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Test Equipment

Test Equipment
Test equipment for calibration, measurement, test of air velocity and flow, and monitor backflow, carbon monoxide, and combustion. Distance, electrical control signals, electricity, gas detection/analysis, ground and continuity meters are available. HVAC balancing, humidity, light, and many more are available.

QUESTIONS

Question
What is the advantage of using a manometer rather than a Magnehelic® gage?
Answer
Dwyer Instruments manufactures many different types and styles of manometers with various accuracies and prices for different applications as well as the Magnehelic® gage. For example, some of the many manometers we manufacture are Hook Gage Manometers with ±0.001 inches water column accuracy; Microtector® Portable Electronic Point Gage to ±0.00025 inches water column accuracy; Handheld Digital Manometers with ±0.5 inches water column accuracy; very inexpensive Mark II Molded Plastic Air Filter Gages at ±3% inches water column accuracy. The key point is that we offer many manometers and the selection depends on your specification, application, convenience needs and pocketbook. Some of the key factors to consider that affect manometer performance and usage are: Characteristics of Indicating Fluid, Readability and Leveling. You should read "Measurement of Pressure with the Manometer" in our catalog to fully understand the importance of these factors and their effect on your reading wit
Question
Why doesn't 1 inch on the scale of a 1223-12-D manometer equal 1 inch on a ruler?
Answer
The calibration scale on the manometer has been compensated for the specific gravity of red gage fluid which is less than water.
Question
Since water will not mix with oil, why can't a D-style manometer be used to measure water pressures?
Answer
The weight of the water itself is also being measured which results in erroneous readings.
Question
What are the principle advantages of red gage fluid over water for use in manometers?
Answer
Red gage fluid is slow to evaporate, won't freeze, is more readable and produces slightly expanded scales for better reading resolution.
Question
Will the water manometers freeze?
Answer
Yes, if the temperature drops below 32 degrees Fahrenheit, the fluid in the manometer will freeze. The fluid used in "W/M" style manometers is water-based with a small amount of fluorescent green fluid to enhance the meniscus. The other gage fluids have a lower freezing point, however, it is recommended that the manometers be stored above 32 degrees Fahrenheit.