Cutler-Hammer D320 PLC, User Manual

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D320 PLC User's Manual
Capacitive Load
When using a capacitive load, to reduce the effect of an inrush current, connect the protective circuit in
series with the load as shown in the figure below.
External Fuse
An external fuse can be used for overload protection. The fuse within the module is provided to
prevent damage in case of a short circuit on the output. However, the module fuse is not designed to
protect the terminal in case of an overload. It is recommended to attach an external fuse for each output
point, based on the particular application. Short circuits in certain types of loads can damage the output
module before the internal fuse blows. Be certain to provide the proper level of short circuit protection
for a given output type.
Leakage Current
When using an SSR output to a load that draws a very low level of current, leakage current in the SSR
output may cause a load not to turn Off. To prevent this problem, connect a properly rated resistance in
parallel with the load.
Installation Precautions for I/O Modules
I/O and Power Cables
•
Separate the wiring of the I/O cable and the power cable as far as possible. Do not put the two
cables through the same duct.
•
Leave 4 inches (100 mm) or more between the following:
I/O wiring
Power cable
High voltage cable
Output
Terminal
COM
Terminal
[Output Module]
Resistance
Load
Output
Terminal
COM
Terminal
[Output Module]
Load
Inductance
Output
Terminal
COM
Terminal
Load
Resistance
[Output Module]