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P 543[0] - ENC_CH1_MultiT
= Number of multi-turn bits: 0..14
Due to the design of the cyclical SSI interface as a motor feedback interface,
the number of multi-turn bits is limited to 14 (no limit to 14 bits in the case of a
SinCos interface with SSI one-time reading).
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P 545[0] - ENC_CH1_Code
= SSI decoding: BINARY(0) or GRAY(1)
Gray decoding will be selected by default. The other option is to use binary
decoding.
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P 546[0] - ENC_CH1_Mode
= Available SSI auxiliary settings
This parameter has a 16-bit hex value. With the default setting (0000h), SSI
wire break monitoring will be enabled. A value of 0001h will disable SSI wire
break monitoring, meaning that one bit less will be read.
Following is a list of what some of the terms in the table below stand for:
o
Data = Sequence of all data bits
o
EncObs = Wire break bit
o
Nothing = No bit
o
POdd = Odd parity bit
o
PEven = Even parity bit
o
Free = A free bit
ID
Value Name
546
ENC_CH1_Mode
0000h Data_EncObs
Default: with wire break
0001h Data_Nothing
0002h Data_POdd_EncObs
ODD Parity
0003h Data_Free_POdd_EncObs
0004h Data_POdd
0005h Data_Free_POdd
0006h Data_Free_EncObs
0007h Data_Free_Free_EncObs
000Ch Data_PEven_EncObs
EVEN Parity
Table 6.14: SSI mode parameters (all other values are reserved)
ID No.: 0842.26B.5-01 Date: 09.2020
ServoOne - Device Help
72
6 Encoder
ID
Value Name
000Dh Data_Free_PEven_EncObs
000Eh Data_PEven
000Fh Data_Free_PEven
001Fh Data_Free
Extra data reading
0020h Data_Free_Free
0021h Data_Free_Free_Free
0022h Data_Free_Free_Free_Free
Table 6.14: SSI mode parameters (all other values are reserved) (continue)
P 616[0] - ENC_CH1_CycleCount = Sampling cycle in: n x 125 µs (microseconds):
ENC_CH1_CycleCount can be used to slow down the timing for the cyclical SSI
encoder evaluation. By default, ENC_CH1_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 must only be used when necessary.
Monitoring the position difference
With SSI encoders, the position difference is monitored automatically. The limit value
is based on the maximum speed with reference to one scanning step (125µs). The
position difference between two scanning steps is restricted to this limit value. In the
event of an EMC disturbance, this limits the (incorrectly detected) tracking error and
the response of the controller.
6.5.7 Encoder gearing
NOTE
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Please read the general information on encoder gearing found in
Section "Introduction" on page 52 beforehand.
Encoder channels Ch1 to Ch3 each feature their own encoder gearing, while
encoder channel Ch4 (virtual encoders) does not feature
any encoder gearing.