Rockwell Automation 1746-XXXX SLC 500 Digital I/O Modules Installation Instructions - Manual (Page 8)

8 SLC 500 Digital I/O Modules
Publication 1746-IN027D-EN-P - December 2012
Fuse Protection (1746-OAP12 modules)
A fuse is provided on each common of the 1746-OAP12 module (shown on Location of
Jumpers and Fuses for 1746-OAP12 Module on page 10 ) for a total of two fuses. The fuses are
designed to protect the module from short-circuit conditions. The fuse does not provide
overload protection. In the event of an overload on an output channel, it is likely that the fuse
will not blow and the output device associated with that channel will be damaged. To provide
overload protection for your application, user-supplied fuses should be installed externally.
The recommended fuse for overload protection is SAN-O HT. Select the fuse rating according
to your load. Do not use HT fuses rated higher than 2.0 Amps.
Blown Fuse Diagnostics
If the fuse blows on the 1746-OBP16, 1746-OVP16, or 1746-OAP12 module, the following
occurs:
• The blown fuse LED indicator will illuminate, provided power (5V DC via backplane
and load power via external supply) is applied to the module.
• A processor error will occur if JP1 connects pins 2 and 3. (See figures on page 9 and
page 10 .)