www.baldormotion.com
Input / Output 4-15
MN1928
4.5.2 Encoder inputs
The encoder inputs are available on pins a7-a10, b7-b10 and c7-c10. See section 4.2.1.
Two incremental encoders may be connected to NextMove ES, each with complementary A, B
and Z channel inputs. Each input channel uses a MAX3095 differential line receiver with pull
up resistors and terminators. Encoders must provide RS422 differential signals. The use of
individually shielded twisted pair cable is recommended. See section 8.1.10 for details of the
encoder power supply.
CHA-
CHA+
to CPU
Vcc
NextMove ES
MAX3095
120R
10k
b7
b10
Shield
a32
Connect overall shield to
connector backshells /
shield connections.
Twisted pair
MicroFlex
FlexDrive
II
Flex+Drive
II
MintDrive
II
encoder output
a11
DGND
Connect internal shield to DGND.
Do not connect other end.
CHA-
CHA+
1
6
‘X7’
CHB-
CHB+
MAX3095
120R
a7
c10
Twisted pair
CHB-
CHB+
2
7
CHZ-
CHZ+
MAX3095
120R
b8
b9
Twisted pair
CHZ-
CHZ+
3
8
to CPU
to CPU
Vcc
10k
Vcc
10k
Figure 14 - Encoder input 0 - typical connection from a drive amplifier
(e.g. Baldor MicroFlex, FlexDrive
II
, Flex+Drive
II
or MintDrive
II
)
4.5.2.1 Encoder input frequency
The maximum encoder input frequency is affected by the length of the encoder cables.
The theoretical maximum frequency is 20 million quadrature counts per second. This is
equivalent to a maximum frequency for the A and B signals of 5 MHz. However, the effect of
cable length is shown in Table 3:
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