Rockwell Automation 57C421B Pulsetach Input Module/DCS 5000/AutoMax - Manual (Page 17)

3Ć3
Step 7. You may need to add termination resistors to installations
where the twisted pair cable length from the pulsetach to
the module exceeds 200 feet. The resistor value should
be selected dynamically to provide the proper waveform.
See figure 3.2 for typical termination resistor connections.
For 5 VDC inputs, the termination resistors connect
between:
D terminals 12 and 14 (input A)
D terminals 15 and 17 (input B)
D terminals 18 and 20 (input Z).
For 12 VDC inputs, the termination resistors connect
between:
D terminals 2 and 14 (input A)
D terminals 3 and 17 (input B)
D terminals 4 and 20 (input Z).
When a pulsetach is wired for openĆcollector operation,
the termination resistors should be placed as shown in
figure 3.3.
Step 8. Insert the cable assembly's (M/N 57C372) field terminal
connector into the mating half on the module. Use a
screwdriver to secure the connector to the module.
Note that both the module and the field terminal
connector are equipped with keys" as shown in figure 2.1.
These keys should be used to prevent the wrong cable
from being connected to a module in the event that
connector needs to be removed and then reĆattached
later.
At the time of installation, rotate the keys on the module
and the connector so that they can be connected
together securely. It is recommended that, for modules so
equipped, the keys on each successive module in the
rack be rotated one position to the right of the keys on
the preceding module.
If you use this method, the keys on a particular connector
will be positioned in such a way as to fit together only
with a specific module, and there will be little chance of
the wrong connector being attached to a module.
Step 9. Check the wiring and be sure all connections are tight.
Step 10. With the pulsetach disconnected from the motor, apply
power to the rack and the pulsetach. Use an oscilloscope
to test the signal from the pulsetach. The signal at the
terminal strip should be a clean square wave of 5 or 12
volts.
Step 11. Verify the installation using the Programming Executive
software. Refer to the AutoMax Programming Executive
manual for more information.
Select the I/O Monitor function. For local I/O, enter the
slot number and register number (0Ć7) of the Pulsetach
module. For remote I/O, enter the slot number of the
master Remote I/O module, the remote I/O drop number,
the slot number of the Pulsetach module, and the register
number (0Ć7).