MNM Scales 20,000 lb Load Cell for Cable & Wire Rope Tension Testing

pete8781
Jul 29
4 min read

Need more details or help with a cable-tension measurement setup? Call MNM Scales at (832) 290-3120 or email mnmscales@yahoo.com.

The MNM Scales 20,000 lb load cell for cable and wire rope tension testing is a high-capacity inline force-measurement system for shops, test facilities and industrial users that need to know how much tensile force is actually carried by a cable, wire rope, chain or similar load path. S-beam load cells are widely used in tension-testing and cable-measurement applications because the sensor can be installed directly in line with the force instead of trying to infer tension indirectly.

Crane-20k S-beam load cell system for wire rope cable and chain tension measurement

How an Inline S-Beam Measures Cable Tension

The MS-1-20K is a tension/compression transducer. When it is placed inline with a test specimen and tension pulls along the load cell’s primary axis, strain gauges inside the sensor create an electrical signal proportional to the applied force. The Crane-20k indicator converts that signal into a readable force/weight value. That same basic principle is used in cable-testing machines, tension-monitoring fixtures and material-test stands across the test-and-measurement industry.

This is different from a clamp-on wire-rope tensiometer that estimates tension from rope deflection. With an S-beam, the sensor becomes part of the force path. For a cable, chain or wire-rope test, the fixtures connect the specimen to the load cell so the measured tensile force passes through the cell directly.

Technical Performance for Tension Testing

The Crane-20k system is rated 20,000 lb x 1 lb. The underlying MS-1-20K publishes a 3.00 ± 0.01 mV/V rated output, ±0.02% full-scale nonlinearity, ±0.02% full-scale hysteresis and ±0.01% full-scale repeatability. Those figures matter in a repeatable tension test because they describe how closely the sensor follows a straight response, how much response can differ when force is approached from different directions, and how consistently it reproduces a measurement under similar conditions.

The load cell also specifies ±0.02% full-scale creep over 30 minutes, a compensated range of -10°C to 50°C, an operating range of -20°C to 60°C and 120% full-scale safe overload. Use 20,000 lb as the system’s planned measurement ceiling; the overload figure should not be treated as a usable test range.

Cable and Wire-Rope Test Applications

A high-capacity inline load cell can support pull-force characterization of cable assemblies, wire-rope test fixtures, chain assemblies, winch lines, fabricated tension members and other components in a controlled test environment. It can be used to compare samples, document a force at a defined extension or test condition, observe breakaway or peak force, verify repeatability after a production change, or feed force data into an engineering validation process.

It is especially useful when the application needs a digital local readout and the operator wants to capture a maximum force rather than continuously watching the display. Peak Hold can retain that maximum observed value, while RS232 gives integrators a path to compatible external recording equipment.

LP7515 digital indicator for cable wire rope and chain tension testing with S-beam load cell

Alignment Is Critical in a Tension Fixture

The load should enter and leave the S-beam along its central axis. A fixture that pulls at an angle can introduce side loading and bending, which are not the force components the S-beam is intended to measure. Clevises, rod-end bearings and other appropriately rated hardware can help a fixture self-align. The specimen itself also needs to be gripped in a way that does not slip, cut the cable, or introduce a misleading geometry.

LP7515 load cell wiring diagram for 20,000 lb cable tension test fixture

What Data Should You Record?

Depending on the test objective, useful data can include pre-load, maximum tension, steady tension, force at a specified displacement, force after a dwell period, repeated-cycle values and the difference between multiple specimens. If tests are meant to be compared, keep fixture geometry, attachment hardware, loading rate and environmental conditions as consistent as practical. Force measurement is only one half of many material or assembly tests; displacement, time, cycle count and failure mode may also be important.

Frequently Asked Questions

Can the Crane-20k measure wire-rope tension?

Yes, when the wire rope or cable is connected through an engineered inline test fixture so its tensile force passes axially through the S-beam.

Is it a clamp-on cable tension meter?

No. It is an inline S-type force sensor system. It measures tension through the sensor rather than estimating tension by clamping onto and deflecting an existing cable.

Can it capture the maximum force in a pull test?

Yes. Peak Hold is one of the useful indicator functions for capturing a maximum during a controlled pull.

Can it be used for destructive testing?

The sensor can measure force in a properly designed test stand, but destructive tests store substantial energy and require an engineered fixture, guarding, rated hardware and a procedure that protects the sensor and personnel. Keep applied force within the system rating even if the specimen is intended to fail.