Magnum 20SRM Features
Connections:
On the rear of the Magnum 20
-
SRM there is a pair of connectors labelled ‘TO TRACK’ which you use to
connect the Magnum SR to your track. If your train is on the track facing forward, and you connect the
red terminal to the right rail, and the black terminal to the left rail, the train will go forward when the
forward/reverse switch is in the forward position. If the engine moves backwards, swap the track wires.
The best way to connect the Magnum 20 SRM to the track is with the included banana plug. You can
attach your wire to the banana plug, and then just plug it into the back of the unit.
In addition to the TRACK connection, there is a connection which provides full voltage (24
-
32VDC) output
which can be used to power accessories such as lighting or switch motors. You can connect to these
terminals with a banana plug (additional plugs are available from Bridgewerks) , or by unscrewing the
connection a little, and then tightening down on the bare wire.
The yellow connectors are for use by the RC
-
100 remote control (not included).
Speed Governor:
Bridgewerks’ exclusive “speed
-
stop” can be used as a safety device to limit the maximum speed of your
trains. The speed stop consists of a metal plate which is held in place with a thumb screw. To adjust the
speed stop, loosen the thumb screw, adjust the throttle slide control so that the train is going as fast as
you want to allow, and then slide the speed stop down to limit the maximum speed. Tighten the thumb
screw. Now you can move the throttle control from 0 up to the maximum selected speed.
Momentum:
The 20
-
SRM features a momentum control which will limit the acceleration and deceleration of the
trains. When momentum is enabled, and you move the throttle from the minimum to the maximum, the
train will slowly accelerate from a stop to the maximum speed. Similarly if the throttle is moved quickly
from maximum to 0, the train will slowly decelerate to a stop. Momentum adds another dimension of
realism to your model railroad. In addition, the combination of speed governor and momentum makes it
easier to limit derailments when younger engineers are at the controls.
Direction Control:
The Magnum 20 SRM has a direction control switch which will change the direction of the locomotive. If
the locomotive runs backwards when the switch is in the forward position, reverse the connections going
to the track. Turning the switch to Reverse will also reverse the direction of the train.
Overload Protection:
In the event of an overload, the Magnum 20
-
SRS has two different ways of protecting itself and your
train from damage: A manual circuit breaker on the left side of the rear panel. The button will pop out
and the power to the track will be cut off. If this happens, correct whatever caused the overload, wait 2
or 3 minutes and then push the switch to reset it.
In addition, there is an automatic thermal cutoff inside the controller, which will be activated in the event
of an overload. This will reset itself automatically in 2
-
3 minutes after the cause of the overload is re-
moved.
Optional Remote Throttle Capability (RC
-
100):
On the back of the Magnum SR there is a pair of yellow terminals for the remote control—plug the
receiver into these two yellow terminals (it will automatically also plug into the accessory power pins),
and provide you with wireless remote control over the throttle. There is also an accessory special
button available from Bridgewerks when one of these buttons is plugged into the yellow terminals, the
train will not move unless the button is being held in. This is a nice way to give children access to con-
trolling the train with the speed parameters still under control.
Wire:
Use heavy gauge wire to connect your power controller to the track. For distances of up to 15 feet,
you should use 12 gauge wire. For distances over 15 ft, you use 10 gauge wire. Although the track
itself is similar to a very heavy gauge wire, in larger layouts, significant loss can occur from the
connections between sections of track. To improve this, run multiple power connections to the
track from the controller and/or use track clamps rather than slider type couplers. In outdoor
layouts which are exposed to extreme temperatures, the track will expand and contract as the
temperature changes, and slider type couplers may have to be used.
Outdoor operation
Garden railways are often installed outdoors and Bridgewerks controllers are built to be used with
outdoor railroad layouts. However, they are not waterproof, and as with any electronic equipment,
they should not be left outdoors when not in use.
To make this easy, the connections are all made so
that they can simply be unplugged and the controller can be carried indoors.
Accessory Power
On the back of the Magum 20SRM in addi-
tion to the pair of yellow remote terminals,
and the terminals that provide power to the
track, there is a pair of terminals for accesso-
ry power. This pair of terminals provides an
unregulated DC power source that will be
from 18 to 30 V depending on how much
power you are drawing from the connection.
This pair of terminals can be used to power
an accessory such as the MAG
-
MATE or UR
-
15 which give control over an additional track, which allows the ample power of the 20
-
SRM to be
shared with other tracks as your layout expands.
