HOW DO I USED THE DIFFERENT BRAKING SYSTEMS?
Like a real train, TM4 offers three different braking systems, dynamic
brakes, independent (locomotive) brakes and automatic (train) brakes.
Dynamic Brakes use the locomotives traction motors as generators
which drive a bank of resistors that turns the energy into heat.
Independent Brakes use air pressure to control brakes that operate
only on the locomotive itself.
Automatic Brakes use air pressure to control brakes that operate on
the entire train, including the locomotive.
Dynamic brakes are useful for limiting the train's speed over long periods
of time, such as descending a grade. They work best at medium speeds; for
example, the manual for the EMD SD-40 locomotive states that maximum braking
strength is obtained between 18 and 25 mph. At low speeds the dynamic brakes
become ineffective since the braking action is dependent on the wheels
turning the traction motors.
To use the dynamic brakes first gradually lower the throttle to idle. Then
you must pause before proceeding (the SD-40 manuals specifies a 10 second
wait). You can then push the button to enable dynamic brakes and use the
throttle to control the amount of braking desired.
Automatic brakes are used to slow and stop the entire train. They work by
controlling air pressure in lines that go from the locomotive along the
entire train. Normally when travelling you would have the brake lever in the
left position (release). When brakes are needed move the lever to the right
to the service position. This releases air from the equilizing reservoir in
the engine which in turn releases air from the brake pipe travelling the
length of train. Releasing pressure in the brake pipe causes pressure to
increase in the brake cylinder thus applying the brakes to the wheels. You
can control how much braking you get by moving the lever from the service
one position left to the lap position. This position holds the braking level
at the amount set while the lever was in the service position. If you need
more braking move the lever back to the service position to increase the
brake cylinder pressure to the desired level.
The automatic brakes also have an emergency position which causes the
pressure in the brake lines to be released instantly causing maximum braking
action as quickly as possible.
The automatic brakes can be used at the same time as the dynamic brakes
if necessary.
Independent brakes work in a similar manner to the automatic brakes except
they only set the brakes on the locomotive. The independent brake control
works differently too, in that you don't need to switch from service to lap
to set the desired amount of braking you just move it a step at a time to
the right until the desired amount of braking is obtained and move it all
the way to the left to release ("bail off") the brakes.
THE SPEED LIMIT KEEPS CHANGING UNEXPECTEDLY AND STOPS MY RUN. I'M TRYING TO
FOLLOW THE SPEED LIMITS IN THE MANUAL BUT IT'S NOT WORKING. HOW EXACTLY DO
THE SPEED LIMITS WORK?
The problem is that the speed limits listed in the TM4 manual and the actual
limits coded in the routes do not match. To add further to the confusion,
most of the routes described in the manual are longer than what is actually
included in the routes you can drive so you also have to figure out what part
of the chart actually applies.
The manual also says that you will receive warnings of speed limit changes
on the status line in the middle of the screen. Unfortunately, this is not
always true...some routes have it and some don't. You cannot rely on this
warnings.
One solution is an independently developed route chart that matchs the
actual encoded speed limits. You can download this from the TM4 Forum
here at Train-Sim.Com
One other solution is to turn off speed limit enforcement in the TM4 setup
menu.
HOW CAN I LEARN WHAT THE SIGNALS MEAN?
TM4 uses realistic signals, but there are quite a large number of them for
the new engineer to learn. They are all shown in the TM4 book, but over
several pages so they are not convenient to reference.
The answer is available in a single page signal reference which you can
download here.
Download the signal reference.
ALONG THE SIDE OF TRACKS I SEE SIGNS WITH JUST A "W" ON THEM. WHAT DO THEY
MEAN?
The "W" stands for "whistle". Generally, there is a road just up ahead and
you need to sound a warning with your horn.
WHAT IS THE PROPER WAY TO GET A TRAIN STARTED FROM A DEAD STOP?
There is some technique in getting a train to initially move, especially
if dealing with a long freight.
First, you must have the brakes fully released. In a real train this can
take as long as 10 minutes! Watch the pressure gauges and wait until the
brake cylinder gauge is at zero.
With the brakes off move the throttle control to notch 1. A heavy train
will not yet start to move so every few seconds advanced by another notch
until movement begins. Though TM4 does not simulate it, in a real train
care has to be taken to not accelerate too fast until the train is
stretched (all the slack has been removed in the couplers and draft gear).
So, for greatest realism back off a notch or more if acceleration is too
rapid. Once the train is stretched advance the throttle as desired.
This information is based on the Electro-Motive Division SD40-SDP40
Operator's Manual.
ONCE MOVING, HOW DO I ACCELERATE THE TRAIN?
There is some technique involved in accelerating properly. In general, you
can advance the throttle as rapidly as desired. However, using the loading
meter (the large meter indicating amps) is the best guide. Each time you
advance the throttle the amps reading will go up but after a moment will
go back down somewhat. At this point the motors are ready to absorb more
power and you can advance the throttle another notch. This technique gives
you maximum acceleration without slipping.
This information is based on the Electro-Motive Division SD40-SDP40
Operator's Manual.
Copyright © 2001 by Nels Anderson. All Rights Reserved.