ZIMO MX695, Инструкция по эксплуатации

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Page 22 Large-scale Decoder & Sound Decoder MX695/6/7/9

The default value “0” in CV #57 selects the “relative reference”, which automatically adjusts the
reference voltage to the available track voltage. This setting is only useful though if the system
can keep the track voltage constant at all times (stabilized track output) and the resistance along
the track kept to a minimum. All ZIMO systems keep the track voltage stable even older systems,
but not every system from other manufacturers do, especially the relatively cheap systems built
before 2005. It is not recommended to set
CV #57 to “0” with systems that don’t keep track volt-
age stabilized. Instead set this CV about 2V below track voltage (i.e. 140 for 16V).

CV #57 can also be used as an alternative to CV #5 (top speed), which has the advantage that
the full resolution of the 255 speed steps remains available.
CV Designation Range Default Description
#57 Voltage Reference 0 - 255 0
Absolute voltage in tenth of a volt applied to the mo-
tor at full speed (max. throttle setting).
Example: A system without stabilized track voltage is
set to 22V at idle but drops to 16V under load: A
good setting would be CV #57 = 140…150.
CV #57 = 0: automatically adjusts to the track volt-
age; only useful with stabilized track voltage.
Tweaking the motor regulation
The motor’s performance, especially at crawling speeds (should be a smooth as possible), can
be fine-
tuned with the following CV’s:
CV #9
– Motor control frequency and EMF sampling rate
The motor is controlled by pulse with modulation that can take place at either low or high fre-
quency.
Low frequency (30
– 159Hz) is only useful for very few locomotives with very old motors (i.e.
AC motors with field coils instead of permanent magnets).
High frequency ( 20 kHz by default, up to 40 kHz as per CV #112) on the other hand is quiet
and easy on the motor.
Power to the motor is interrupted periodically (50
– 200 times/sec.), even when operating at
high frequency, in order to determine the current speed by measuring back-EMF (voltage gen-
erated by the motor). The more frequent this interruption takes place (sampling rate), the better
the load compensation performs; but that also causes power loss and increased noise. By de-
fault, the sampling frequency varies automatically between 200Hz at low speed and 50 Hz at
maximum speed.
CV #9 allows the adjustment of the sampling frequency as well as the sampling time. The de-
fault value of 55 represents a medium setting.
CV # 56
– The PID regulation
The motor regulation can be tailored to motor type, vehicle weight and so on, by using different
P
roportional-
I
ntegral-
D
ifferential values. In reality however, changing the differential value can
be omitted.
CV #56 allows the proportional value (tens digit) as well as the integral value (ones digit) to be
set individually. The default value of 55 represents a medium setting, at which a certain auto-
mated fine-tuning is performed by the decoder software.
CV Designation Range Default Description
#9
Motor control
frequency
and
EMF sampling rate
(Algorithm)
55
high fre-
quency,
medium
scanning
rate
algorithm
01 - 99
high fre-
quency
with
modified
EMF
scanning
rate
algorithm
255-176
low fre-
quency
55
high fre-
quency,
medium
scanning
rate
algorithm
= 55: Default motor control with high frequency
(20/40kHz), medium EMF sampling rate that automat-
ically adjusts between 200Hz (low speed) and 50Hz
and medium EMF sampling time.
<> 55: Modification of automatic adjustments with:
tens digit for sampling rate and
ones digit for sampling time.
Tens digit 1 - 4: Lower sampling rate than default
(less noise!)
Tens digit 6 - 9: Higher sampling rate than default
(to combat jerky movements!)
Ones digit 1
– 4: Shorter EMF sampling time (good
for coreless motors, less noise, more power)
Ones digit 5 - 9: Longer EMF sampling time (may be
needed for 3-pole motors or similar).
Typical test values against jerky driving:
CV #9 = 55 (default)

83, 85, 87, ...
CV #9 = 55 (default)
 44, 33, 22, …
= 255 - 178: Low frequency (for old motors only!)
–
PWM according to formula (131+ mantissa*4) *2exp. Bit 0-4 is
“mantissa”; Bit 5-7 is “exp”. Motor frequency is the reciprocal of
the PWM.
Examples:
#9 = 255: frequency at 30 Hz,
#9 = 208: frequency at 80 Hz,
#9 = 192: frequency at 120 Hz.
#112
Special ZIMO
Configuration bits
0 - 255
4 =
00000100
Bit 5 = 0
(20 kHz)
Bit 1 = 0: Normal acknowledgement.
= 1: High frequency acknowledgement
Bit 2 = 0: Loco number recognition OFF
= 1: ZIMO loco number recognition ON
Bit 3 = 0:
12-Function Mode
= 1: 8-Function Mode
Bit 4 = 0: Pulse chain recognition OFF
= 1: Pulse chain recognition (for old LGB)
Bit 5 = 0: 20 kHz motor control frequency
= 1: 40 kHz motor control frequency
Bit 6 = 0: normal (also see CV #29)
= 1: „Märklin brake mode
#56
P- and I- Value
for
BEMF motor regulation
55
medium
PID
setting
01 - 199
modified
settings
55
= 55: Default setting using medium PID parameters.
= 0 -
99: Modified settings for “normal” DC motors
(Bühler etc.).
= 100 - 199: Modified settings for coreless motors
(Faulhaber, Maxon etc.)
Tens digit 1 - 4: Lower proportional value than default
Tens digit 6 - 9: Higher proportional value than default
Ones digit 1 - 4: Lower integral than default
Ones digit 6 - 9: Higher integral than default
Typical test values against jerky driving:
CV #56 = 55 (default)

33, 77, 73, 71...