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Other devices. Checking low-voltage batteries ensures proper connections and identifies poorly attached cell strap connections in a battery string that may heat up enough to burn posts and create hazards. You can spot heat buildup in lighting ballasts before they start to smoke. A large UPS has hundreds of battery connections, all prone to loosening and corrosion. You can also look for cold spots in the UPS, which may indicate an open DC filter circuit
Selecting the right tool
When choosing an IR thermometer for electrical maintenance, consider the size of the targets you monitor, their distance from where you'll monitor them, the temperature ranges to cover, whether you want laser sighting and variable emissivity settings, and your budget. Let's look at each of these, starting with cost.
IR thermometers suitable for electrical maintenance range from under $99 (basic models without laser sighting) to over $1200 for more sophisticated models with built-in data logger and a host of advanced features.
We express the optical resolutions of IR as a distance-to-spot size (D:S) ratio. To get the D:S, simply pide the distance (from the object to the thermometer) by the size of the spot you're measuring. The D:S is critical, because accuracy requires your target to be at least as large as the diameter of the spot you're reading. The object should fill the sensor's field of view. You need to position the object so background infrared radiation doesn't enter the optics' field of view (Fig. 2, in original article). So, base your choice of IR thermometer on how far the instrument will be from the target and the size of the target.
Select an instrument with a temperature range most closely matching your application range. Some instruments measure temperatures as low as 125DegrF (132DegrC) for subzero applications. Others measure temperatures as high as 5400DegrF (3000DegrC) for specialized applications involving metals and glass.
Most users opt for laser sighting. Some of the newest models even offer a multi-point laser sighting circle with center aiming point to delineate the precise area you're measuring. Other options include such features as data storage. Some IR thermometers can store readings for later downloading to a computer. Make sure to use your IR thermometer on a regular basis..
Conclusions
The uncertainty evaluation in this study included the Type A uncertainty for standard deviations of replicates or predicative uncertainty of calibration and the Type B uncertainty for reference temperature, nonlinear and repeatability and resolution source. The ambient temperature variation effect was excluded. The uncertainty sources of different operators or different parts of human body were not discussed in this study. The uncertainty analysis has become the basic information for the instrument. No literature or related reports were found that mentioned the evaluation of infrared tympanic thermometers. The method of uncertainty calculation for two types of infrared tympanic thermometers in this study has been developed. This method could be applied for other infrared thermometers.
In this study, tympanic membrane thermometry was as reliable and as accurate as axillary mercury glass thermometry. Thus, tympanic membrane thermometry can be used in the clinical practice, because it is easy to use and the speed of obtaining the temperature reading.
So, you measure with an IR thermometer and see temperatures you don't like. But how do you know if you really have a problem? The answer lies in the combination of published rating information and personal experience. Electrical equipment manufacturers normally define maximum permissible operating temperatures, frequently listing this on the equipment's rating plate.
The real benefit comes from having temperature histories for your equipment. Recording and trending temperatures will allow you to see when a problem is beginning. Catching problems before symptoms are obvious is the best way to keep expenses and downtime to a minimum.