User Manual 08/2003 Edition

5
5 Description of the Functions 02.99
5.5 SIMODRIVE POSMO A functions
Reference
approach to a
BERO proximity
switch with
direction reversal
5-148
The reference point approach is executed via program. The axis traverses
with direction reversal depending on the reference cam signal.
Zero marks
Reference cam
signal
(e.g. from BERO)
Traversing profile
ÄÄÄÄÄ
Reference mark
Fig. 5-6 Reference approach to the BERO with direction reversal
Prerequisites:
Connect the reference cam signal to terminal 1
(X5, I/Q1, refer to Chapter 2.3)
Reference cams
Define terminal 1 as input and directly transfer the input terminal
signal into the start byte
(e.g. start byte bit 7 ––> P31 = 25, refer to Chapter 5.5.10)
Program the following traversing program (example):
Program block (e.g. block 13)
– SMStart bit 7 as start condition
– Program control word (PSW) = 224dec (00 1110 0000bin) (E0hex)
(closed–loop speed controlled, with approximate positioning, with
negated start byte, skip if the start byte is not fulfilled)
– Speed e.g. 20 % (= approach velocity)
– Acceleration 100 %
Program block (e.g. block 14)
– SMStart bit 7 as start condition
– Program control word (PSW)
= 384dec (01 1000 0000bin) (180hex)
(closed–loop speed controlled without negated start byte)
– Speed e.g. –5 %
(= shutdown velocity with direction reversal)
– Acceleration 100 %
– Program end when the end of the block is reached
Start program
As soon as ZSW.14 = ”0” (outside traversing block) is signaled, the
reference point can be set with STW.11 (start referencing / stop referencing).
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SIMODRIVE POSMO A User Manual (POS1) – 08.03 Edition