Honeywell HPM, Service

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2 Equipment Description
2.20 24 Vdc Fuse Protection
R688 HPM High-Performance Process Manager Service 101
December 2020 Honeywell
2.20 24 Vdc Fuse Protection
Card file fusing
Fuse protection is provided for the four types of card files. The following protection philosophy applies
for both the 7-Slot, 15-Slot, and IOP Only card files.

The individual IOP card and an associated standard FTA are protected by a common fast-action
fuse that is located on the backpanel. The fuse has a 2 A rating.

In addition to the 2 A protection, each individual IOP card has fast-action 0.5 A fuse protection that
is located on the card. The fast-action 0.5 A fuse is soldered in place and is not field replaceable.
You must replace the IOP card.

Both HPMM cards, High-Performance Communications/Control and High-Performance I/O Link,
and the HPM UCN Interface module are protected by a fast-action 3.2 A fuse that is located on the
High-Performance I/O Link card. The fuse is field replaceable.

A fast-action 2.0 A fuse protects the LLAI optical coupler module on backpanel U1. It generates
the line frequency phase reference signal that is used by LLAI IOPs.
Fuse removal
A Honeywell designed fusepuller is generally needed for extracting and inserting fuses in the HPM
backpanels because of the restricted space between components. The Honeywell part number is
51190586-100.
The fusepuller is comprised of three parts; an inner barrel that grasps the fuse, an end cap that is attached
one end of the inner barrel, and an outer barrel in which the inner barrel moves.
The following extraction and insertion procedures should aid in the use of the fusepuller.
Fuse extraction
Use the following procedure to extract a fuse from an HPM backpanel.
Step Action
1
Hold the outer barrel of the fusepuller with the fingers of one hand and depress the the
fusepuller’s end cap with your other hand.
2
Place the protruding end of the inner barrel around the fuse. The fusepuller must be
perpendicular to the backpanel.
3
Release the end cap while still holding the outer barrel.
4
Move the outer barrel towards the backpanel. The greater the movement, the greater the
gripping force will be on the fuse.
5
Extract the fuse from the backpanel by vertically moving the fusepuller away from the
backpanel. Depress the end cap to release the fuse.