11.03
4 Data Descriptions
4.1 Machine data
© Siemens AG 2003 All Rights Reserved
SINUMERIK 840D/SIMODRIVE 611 digital SINUMERIK Safety Integrated (FBSI) - Edition 11.03
4-219
36918
MD number
$MA_SAFE_ENC_RESOL
Encoder pulses per revolution
840D
Default: 2 048
Min. input value: 1
Max. input value: 100 000
Change becomes effective after POWER ON:
Protection level (R/W) 7/2
Unit: -
Data type: DWORD
Applies from SW 3.4
Meaning
The number of pulses per revolution for a rotary encoder is specified here.
MD irrelevant for ....
a linear encoder
36920
MD number
$MA_SAFE_ENC_GEAR_PITCH
Spindle pitch
840D
Default: 10
Min. input value: 0.1
Max. input value: 10 000
Change becomes effective after POWER ON:
Protection level (R/W) 7/2
Unit: mm
Data type: DOUBLE
Applies from SW 3.4
Meaning
Gear ratio of gearbox between encoder and load for a linear axis with rotary encoder.
MD irrelevant for ....
a linear encoder
36921
MD number
$MA_SAFE_ENC_GEAR_DENOM[n]
Denominator of encoder/load gear
840D
Default: 1
Min. input value: 1
Max. input value: 2 147 000 000
Change becomes effective after POWER ON:
Protection level (R/W) 7/2
Unit: -
Data type: DWORD
Applies from SW 3.4
Meaning
Denominator of the gearbox between encoder and load, i.e. the denominator of the
fraction
No. of encoder revolutions /
No. of load revolutions
n = 0, 1, ... ,7 stands for gear stage 1, 2, ... 8
The current value is selected via safety-relevant input signals (SGEs).
Corresponds with …
MD 36922: $MA_SAFE_ENC_GEAR_NUMERA[n]
MD irrelevant for ....
a linear encoder
36922
MD number
$MA_SAFE_ENC_GEAR_NUMERA[n]
Numerator of encoder/load gear
840D
Default: 1
Min. input value: 1
Max. input value: 2 147 000 000
Change becomes effective after POWER ON:
Protection level (R/W) 7/2
Unit: -
Data type: DWORD
Applies from SW 3.4
Meaning
Numerator of the gearbox between encoder and load, i.e. the numerator of the fraction
No. of encoder revolutions
/ No. of load revolutions
n = 0, 1, ... 7 stands for gear stage 1, 2, ... 8
The current value is selected via safety-relevant input signals (SGEs).
Corresponds with …
MD 36921: $MA_SAFE_ENC_GEAR_DENOM[n]
MD irrelevant for ....
a linear encoder
36925
MD number
$MA_SAFE_ENC_POLARITY
Direction reversal actual value
840D
Default: 1
Min. input value: -1
Max. input value: 1
Change becomes effective after POWER ON:
Protection level (R/W) 7/2
Unit: -
Data type: DWORD
Applies from SW 3.4
Meaning
A direction reversal of the actual value can be selected using this data.
= -1:
Direction reversed
= 0 or = 1:
Direction not reversed
