Rockwell Automation 1753-L32BBBP-8A GuardPLC 1800 Controller - Manual (Page 14)

14 GuardPLC 1800 Controllers
Rockwell Automation Publication 1753-IN002C-EN-P - June 2010
Example: Connecting Actuators to the Outputs
High-speed Counter Connections
The controller features two independent high-speed counters. Both counters are 24-bit, are
configured for either 5V or 24V DC, and have a maximum input frequency of 100 KHz.
The counters can be used as a counter or as a decoder for 3-bit Gray Code inputs. As a counter,
input A is the counter input, input B is the counter direction input, and input Z is used for a
reset.
The counter inputs must be connected using shielded, twisted-pair cables for each measurement
input. The shields must be connected at both ends. The input lines should be no more than
500 m (1640 ft) in length. All L- connections are internally connected on the controller.
Cables are clipped to the shield contact plate when connecting counter inputs. Remove about
2 cm (0.78 in.) of the outer cable insulation so that the mesh is exposed at the point where the
cable is clipped to the plate.
TIP Inductive loads can be connected without a protection diode on the load.
However, Rockwell Automation strongly recommends that a protection diode be
fitted directly to the load to suppress any interference voltage. A 1N4004 diode
is recommended.
IMPORTANT Make sure that the mesh comes in direct contact with the shield contact plate.
If the mesh does not touch the plate, the cable is not grounded.
DO 1 DO 2 DO 7 DO 8 L- L-
…
63 64 65 66 67 68 71 72 69 70
net
T
4 Cable Clip
Mesh
Shield
Contact Plate