Rockwell Automation 2755-DM9, -DM9E High Speed Decoder - Manual (Page 132)

Chapter 9
Maintenance and Troubleshooting
9–2
The power input module fuse protects the decoder from current overloads.
The fuse is located next to the power cord connector. To replace the fuse:
1) Disconnect the power from the decoder.
2) Try to determine which component is faulty (check cables for shorts).
Since the decoder contains no user serviceable components, you can only
isolate the problem to the scan head, cables, or decoder. Disconnect the scan
head cable from the decoder and replace the fuse as described below. If the
fuse blows again without the scan head, the problem is with the decoder. If
fuse blows again when scan head is reconnected, the problem is with the scan
head or scan head cable.
3) Use a small screwdriver to remove the power input fuse module. The
input fuse module is located next to the power cord connector. Pry on the tab
provided using the small screwdriver. The fuse module will slide out. Refer
to Figure 9.1.
4) Remove fuse holder from the fuse module.
5) Remove and install new fuse: 250V, (1 amp, slow blow), 5 x 20 mm or
3AG.
6) Insert fuse holder into fuse module and reinstall fuse module into the
decoder.
7) Apply power to verify operation of the decoder.
89–175–1
Figure 9.1
Power Input Fuse
Power Input Fuse Replacement