Siemens SINUMERIK 840C - Manual (Page 259)

6 NC Machine Data (NC MD), NC Setting Data (NC SD) 09.95
6.5 Spindle-specific MD (spindle data)
• Encoder mounted to the spindle via the measuring gear; SIPOS unconditioned signal
encoder and HMS servo loop module
b
= 0.5 • 10 -3 degrees
p = 2500 pulses per revolution
f = 8 HMS pulse multiplication
r1 = 2 2 spindle revolutions correspond to
r2 = 3 3 encoder revolutions
If these factors are introduced into the formula then:
MD 4550 = 240 000
MD 4560 = 1 444 000
Reduction by the common factor 240 000 yields:
MD 4550 = 1
MD 4560 = 6
Example
Motor measuring systems as encoder with SIMODRIVE 611-D
G
= 0.5 • 10 -3 degrees
p = 2048 pulses per revolution
f = 128 pulse multiplication
r = 1
MD 4550 = 8192
MD 4560 = 5625
MD 458* = 128
f: Pulse multiplication for EXE/611D/HMS 458*
Default values Lower input limit Upper input limit Units
1 0
128
512 (as from SW 3)
–
Active on
Power On
The measuring system resolution can be adapted to any application using the HMS servo loop
module. The pulses arriving from the encoder are multiplied in two steps:
Pulse multiplication for HMS
Measuring system resolution
Measuring system
Pulse multiplication
hardware • 4
Pulse multiplication
by high-resolution
meas. syst. MD 458*
The following values are permissible for MD 458* when using a HMS servo loop module or
611D:
HMS: 1, 2, 4, 8, 16, 32, 64, 128
611D/PCU: 1, 2, 4, 8, 16, 32, 64, 128, 256, 512
Hence, the attainable maximum is a pulse multiplication by the factor 512.
6–74 © Siemens AG 1992 All Rights Reserved 6FC5197- AA50
SINUMERIK 840C (IA)