone. The less $$$ I have to sink into electronics the better (the more I can spend on rolling stock, scratch building supplies, etc.). Thanks again everyone.
Ron

[Anonymous]

Hope you saw my ammended post, if you look for the RP42 you won't find it, it doesn't exist, instead PM42. I had just finished re-reading a chapter in one of the DCC books and RP is "recommended practices." Hope you see this.

[n2mopac]

QUOTE: Originally posted by rsn48

Hope you saw my ammended post, if you look for the RP42 you won't find it, it doesn't exist, instead PM42. I had just finished re-reading a chapter in one of the DCC books and RP is "recommended practices." Hope you see this.

Thanks for the clarification. I had already figured it out when I went to look it up on Digitrax web site. Thanks again for the help.
Ron