User's Manual

8 Fluke Corporation Concerned about arc-flash and electric shock?
It is good working practice to make labeling
clear and accurate; too much information is as
bad as too little. If a system has several access
points and arc flash hazards, label it with the
parameters for the greatest hazard.
The “live work” permit
Finally, before any work can commence, the
responsible manager must generate and sign an
energized electrical work permit. This describes
the task and why it must be performed with live
energized equipment, long with the shock and
flash boundaries plus related PPE.
Arc flash hazards and the electrical
thermographer
The goal of any electrical thermographer is to
prevent unplanned shutdowns in a manner that
is reliable, repeatable and above all safe. Since
thermographers work with the target equipment
online and on load coupled with the fact that
IR Cameras cannot “see” through panel covers,
thermographers face severe safety hazards
when attempting to scan electrical distribution
equipment.
Taking measurements with a cover removed is
not a safe option.
The ideal solution is the provision of a perma-
nent “access point” in the equipment housing
Leaving the cover closed:-
1. Increases safety.
2. Reduces the background reflection quotient
and reduces the interference making readings
more repeatable.
The safer alternative is the provision of a
permanent “access point” in the equipment
housing.
Ports, panes and windows
For infrared thermography, there are three types
of access point:
•
Infrared Port
•
Infrared Pane
•
Infrared Window
An IR port is simply a hole or series of holes; an
IR pane is a thin polymer optic. Both limit physi-
cal access (human contact) to live equipment.
However, in the event of an arc fault neither
option provides a protective barrier between the
thermographer and the exposed conductor and
arc flash source. A pane affords little protection
since it is a thin polymer with a low melting
point.
Figure 6. Energy level of 201 cal/cm² @7.2K V