Questions, Answers & Tips - 2
Using such center-off/momentary toggles has the benefit of only
powering any given Tortoise when it's in motion. The power sup-
ply is not being loaded down by Tortoises at stall. I see a poten-
tial issue if two or more operators try to throw the same turnout
at the same time (and thus are holding down their respective
momentary toggles). This could present a short circuit condition,
with possible bad results.”
He suggests a stall-motor 555-based circuit a la the Rob Paisley
"Electronics for Model RRs" website:
Multiple press-button (or momentary center-off toggle) switches
can be parallel-connected, and are only switching 12-volt low-
current logic lines. The 555 chip does not care if multiple opera-
tors try to throw the turnout at the same time, and will work out
what to do if near-simultaneous contradictory commands are
received. As always with model railroading, there are umpteen
different ways to peel a feline.
“In Free-mo we use Mike's diagram,” says Chris Palomarez. “It's
the simplest – two components (two double-pole, double throw
switches) – and is very easy
to wire. It's been 100% reli-
able and not subject to
bad momentary buttons/
bad electronic boards. We
use DPDT on/on push but-
tons (2) due to liking their
neutrality. They are not subject to having a toggle lever not in
alignment with the points of the turnout.
“We use these switches:
“Many installations are 12 years old. The switches are very reli-
able with normal usage. There is a tactile click to them when
being pushed that helps the operator know by feel when contact
has been made and switch has been flipped. I have only replaced
3 in the past 12 years,” Chris said. “These were damaged from
the back of the switch when a module leg broke them, not from
normal usage.”
Toggles tend to break from usage. Some less-acclimated opera-
tors will try to throw the toggle the wrong way, side to side
versus up and down, instantly disabling the toggle switch.
With these push buttons, the layout becomes very intuitive for
2
2: Push buttons don't
show any switch posi-
tion but can be more
durable than toggles.
3: The LK&O Railroad uses a latching relay and momen-
tary pushbuttons to control Tortoise machines.
MRH-Feb 2014
