Application Examples For Sg; Examples For Safe Input Of Ratios - Siemens SINUMERIK 840D Description Of Functions

11.03
Defining machine data Table 3-28
Table 3-29
Table 3-30
3.5.8

Application examples for SG

Please refer to Chapter 7, "Configuring example" for an example of safely-
reduced speed.
3.5.9

Examples for safe input of ratios

Task assignment The gear ratio (encoder/load) must be safely sensed on a spindle with a four-
stage gearbox.
Two examples are given, one with a
2-encoder system (ex. 1, refer to Fig. 3-13 Spindle with a 2-encoder system)
and one with a
1-encoder system (ex. 2, refer to Fig 3-14 Spindle with a 1-encoder system).
Example 1: Spindle with a 2-encoder system
The two channels are monitored by comparing the speed sensed by the second
encoder with the speed of the motor encoder, taking the gear ratio into account.
The ratio selection does not have to be safely monitored and only has to
involve one channel.
•
Assumptions for
example 1
© Siemens AG 2003 All Rights Reserved
SINUMERIK 840D/SIMODRIVE 611 digital SINUMERIK Safety Integrated (FBSI) - Edition 11.03
Supplying MDs for SGEs
For 840D
Limit value MD number
SG1
36931[0]
SG2
36931[1]
SG3
36931[2]
SG4
36931[3]
Supplying MDs for SGEs
Signal Assignment
SGE MD number
SG select, bit 1
36972[1]
SG select, bit 0
36972[0]
SG override selection bit 3
36978[3]
SG override selection bit 2
36978[2]
SG override selection bit 1
36978[1]
SG override selection bit 0
36978[0]
Supplying MDs for override values
Override For 840D
MD number
0
36932[0]
1
36932[1]
2
36932[2]
3
36932[3]
The gear stage is selected from an NC program with an H function via the
PLC user program.
3 Safety-Related Functions
3.5 Safely-reduced speed (SG)
For 611 digital
Value MD number
1000
1331[0]
2000
1331[1]
4000
1331[2]
5000
1331[3]
Value Remarks
01 06 04 02
01 06 04 01
00 00 00 00 Not configured
00 00 00 00 Not configured
01 06 04 04
01 06 04 03
For 611 digital
Value MD number
100
1332[0]
80
1332[1]
50
1332[2]
30
1332[3]
Value
1000
2000
4000
5000
Value
100
80
50
30
3-103