6
6.2
Positioning mode (P0700 = 3, from SW 2.1)
6-358
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SIMODRIVE 611 universal Description of Functions (FBU) – 04.05 Edition
Table 6-10
Restrictions for axis/encoder, continued
Axis/encoder
Restrictions
t
VDC
link
P1162 (B)
Saving both drives A and B
Saving the encoder values for a double–axis module (drive A/B).
P1162 (A)
Rotary
axis
en-
dlessly
rotating
(modulo
rotary
axis)
Absolute value
encoders
The gear ratio can be freely selected (fault 139 is no longer output).
Example:
P0237:0 = 3
P0238:0 = 1
After the measuring system has been adjusted, the position of the load is
determined from the absolute position of the motor measuring system via
the gearbox factor (Ü=P0238:8/P0237:8). In order to determine the clear
position of the load, then it must be guaranteed that after being powered–
down, the motor can only move within half of the absolute encoder range
that can be represented (coast down or manual motion). This is the rea-
son that it is not permissible to use single–turn absolute value encoders.
Exceptions are possible if the user can ensure that the drive does not
move by more than half of an encoder revolution.
Important:
If half of the absolute encoder range that can be represented is exceeded
after powering–down, then the assumed actual position is incorrect and
after powering–up again no fault or warning is generated!
Note:
When the DC link voltage starts to ramp–up, the DC link coupling
must be maintained in order to supply the electronics.
If a fault condition develops, fault 149 (incorrect data for modulo drive
with absolute value encoder and any gearbox factor). In this case,
P1162 (minimum DC link voltage) should be checked as the encoder
data is saved when the entered threshold value is fallen below. The
axis must be re–adjusted after fault 149 occurs.
If the position setpoint (reference value inversion is selected when
commissioning the drive, then initially, a power–on must be carried–
out. The reference point can only be set after this.
Notice:
If the drive goes into regnerative operation after power–down, then this
can also cause problems when saving data if the control board is re–acti-
vated by the energy fed back.
From SW 8.2:
As long as the signals were still not available at terminals 48 and 63 of
the NE module, the electronics power supply of the control board can be
shut down again after run–up.
6 Description of the Functions
01.99
! not 611ue !
04.05