Lika EM58 MB, User Manual

Page: 69 / 92

ES58 • EM58 MODBUS®
The Custom total resolution [0002-0003 hex] would be lower than the
Custom counts per revolution [0000-0001 hex]
, however the above setting
is accepted.
WARNING
If you have set the preset, when you change the value next to the
Custom total
resolution [0002-0003 hex]
parameter, then you must check the value in the
Preset value [0004-0005 hex] parameter and perform the homing operation
(bit 11
Perform counting preset
in
Control Word [0009 hex]
= 1).
EXAMPLE
Multiturn encoder EM58
12/16384MB-...
.
The physical resolution is as follows:

Hardware counts per revolution
= 4,096 cpr (2
12
)

Number of hardware revolutions
= 16,384 turns (2 14 )

Overall hardware resolution
= 67,108,864 P (2
26
)
You need to set a single-turn resolution of
2,048 counts per revolution
while
1,024 revolutions
are required:
•
Enable the
Scaling function
:
Operating parameters [0008 hex]
, bit 0
= 1
•
Set the number of distinguishable steps per revolution:
Custom counts
per revolution [0000-0001 hex]
= 2,048 (0000 0800 hex)
•
Set the overall resolution:
Custom total resolution [0002-0003 hex]
= 2,048

1,024 = 2,097,152 (0020 0000 hex)
•
Save the set parameters (
Save parameters
in the
Control Word [0009
hex] register; see on page 74)
WARNING
We suggest setting values which are a power of 2 (2 n : 2, 4, …, 2048, 4096, 8192,
…) to be set in the
Custom counts per revolution [0000-0001 hex]
and
Custom total resolution [0002-0003 hex]
registers to avoid counting errors.
If
Custom counts per revolution [0000-0001 hex]
and/or
Custom total
resolution [0002-0003 hex]
values change, the
Preset value [0004-0005
hex]
must be updated in accordance with the new resolution. A new preset
operation is also required.
MAN ESx58x_EMx58x MB E 1.3 Programming parameters 69 of 92