Danaher Motion
05/2008
Wiring the Drive
S200-VTS Product Manual
55
6.7.6 Encoder
Outputs/Inputs
J4-19
CH A OUT/IN
J4-20
CH A OUT/IN
J4-21
CH B OUT/IN
J4-22
CH B OUT/IN
Outputs
Channels A and B are RS-485 compliant differential I/O that can be
configured as either inputs or outputs. Default is as outputs. When
configured as outputs and with high resolution feedback such as the SFD
device, Channels A and B provide position signals generated from the
feedback device that emulate a quadrature encoder.
The outputs are buffered by 5.0 V, 75LBC170 type RS-422 compatible line
drivers. Recommended load current is ±20 mA, which corresponds to a
line-to-line load resistance of 100
Ω
. These outputs can handle shorts to
I/O RTN indefinitely without damage.
The resolution of the Encoder Outputs (number of pulses per motor
revolution), is set by S1 (rotary switch), as follows:
S1
Position
Encoder Pulses/Revolution
0 User
settable
1
(factory default = 500)
1 512
2 1000
3 1024
4 2000
5 2048
6 4096
7 5000
8 8192
9 10000
1
User settable non-volatile PPR via the serial port.
Possible PPR are:
128, 512, 1024, 2048, 4096, 8192, 16384, 32768,
125, 500, 1000, 2000, 2500, 5000, 10000, 20000
The maximum output line frequency is 2.5 MHz. Limit line frequency to below
1.25 MHz, which corresponds to quadrature count frequency below 5 MHz, for
robust operation.
NOTE
The emulated encoder output is only available when using a high
resolution feedback device such as the SFD feedback to the base unit
or Encoder feedback to the option card. The emulated encoder outputs
have no signals when there is only base unit 6-step feedback.
Inputs
Channels A and B can be configured as inputs by setting NV Parameter
PosCmdSrc
to AQUADB. With NV Parameter
OpMode
set to Position and
PosCmdSrc
to AQUADB, the motor shaft position command comes from the
quadrature decode of channels A and B input scaled by the ratio of NV
Parameters
GearOut
over
GearIn
. In Input mode, Channels A & B accept
quadrature position commands. The command signals need to be differential
quadrature signals.
Channel A leading B generates a CW position command while Channel B
leading A generates a CCW position command. The magnitude of the
command position is set by
GearIn
and
GearOut
. The maximum input line
frequency for reliable operation is 625 kHz, which corresponds to a maximum
quadrature pulse rate of 2.5 MHz.