All the below is non DCC.
Well I've aquired another controller that is completely seporate from
the other. Please see the crude drawing below of a track layout. It's
not my track but it'll help me understand more of someone can guide
So the outer loop is controlled by controller A and the innner by
controller B. When the 2 points at the top are "straight" I can use
both controllers at the same time with a train on each loop right?
Obviously if I want to move the inner train to the outer loop I'd have
to open the points. If I put the original loop A train in the siding
and isolate it I assume I can't just then turn off controller B, open
the points at the top and guide out loop B train using controller A?
This would mean both controllers are connected even though one is
If that's not possible where do I have to put the isolating switches?
and would I have to guide it out using one controller and then switch
to the other once I hit the isolating swtich?
I hope all this makes sense...
The Zero ST
To begin with, I strongly urge you to connect with other modellers or a
club near you, and get some face-to-face advice. Trying to explain this
stuff without sketches is dam' difficult. Bring a pad of paper with you,
as there will be lots of drawing and sketching! ;-) You should, I think,
also invest in a book about electrics and model railways.
As drawn, the crossover and a section of track on each oval must be
isolated from the rest of the layout, and selectable by either
controller. But you'll also need to select either oval by either
First and foremost, always think "controller = train", never "controller
= track". IOW, arrange things so that any section of track can be
connected to and controlled by any controller (in your case, two.) Use a
double throw switch (1) to connect each section to either controller.
Second, operating trains on the layout as drawn. Yes, parking one train
in the siding while the other crosses from the inner to the outer oval
(loop) will work (ignore the electrics for the moment). However, you
will have no way of getting the parked train into the inner oval, and to
get the other train back onto the inner oval will require backing up.
IOW, the layout as sketched is really a "one engine in steam" line, and
would need only one controller. If you put in another crossover between
the two ovals, facing the other way, then a train can cross from inner
to outer and back again without backing up, and vice versa.
Third, operating two trains on a simple layout: a there should be an
isolated passing loop on each oval (two on each oval would be better
yet.) Then you can park a train on the main or in the passing loop while
the other does its thing. The siding would not be needed, but you can of
course have as many sidings as you like for other (operational)
The electrics for running two trains are rather complicated, even for
this simple layout. Read on. ;-)
Fourth, the electrics: As mentioned above, you will need a crossover
section that covers _both_ ovals. The scheme described in point 3 (with
a passing loop) will require four or five electrical sections on each
oval, plus a common one for the crossover: 1A, the passing loop, 2A, the
mainline parallel to passing loop, 3AB the section with the crossover,
and 4A the rest of the oval (and 5A, depending on where the passing loop
and crossover are relative to each other.) A second crossover would
require even more electrical sections.
You'll need 1B, 2B, etc on the other oval, too. Sidings such as you have
drawn should also be isolated, and thus each would be an additional
And we're not finished yet.... ;-)
Whatever operating scheme you devise, on any layout, collisions are
possible. You avoid this by
A) adding control sections (= ones not required for electrical reasons
B) wiring and switching the sections in such a way that connecting one
to controller A will disconnect it from B, and vice versa (use double
throw switches and common earth wiring for this, or you'll need more
complicated switches and more wire); and
C) wiring the layout so that switching a section to A will disconnect
both the sections in front and behind the train from B (thus protecting
the train in prototypical fashion.) Double pole switches are needed for
this to work.
But judicious use of control sections and signal cabins (with signal men
to operate them) will prevent collisions. This also means that you may
need at least one other person to run trains, which makes for a much
more sociable time. ;-)
As you can see, even a simple layout like the one drawn and amended by
me requires a lot of switches, wire, and sometimes knotty logic to set
up for DC (direct current) operation. That's why DCC was invented. ;-)
And we haven't even touched on wiring up the turnouts (which can be done
so that the turnouts control some of the sections).
(1) For switches:
Pole = electrical connection.
Throw = connection made or unmade.
EG, a single pole, single throw switch connects one circuit (this is the
on-off kind you turn your lights on and off with.)
EG, a double throw switch connects with one or the other of two
circuits. It's best for it to be "centre off", ie, the positions are
"on-off-on." On many controllers, this is built into the speed control knob.
I remember how confused I was when wanted 4 controllers to control a number
of lines. Drew lots of curious circuit diagrams ....then realised the basic
concept is each track wants one and only one connection at all times,
whereas controllers can have one or multiple at any time.
So first isolate the loops with one set of plastic joiners connecting track
between the loops.
For first loop connect to output of double pole, double throw switch.
For 2nd loop connect to output of a different double pole, double throw
Connect first controller output to one input of both double pole double
Connect 2nd controller output to other input of both double pole double
throw (DPDT) switches.
Now as to 2 engines running - assumes you have one controller (A) switched
to inner via DPDT switch and one to outer (B) via other DPDT switch..
So to move engine from inner to outer :-
Move engine of outer to siding.
Set outer DPDT switch from controller B to controller A - now controller A
runs both loops.
Engine runs from inner to outer, still under control from A
You can now continue to use controller A on both loops, OR
Set controller B to same speed as controller A.
Set outer DPDT switch from controller A back to controller B.
You are back where started, with controller A on inner and controller B on
Engine has moved without a hiccup (ok minor one cos controller speeds
Does this help ?
Plus if you wanted more controllers but still 2 loops then replace DPDT
switches with rotary switch. Still each track has one connection but
controllers connected to all switches.
http://www.aglasshalffull.org/article-multi-throttle.html explains the
difference between section control (passing trains between different
controllers) and cab control (switching the complete route for a train
to a single controller).
On Sun, 6 Jun 2010 08:40:13 -0700 (PDT), " firstname.lastname@example.org"
Thanks to all the info...I'm not electrically minded much. I've
managed to get round this by simply having a switch in my controller
lead which stops any current from going back into it from another
controller. I know it sounds primative but it does what I need it
The Zero ST
The only problem there is that you need to remember to throw the
A very basic safety addition is to solder a motor vehicle tail lamp
bulb in series (ie in one lead). About 25 watts is right.
With a train running the bulb will only just glow and you'll lose
about half a volt.
If you forget the switch then the bulb will glow brightly to remind
you without any damage to anything.
Why would it burn out???
I first tried the technique back in the early 1970s when I started to
build transistor controllers. I've never had a bulb burn out, even
after 20 odd years of use. They only get a tiny voltage heating them.
Mine were old dual filiment bulbs with one filiment gone - useless
on motorcycles :-)
You could get two controllers on full speed and opposite polarities
connected across the bulb - that would blow the 12 volt bulb, but it
would burn both controllers out without the bulb.
If you're using early H&M point motors you might vibrate the bulb
filament until it broke, but your trains would keep falling off the
track so you'd know! ;-)
On 22/06/2010 04:04, email@example.com wrote:
Quite so. A single controller should not deliver more than about one
ampere for OO use. A 25 watt car lamp will rate at 2 amps, but will
handle about twice that before it burns out.
BTW, some older controllers will deliver too much power, which IMO is
the other reason they should not be used. Main reason: non-standard
grounding/isolation from earth.
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