Ten facts about infrared windows

Infrared (IR) inspection is widely used and quickly becoming indispensable in electrical maintenance programmes. With the advent of IR windows, this procedure is now both safe and cost-effective. However, certain key aspects have to be considered in order to get the most out of a maintenance programme:

1. An IR window is a generic term used to describe an inspection point that is designed to allow infrared radiation to transmit to the outside environment. Simply, an IR window is a data collection point for a thermal camera.

2. An IR window will not provide shielding in case of an electrical explosion, also known as arc flash. It will however significantly reduce the likelihood of such an event due to electrical panels not being opened.

3. Wherever possible, use polymer rather than crystal windows. Crystal can shatter and is moisture absorbent, causing it to fail over time – not so with polymer.

4. Emissivity is one of the most important variables therefore, when installing IR windows, it is crucial to standardise the emissivity of the targets while the gear is open.

5. Every camera has a field-of-view defined in degrees across a horizontal/vertical axis. Obstructions, such as phase dividers or cables inside the cabinet may decrease actual field-of-view.

6. While equipment is de-energised, gather as much information as possible. Do a complete IR inspection at the end of the window installation in order to create a benchmark/baseline for future inspections.

7. The only standard that applies to the IR windows is the UL50; this is more of a classification than a standard. All other standards that are cited may have a bearing on some aspect, or use of a window.

8. IR windows allow inspections to take place with the cabinet panels closed, thereby not exposing personnel to energised components and elevated hazards/risks.

9. IR windows are safe to use and eliminate risk where possible. They provide a systematic approach to data collection during inspection and are cost efficient.

10. IR windows save time and money, which leads to a return on investment within the first or second inspection cycle.

By facilitating closed-panel inspections, the use of IR windows eliminates 99,9% of arc flash triggers and completely eliminates injuries caused by accidental human contact with energised equipment during infrared inspection. IRISS infrared windows are unique in the market, being made of polymer instead of crystal. They are shatterproof and can be manufactured in any shape or size.

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