LEFM 3xxCi User Manual
IB1406 Rev 12
Section 7
Page 49
February 2017
5.
Locate the IOP/F25 fuse. (Note – the fuse protects the electronics from errant wiring of power to
120/230 VAC). The F25 fuse is on the same side of the IOP board as the plug in connectors, near
the power inputs (TB1). Refer to Figure 7.3 below.
Figure 7.3 Location of IOP/F25 Fuse
6.
Remove the F25 fuse with tweezers or needle nose pliers. .
DC Option: Only use Littelfuse Series 454 part number 0454-005 (5 amp rating) as a
replacement fuse. Skip to step 8.
AC Option: Only use Littelfuse Series part number 37412000430 (2 amp rating) as a
replacement fuse. Skip to step 8.
7.
Remove the new IOP from its packaging. Place the old IOP into this packaging for proper storage.
8.
Align the IOP with card guides. Slide the IOP down the guides until it engages the connector of the
CTC. Firmly push the IOP so that the connector seats (DO NOT FORCE).
Again, see Section 7.5 for removal/reinstallation of the enclosure’s front cover. For later models,
there is a metrological seal that needs to be reinstalled to connect the IOP to the CTC (plastic
wire).
9.
Viewed from the back, tighten the screw that holds the IOP to the enclosure.
IOP with AC Power Option
Location of
F25 Fuse
IOP with DC Power Option
