Author Topic: MODEL RAIL POWER SUPPLIES  (Read 2660 times)

Tom

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MODEL RAIL POWER SUPPLIES
« on: May 15, 2019, 08:23:43 PM »
I am considering going from a small layout which works fine with one PWR-56 to a larger one that may require multiple PWR-56 power supplies.

I have no experience with DCC other than to know that Ring modules work well with either PWR-56 or DCC power.

1) If multiple PWR-56 power supplies are going to be required, is each isolated electrically from each other or do they work together with no isolation?

2) Again, no experience with DCC: is there a point where buying a DCC power supply becomes more economical than multiple PWR-56 power supplies? 

Thanks to anyone who knows.

G8B4Life

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Re: MODEL RAIL POWER SUPPLIES
« Reply #1 on: May 16, 2019, 12:27:12 AM »
1) If multiple PWR-56 power supplies are going to be required, is each isolated electrically from each other or do they work together with no isolation?

Yes, the PWR-56's are isolated from each other (the track is gapped) when used in multiple, same as any other power supply.

Quote
2) Again, no experience with DCC: is there a point where buying a DCC power supply becomes more economical than multiple PWR-56 power supplies? 

Probably not, a single PWR-56 from pdc.ca is $89.00 (rrp $119.99), DCC "power supplies" seem to start at-discount at the same price as the PWR-56 rrp and go up from there.  It'll also be the same as using the PWR-56; if you need multiple PWR-56's you'll need to use multiple DCC power supplies, it wouldn't be a one-instead-of-many situation. Using DCC as the power supply you might need the DCC command station (and not just a cheap booster) as well and that'll add significantly to the cost of using DCC to power RailPro, an unnecessary cost if you'll never use DCC on the layout.

There is another method though it takes a bit more than just Plug 'n' Play and that's to use switched mode power supplies, these things can be had rather cheaply but you do need to wire them up yourself (usual disclaimer about wiring up 110/230v connections yourself applies).

Alan has a good bit on his blog about using them. http://www.lkorailroad.com/powering-the-lko-part-i/ and we have a couple of threads here on it as well.

- Tim

William Brillinger

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Re: MODEL RAIL POWER SUPPLIES
« Reply #2 on: May 16, 2019, 06:37:45 AM »
Don;t forget about the PWR-56's ability to act as a repeater. This is handy on larger layouts too.
- Bill Brillinger, RPUG Admin

Modeling the BNML in HO Scale, owner of Precision Design Co., and RailPro Dealer.


atsfguy

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Re: MODEL RAIL POWER SUPPLIES
« Reply #3 on: May 16, 2019, 02:23:16 PM »
 This is my usual stupid question, but at what main line length is it necessary to break the line into two or more sections?
 My “main line” will be about 100’ long, more or less in a semi-straight line. Will one pwr 56 be adequate or should I spend a bit of dinero for another to power the second half?
 I plan to place the ps at the half way point and fan out from there.
 As soon as my back is well I will place a few more modules in position, lay roadbed and track. I want to wire as I go so as to have some running room.
 As always, I appreciate any help that can be given.

Cecil
Cecil
ATSF

William Brillinger

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Re: MODEL RAIL POWER SUPPLIES
« Reply #4 on: May 16, 2019, 02:32:49 PM »
Quote
My “main line” will be about 100’ long, more or less in a semi-straight line. Will one pwr 56 be adequate or should I spend a bit of dinero for another to power the second half?

My Point to Point Main line run is longer than that and I only use 1 PWR-56. The important questions will be how many locos will be running at the same time and will it pass the coin test at the ends.

Since you have not laid the track yet, consider breaking the track into several blocks as you install it and then if you need to subdivide it later, you just have to cut the bus at your existing track breaks and install new power supplies as needed. This way you can start with 1 power supply and easily add more later without having to disturb the track.
- Bill Brillinger, RPUG Admin

Modeling the BNML in HO Scale, owner of Precision Design Co., and RailPro Dealer.


Alan

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Re: MODEL RAIL POWER SUPPLIES
« Reply #5 on: May 16, 2019, 07:32:04 PM »
I agree with Bill. The length of the layout is not the determining factor. The number of locomotives and other powered rolling stock in operation simultaneously is the determining factor.

The consideration of layout length is due to electrical resistance of the rails and your bus wiring. Heavy gauge wire for your bus eliminates this concern and is considerably less expensive than multiple power supplies. Use 12 gauge wire for your bus and there is no practical limit to layout length.

The repeater functionality is exclusive to RP power supplies. If your layout room contains a lot of significant size grounded metal structures (water heater, furnace, washer, dryer, etc.) or is separated by thick concrete walls then the repeater functionality may be of value. In clear space the HC and LMs have excellent range with no repeater necessary. My train room in the basement is 28x32 with stud and sheetrock walls separating it from the rest of the basement. I can operate from the opposite end of the basement, approx 75' away and through two walls, without repeater.
Alan

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When I was a kid... no wait, I still do that. HO, 28x32, double deck, 1969, RailPro