Non-Sound Decoder MX600 - MX638 and Sound Decoder MX640 - MX659 Page 21
CV
Denomination
Range
Default Description
#4
Deceleration rate
0 - 255
(1)
The value multiplied by 0.9 equals’ deceleration time in
seconds from full speed to a complete stop.
The effective default value for sound decoders is usual-
ly not the value given here, but is determined by the
loaded sound project.
#23
Acceleration trimming
0 - 255
0
To temporarily adapt the acceleration rate to a new load
or when used in a consist.
Bit 0 - 6: entered value increases or decreases
acceleration time in CV #3.
Bit 7 = 0: adds above value to CV #3.
= 1: subtracts above value from CV #3.
#24
Deceleration trimming
0 - 255
0
To temporarily adapt the deceleration rate to a new
load or when used in a consist.
Bit 0 - 6: entered value increases or decreases
deceleration time in CV #4.
Bit 7 = 0: adds above value to CV #4.
= 1: subtracts above value from CV #4.
#121
Exponential
acceleration
0 - 99
0
Acceleration time (momentum) can be stretched in the
lower speed range:
Tens digit: Percentage of speed range to be
included (0 to 90%).
Ones digit: Exponential curve (0 to 9).
EXAMPLE:
CV #121 = 11, 23 or 25 are typical initial test values.
#122
Exponential
deceleration
0 - 99
0
Deceleration time (momentum) can be stretched in the
lower speed range:
Tens digit: Percentage of speed range to be
included (0 to 90%).
Ones digit: Exponential curve (0 to 9).
EXAMPLE:
CV #122 = 11, 23 or 25 are typical initial test values.
#123
Adaptive
acceleration and
deceleration
0 - 99
0
Raising or lowering the speed to the next internal step
occurs only if the preceding step is nearly reached. The
tolerance for reaching the preceding step can be de-
fined by this CV (the smaller this value the smoother
the acceleration/deceleration).
Value 0 = no adaptive accel. or decel.
Tens digit: 0 - 9 for acceleration (1 = strong effect)
Ones digit: 0 - 9 for deceleration
EXAMPLE:
CV #123 = 11: strongest effect; sometimes affects
the start up too much.
CV #123 = 22: typical setting.
#394
Bit 4: Faster accelera-
tion
From SW-Version 33.25
0
– 255
-
Bit 0 = 1:: Light flashes at switchgear sound..
Bit 4 = 1: Accelerates faster and sets sound to high
load when regulator is moved quickly to full speed
Bit 5 = 1: Blending of chuff samples
CV
Denomination
Range
Default Description
#309
Brake key
From SW-Version 33.25
0 - 29
0
The key defined here acts as a brake key according to
the rate defined in CV #349 (the normal
– higher – de-
celeration time in CV #4 is thereby ignored).
#349
Brake time
From SW-Version 33.25
0 - 255
0
To achieve the desired effect, the deceleration time in
CV #4 must be set to a very high value (@ 50 … 250)
but the brake time in CV #349 rather low (5 … 20). This
simulates a coast
ing effect with the “regulator at 0”,
while the brake key results in a short stopping distance.
#146
Compensation for gear
backlash
during direction changes
in order to
reduce start-up jolt.
NOT for MX621
0 - 255
0
= 0: no effect
= 1 to 255: the motor spins at minimum rpm (according
to CV #2) for a specific time and only starts to acceler-
ate after this time has elapsed. This CV will only be ex-
ecuted after a direction change.
How much time is required to overcome the backlash
depends on various circumstances and can only be de-
termined by trial and error.
Typical values are:
= 100: the motor turns about 1 revolution or a
maximum of 1 second at the minimum speed.
= 50: about ½ a turn or max. ½ second.
= 200: about 2 turns or max. 2 seconds.
Important: The minimum speed must be set correctly,
so that the motor actually turns at the speed step de-
fined as the lowest step in CV #2. Also, CV #146 is only
useful if the load regulation is set to maximum or at
least close to it (i.e. CV #58 = 200
– 255).
NOTE: The actual acceleration and deceleration rates for HLU brake sections (ZIMO signal controlled
speed influence) are determined by CV #49 and #50.
Momentum
– explained in more detail:
The momentum (acceleration and deceleration rates) according to CV #3 and #4 refers to the 255 internal steps which
are spaced equally from 0 to full speed. The selected speed table, whether 3-step or 28-step, does not influence the
momentum behavior.
The momentum CANNOT be embettered by bending the speed curve in the speed tables, but is very much possible
with the “exponential acceleration/deceleration” in CV #121 and #122.
