These air-cooled extensometers are for testing a wide range of materials, including metals, plastics, composites and ceramics. All will work in both tension and compression. The dual flexure design makes them very rugged and insensitive to vibrations and permits higher frequency operation. These units are air-cooled for elevated temperature use. A supply of dry air or inert gas must be available at approximately 2-2.75 bars (30-40 psi). For low temperature testing, no cooling is used.

The extensometers come standard with Epsilon’s quick attach kit, making it easy to mount them on the test specimen. The Model 3742 extensometers are strain gaged devices, making them compatible with any electronics designed for strain gaged transducers. Most often they are connected to a test machine controller. The signal conditioning electronics for the extensometer is usually present or may often be added. In this case the extensometer is shipped with the proper connector and wiring to directly plug into the electronics. For systems lacking the required electronics, Epsilon can provide a variety of solutions, allowing the extensometer output to be connected to data acquisition boards, chart recorders or other equipment.

• May be left on through specimen failure.
• Full bridge, 350 ohm strain gaged design for compatibility with nearly any test system.
• All models can measure in both tension and compression and can be used for cyclic testing.
• Mechanical overtravel stops in both directions.
• All units meet existing ASTM class B-1 and ISO 9513, class 0,5 requirements for accuracy.
• Hardened tool steel knife edges are easily replaced. A spare set comes with every extensometer.
• Includes high quality foam lined case.
• Rugged, dual flexure design for strength and improved performance. Much stronger than single flexure designs, this also allows cyclic testing at higher frequencies.

Excitation: 5 to 10 VDC recommended, 12 VDC or VAC max.

Output: 2 to 4 mV/V nominal, depending on model

Linearity: 0.10% to 0.15% of full scale measuring range, depending on model

Temperature Range: Standard is -195 °C to +300 °C (-321 °F to 572 °F)

Cable: High temperature cable, including air cooling hoses

Standard Quick Attach Kit: Fits round samples up to 0.5 inch diameter (12 mm) and flats to 0.5 inch thick by 1.0 inch wide (12 mm by 25 mm)

Operating Force: <50 g typical