Purpose of the Recommended Practice
The original NTRAK standard specifying 18 gauge stranded "zip wire"
for main track busses, 16 gauge for the "White" coded DC power bus and
Cinch-Jones 302 Series two pin connectors remains the "standard wiring"
for NTRAK modules. For individuals or clubs looking for wiring with less
voltage loss, the following are "Recommended Practices" (RPs) which should
be considered for new construction, refurbishing of existing modules and
for modules used primarily with Digital Command Control (DCC). The goal of
this RP is to provide a common approach to reducing wire and connector
losses and to increase the number of power feeds to the tracks.
RP -
Track Bus
Each
NTRAK track (red, yellow, blue, green, etc.) shall have a continuous
(unbroken) electrical bus running the length of the module. The bus shall be
12-gauge stranded copper zip wire (red/black zip wire, outdoor low-voltage
lighting wire or speaker wire, or equivalent). This wire has a thin section
between the two wires and can be "zipped" apart. One side of the covering
has a rib molded along its length; connect the ribbed wire (or red wire in
the case of red/black zip wire) to the front rail of the associated track
and to the red or colored connector at the end of each bus.
The length of the bus wire is the length of the module plus 12" at each end.
RP-
Connectors
Each
bus will be connected to other modules using Anderson PP30 30 Amp Powerpole
connectors at each end of the module, as follows:
 |
| Module End |
Stacking |
Configuration |
| Right |
Vertical |
Red over Black |
Left
|
Vertical
|
Black over Red
|
|
 |
| Left End |
|
Right End |
RP -
Color Coding
If
red/black pairs of Powerpole connectors are used, they shall be color coded
with tape or paint in accordance with NTRAK color standards, as shown in the
photo and per the 2nd column of the color chart below. Alternately, appropriate colored Powerpole housings may be used as shown in the 3rd column
below.
RP
- Track Feeders
Each track shall be connected to its corresponding electrical bus by pairs
of feeder wires located every two feet beginning one foot from the module
end. One or two foot long modules require only one feeder per track located
at the center of the module. Solid core 18–22 gauge insulated wire shall be
soldered to the outside or bottom of the rails and to the electrical bus.
Feeder wires should be kept as short as possible.
Alternatively, the track feeder may be soldered to the rails as described in
the paragraph above and connected to a terminal strip. The unbroken track
bus shall connect to the terminal strip by wrapping the electrical bus
around one screw or by a drop wire soldered to the bus which is then
terminated on the terminal strip for
distribution. This will permit correcting any wiring errors easily. Screw
terminals shall be securely tightened and checked for tightness before each
train show.
Note 1: Turnouts shall have feeders installed at both ends for all mainline
tracks, with appropriate insulated joiners/gaps at the frog end.
Note 2: If unsoldered rail joints are used at any location on the mainline
tracks, a feeder shall be present on both sides of the unsoldered joints.
RP - Private Tracks
If the track(s) will only be powered from the connecting NTRAK track, then
simply connect a pair of feeders from the connecting track bus to the
private track. (If the turnouts are Electrofrog be sure to gap both (2) frog
rails at the frog end of the turnout.)
If it is desired to provide alternate local power for private tracks (DC
power pack or separate DCC booster), use a DPDT switch. This is, in effect,
two cab wiring with the connecting NTRAK track as the primary cab and the
local DC power pack or DCC booster as the “local” cab.
RP - White Wire
The White Wire is NOT required for DCC operation; however, for compatibility
with existing NTRAK modules the white wire must be included in the module
wiring. While the NTRAK Electrical Standard specifies 16-gauge stranded "zip
cord" with Cinch-Jones connectors on each end this Recommended
Practice recommends the same 12-gauge wire used for the Electrical
Bus.
For
the White Wire, Powerpole connectors at both module ends shall be
arranged horizontally, red (DC +) on the left and black (DC -) on the right, as
shown below.
Use of the White Wire for private track powering or accessories is
prohibited.
The use of the White Wire for 16VAC supply to DCC Boosters is not
permitted for safety reasons. Boosters shall be powered with a
dedicated 120V to 16VAC power supply for each Booster.
RP - Adapter Cables
Since the use of Anderson Powerpole connectors is a Recommended
Practice rather than the NTRAK Electrical Standard, adapters from
Powerpole connectors to Cinch- Jones connectors shall be provided
for modules (or module sets) wired with Powerpole connectors. See
photo in next column.
16-gauge stranded wire should be used for the adapters with a
maximum length of six
(6) inches. At least one of the connections to the Cinch-Jones wire
terminals should be insulated using either electrical tape or
heat-shrink tubing to ensure no stray wires inside the shell can
touch and cause a short.
Color-coding should be applied to the adapter cables using tape,
paint, or appropriately colored Powerpole housings in place of the red
housing.
Standard - 120VAC Wiring
This represents no change from the current standard. A UL/CSA
approved heavy duty, multi-outlet, extension unit with a grounded
(three wire) power cord, 14- gauge wire, 15-Amp capacity is required
for each module. The outlets should be at the left end of the module
and the plug at the right end. Use Stanley 1-1/4" Safety Cup Hooks
#752976 or equivalent to retain and anchor the cord to the underside
of the module. This unit shall be removable to meet safety codes.
120VAC wiring is subject to inspection by safety officials at public
gatherings.
Where to get Powerpole Connectors
Powerpole
connector pairs are available through the NTRAK Model Railroading
Society's business office. An online Order Form and pricing is
available at
http://www.ntrak.org/order_form.htm. All sets include an
instruction sheet.
Set “Red/Black” has 10 Red/Black housing pairs and two extra
contacts.
Set “NTRAK Colors” has housings with molded in colors for Red,
Yellow, Blue and White. Black is used as the other pair color. Two
extra contacts are included in the set.
Two pair sets are available for the Mountain Div track
(Green/Black); Front passing track (Orange/Black); Alternate
Branchline (Blue/Yellow). These sets include an extra contact.
Other custom color sets will be made up on request at the two pair
price.
Note: NTRAK pricing includes shipping cost and there is no minimum
order amount. Other sources often have extra shipping costs or an
order minimum.
Some other sources are the following “on line” electronic supply
firms:
Cablexperts at
http://www.cablexperts.com/cfdocs/cat.cfm?ItemGroup=9&itmsub=0&bskt=0&USA_ship=1&c=0
Connex Electronics at
http://www.connex-electronics.com/html/products/anderson/powerpole/pp_main.html
Hometek at
http://www.cheapham.com/coax-wire.html
Powerwerx at
http://www.powerwerx.com
Powerpoles are also carried by major industrial electronics
distributors, including
Newark InOne (http://www.newark.com)
and Allied Electronics (http://www.alliedelec.com).
Since the 30A Powerpoles are also used in the R/C model aircraft
hobby they may be available at R/C oriented hobby shops. They may be
known as SB connectors or Sermos connectors in these shops.
Material for this RP was furnished by Doug
Stuard and John Wallis.
November 2005
© NTRAK Modular Railroading Society, Inc., 1150
Wine Country Place, Templeton, CA 93465
NTRAK Order Dept., c/o Dave Porter, PO Box 3618,
Parker CO 80134, website at
http://www.ntrak.org
|
NTRAK Modular Railroading Society, Inc