method makes it possible to place the point of discontinuity at any point
within the encoder’s entire measuring range. By default,
MTBase
will be set
to the lowest possible value for the parameter, i.e. reliably outside of the
encoder’s value range: In this case, the full bipolar range will remain
unaffected, as values will never fall below this
MTBase
threshold (see
Section "Channel 1: Interface X7" on page 59).
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P 548[0] - ENC_CH1_MTEnable
= MultiTurn as SingleTurn
The
MTEnable
parameter makes it possible to use multi-turn encoders as
single-turn encoders for test purposes. Negative logic: Default MTEnable = 0
means "MultiTurn-Enable ON".
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P 549[0] - ENC_CH1_Corr
= Signal correction type
The GPOC routine used for track signal correction purposes for sine/cosine
signals is used to compensate for systematic errors. The routine is controlled
with the Corr and CorrVal parameters (see Section "Signal correction GPOC
(Gain Phase Offset Correction)" on page 74).
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P 551[0] - ENC_CH1_EncObsMin
= Encoder monitoring minimum, sqrt
(a^2+b^2)
The parameter
EncObsMin
is used to scale the Sin/Cos wire break
monitoring and represents the “downwards threshold” for an error message.
The default setting is 0.2, corresponding to approx. 20% of the track signals’
amplitude (approx. 80% corresponds to approx. 1 Vss). If EncObsMin is set to
0, Sin/Cos wire break monitoring will be disabled (also see Section "Channel
1: Interface X7" on page 59).
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P 552[0] - ENC_CH1_AbsEncStatus
= Error and status codes (absolute
encoder)
The AbsEncStatus parameter is used to display status information for
HIPERFACE encoders. In subindex [0], the read “TypeKey” for the
HIPERFACE encoder will be indicated (one byte), for example.
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P 553[0] - ENC_CH1_PeriodLen
= Sin/Cos linear encoder and
P 554[0] - ENC_CH1_DigitalResolution
- linear absolute encoder
are the length of an analog Sin/Cos signal period in nanometres and the
length of a digital increment of the position from the absolute value interface
in nanometres. Both parameters are used for linear EnDat encoders and
linear HIPERFACE encoders (instead of MultiT and SingleT bits (rotary)). In
MOOG
ID No.: CB40859-001 Date: 11/2020
MSD Servo Drive - Device Help
66
6 Encoder
contrast, linear SSI encoders are treated as rotary SSI encoders (in this case,
it is impossible to determine that the system is a linear encoder system based
on the encoder head). Likewise, linear Sin/Cos encoders without an absolute
value interface are treated as “rotary” encoders (if run as commutation
encoders, the number of tracks, or lines (
Lines
) and the encoder gearing
(
Num, Denom
) must be used to establish the relationship to the linear
motor’s magn. pole pair subdivision). Only in the case of Sin/Cos encoders
with distance-coded reference marks will the system determine, based on
PeriodLen
> 0, that the encoder system is linear and not rotary.
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P 555[0] - ENC_CH1_Info
= Encoder Information
This parameter is available to the user so that they can enter a text of their
choice (maximum of 31 characters). This text should be used to describe the
encoder on channel Ch1
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P 616[0] - ENC_CH1_CycleCount
= Sampling cycle in: n x 125 µs
(microseconds)
The CycleCount parameter can be used to slow down the timing for the
cyclical SSI encoder evaluation. By default, CycleCount = 1, i.e. the default
setting corresponds to 125 µs sampling and cycles for the encoder
evaluation. Different settings must be viewed as special cases and
accordingly must only be used when necessary. (see Section "SSI
(cyclical) X7" on page 69).
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P 610[0] - ENC_CH1_NominalIncrementA
= distance coded absolute
encoder
P 611[0] - ENC_CH1_NominalIncrementB
= distance coded absolute
encoder
The
NominalIncrementA
and
NominalIncrementB
parameters make it
possible to run Sin/Cos incremental encoders (without an absolute value
interface) with analog distance-coded reference marks. For example, if you
were using the Heidenhain ROD280C with 18000 Sin/Cos tracks per
revolution and 36 distance-coded reference marks, you would need to set
NominalIncrementA to 1000 signal periods and NominalIncrementB to 1001
signal periods. This functionality is enabled if
NominalIncrementA
> 0. (see
Section "Increment-coded reference marks" on page 105).
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P 617[0] - ENC_CH1_AbsInitMode
= Mode absolute value formation
AbsInitMode
can be used to select various possible settings for the absolute
