The design of the HEL3700 test meters from Thor Helical Australia incorporates an integral bridging unit that houses a mechanical pulling arrangement fitted through a hydraulic load cell. These meters also have a displacement indicator and a pressure gauge which directly measures the load applied to the helical tie.

Testing is done by means of a test key which fits into one of two available openings and winds onto the tie. The jaws of the key bite into the tie when the device is subjected to an axial load.

HEL3700 test meters are precise measuring units and they come in a robust protective case. It is important to the continued reliable and accurate functioning of these devices that they receive routine maintenance and care. Both the piston rim and load stud should be kept free of dirt, the central load stud should be kept lightly lubricated and the device should be kept in its protective box when not in use.

It is also extremely important when using these test meters to not exceed the maximum load capacity. The device should not be used continually for periods longer than 30 minutes and should not be exposed when under maximum load to extreme increases in temperature. For example prolonged exposure to intense sunlight.