Force Measurement Cables and Connectors Guide

Unlike simple power or data transfer cables, force measurement cables and connectors are critical system components. They ensure accurate data transmission from the sensor, like a load cell, to the instrumentation device.

Choosing the right cable and connector is essential for the optimal performance of any measurement device. It depends on factors like the specific application, the environment where the cable will be used, the signal frequency and power requirements, and the types of measurement devices involved.

Interface offers a wide range of standard and custom cable assemblies for seamless integration with our force measurement products. These cables are built with high-quality components to maintain accuracy and reliability.

Sensor Interconnect Cable Assemblies and Connection Resources

The new Interface Sensor Interconnect Cable Assemblies Guide provides wire harness information for connecting transducers with receptacles to Interface indicators and other instrumentation.

A cable assembly is the vital link between your load cell and your measurement system. It’s engineered to transmit signals, maintain integrity, and ensure accurate measurements. Features like shielding to protect against interference, twisted pairs to reduce noise, and durable jackets to withstand environmental factors achieve this.

The new online guide provides detailed specification information for the Interconnect Cable Assembly for the following:

  • Sensor model
  • Sensor end plug type
  • Instrumentation end: pigtail, screw term, DE9P, Binder

The cable tool also highlights an Instrument Connection Selection Guide by model. Connect here to the guide.

In the new Interface Cables and Connectors Brochure, you can find additional specification details that are important when selecting a sensor and pairing it with an instrument, whether using an Interface instrumentation device or another product you use to gather and analyze data.

The Interface Cables and Connectors Brochure offers the following information to help you in identifying the right solution:

  • Cable Assemblies
  • Connectors
  • Electrical Information
  • Load Cell Integration Cables Type, Wire Size, Number of Wires, Shield, Description
  • Load Cell Cable Wiring Diagrams
  • Load Cell Connector Wiring Diagrams
  • Connectors

For high-accuracy force measurement, the effects of the cable on the measurement must be considered. For constant voltage excitation, there are two significant effects. These are an effect on the sensitivity due to voltage drops over the cable length and an impact on the thermal span characteristics of the load cell due to the change of cable resistance with temperature.

Essential Tips for Selecting a Cable

When choosing a cable, consider these key factors:

  • Length and Environment: Keep cables as short as possible to minimize signal loss. Ensure the cable is rated for the expected operating temperature range and consider waterproof options for wet environments.
  • Physical Characteristics: Select a cable with the appropriate flexibility for your installation. Stiffer cables offer more durability but can be harder to maneuver in tight spaces.
  • Signal Integrity: Shielded cables are essential in environments with electrical noise. Twisted pairs further improve noise rejection, especially in longer cables. Match the number of conductors to your load cell configuration (4-wire for basic setups, 6-wire for advanced measurements).

Cable Effects on Performance

Cable Length Effects

If the Interface load cell is sold with cables of any length, the sensitivity is determined by the installed cable during calibration. For load cells with connectors, there will be a loss of sensitivity of approximately 0.37% per 10 feet of 28 gage cable and 0.09% per 10 feet of 22 gage cable. This error can be eliminated if a six-wire cable is run to the end of the load cell cable or connector and used with an indicator with sense lead capability.

Temperature Effects

Since cable resistance is a function of temperature, the cable response to temperature change affects the thermal span characteristics of the load cell cable system. For 6-wire systems, this effect is eliminated. For 4-wire cables, the effect is compensated for in the standard cable lengths offered with the load cells if the load cell and cable are at the same temperature simultaneously. For non-standard cable lengths, there will be an effect on thermal span performance. The effect of adding 10 feet of 28 gage cable is to cause a decrease in sensitivity with a temperature equal to 0.0008%/°F (an amount equal to the standard Interface specification).

For an added 10 feet of 22 gage cable, the effect is to decrease the sensitivity by 0.0002%/°F (one-fourth Interface spec). Customers can often tolerate the degraded performance since our standard specification is extremely tight. However, this can be a significant factor for long cable runs or high-accuracy applications. In such cases, the best approach to the problem is to run six wires to the end of the standard cable length and sense the excitation voltage, eliminating the problem.

Wireless vs. Cable

While wireless solutions are becoming more common, carefully evaluate your needs before “cutting the cable.” Consider sensor compatibility, potential accuracy impacts, power limitations, and environmental challenges. If you are considering cutting the cable, review all the options for our Wireless Telemetry System to ensure you have the right connections via wireless or Bluetooth connectivity.

Application-Specific Considerations

Different applications have unique cable demands. For example, oil and gas applications may require specialized cables for extreme temperatures and pressures, while submersible applications need sealed connectors to prevent water damage.

Interface Accessories

Interface provides high-quality accessories, including custom solutions, to meet your needs. Our engineers can assist you in selecting the right cables and connectors for your application, ensuring accurate and reliable force measurements.

To learn more about our cables, visit our accessories.

ADDITIONAL RESOURCES

Cable Assemblies 101

Understanding Cable Length and Temperature Effects

Decoding Sensor and Instrumentation Communication Protocols Webinar Recap

Load Cell Connection to USB Instrumentation Advances Measurement Applications

Interface Instrumentation Connects Sensors to Actionable Data

Cable Assemblies

System Level Calibration

Cables and Connectors Brochure Pages