What Are the Different Types of Load Cell Cables?

Responsible for channeling both power and communication between the load cells and the indicator, load cell cables are an integral part of building a custom scale. Though not just any cable will work. See, load cell cables are selected based on the distance between the two parts, as well as certain environmental conditions like temperature, contact with abrasive or flammable materials, or even rodents. 

Container truck on scaleBefore you can know the right type your custom scale project needs, it is best to have an understanding of the different types of load cell cables available. 

4-Wire Load Cell Cable

Perhaps the most common cable, the 4-wire load cell cable is used primarily for short distances. As its name suggests, this type consists of four wires: 

  • Power (excitation) +
  • Power –
  • Signal (output) +
  • Signal –

Once connected, the cable should run from the scale to the indicator display. These wires are calibrated and designed to handle the surrounding temperatures. Many custom scale projects use the 4-wire load cell cable since it is more affordable and suitable for most scales. However, should you need additional length or if your scale is in an unpredictable environment, you may need to reconsider the type of load cell cable you are using. 

6-Wire Load Cell Cable

Designed for longer distances and more difficult settings, the 6-wire load cell cable offers a lot more options. Again, as the name suggests, these load cell cables have six wires. They contain the four found above, as well as positive and negative sense wires. The long distances that 6-wire load cell cables cover can subject them to changes in resistance, temperature, and dips in voltage. The addition of these two sense wires helps to keep things flowing steadily.

Because they are not thermally compensated as the 4-wire load cell cables are, the 6-wires can be cut and used alongside other cables with no issue – making them perfect for larger commercial custom scale projects. 

Types of Load Cell Cable Shielding

While 6-wire load cell cables offer a lot of benefits when designing a project, it is important to note the surrounding environment and opt for shielding that will protect the cable from any outside environmental factors. Below are the most common types of load cell cable shielding.

Hostile Environment Cable

Hostile environment cable is best used in environments that are, well, hostile. Depending on where the scale is being used, the cables may come in contact with harsh or abrasive substances, such as fuel, ether, or even salt. Over time, these substances can damage the cables. 

Hostile environment cables are created with a polyurethane jacket that acts as a barrier against these damaging substances, keeping the cable safe and the scale running smoothly. 

Rodent Protection Cable

Rodents and their incessant chewing may seriously interfere with a scale’s functionality. If in an environment where there are rats, mice, or other pests, the load cell cable may become enticing – leaving you with hefty costs to replace some or all of the cable.

Rodent protection cable is a type of cable that protects against this pesky situation. The outside layer of the cable is a braided shield making it difficult to chew. And, as an added defense, it is coated with a chemical that will discourage them from wanting to ever take a second bite. 

Intrinsically Safe Cable

Flammable gases or liquids or generally hazardous materials can be damaging to load cell cables, requiring added security in the form of a jacket. For intrinsically safe cables, industry-standard blue double jackets are used to protect the cables from exposure to these dangerous materials. 

High-Temperature Cable

In environments where the temperatures fluctuate or reach extreme highs, load cell cables need an outer covering that will protect the wires regardless of how hot it gets. A high-temperature cable is designed with a fluorinated ethylene propylene (FEP) jacket that insulates the wires and can withstand the heat without getting damaged. 

Choosing the Right Load Cell Cable

Choosing the right load cell cable is important. If you would like to learn more about the different types of load cell cables or have questions about what would work best for your project, contact our sales department at (919) 776-7737. After all, at Central Carolina Scale, we have the largest inventory of load cell cables in the industry. 

What do you think? Airlines Might Weigh Passengers…

Subject: Aircraft Weight and Balance Control

Airlines could soon require some passengers to step on the digital weigh scale or provide their weight before boarding the airplane.

The initiative, which was described in a recent Federal Aviation Administration (FAA) advisory, attempts to provide new data on average passenger weights as the current numbers allegedly don’t reflect today’s higher obesity rates in the US. By adding this requirement, this would help aircrafts not exceed their allowable weight limit. Essentially, the FAA wants to determine how much heavier Americans have gotten over the past decade. 

If this becomes the new standard, the new mandates would require airlines to take surveys to establish average passenger weights for crew members, airline baggage and passengers.

Once they’ve chosen a traveler, an operator may determine the actual weight of passengers by having them step on a scale before boarding the aircraft. However, if that’s not an option, they’re urged to ask each passenger their weight, while making sure to add 10 pounds to account for clothing.

Of course when it comes weighing people in a public setting… privacy needs to be considered, which is why the FAA also provided guidelines on conducting the procedure in a way that protects passenger privacy.

They stipulate that the scale readout should remain hidden from public view while an operator should ensure that any passenger weight data collected remains confidential. Travelers have the option of declining to participate in any passenger or bag weight survey, per the guidelines.  You can read much more on this subject by viewing the original article

What do you think about this subject?  I guess it makes sense as long as the airlines do a good job with privacy and being discreet.  However, what happens if you total up all the passenger and baggage weight and it’s too much?  Are certain people asked to leave?  Well, whatever you need regarding this subject, we can provide you.  Bench Scales to weigh airplane passengers, Airplane Baggage Scales and more…   

 

Why Should I Consider a Truck Scale with Weigh Bar Weight Sensors inside?

Should I buy a truck scale with weigh bar sensors? The Avery Weigh-Tronix Weigh Bar® was designed to overcome the shortcomings of the traditional strain gauge load cell and to provide the end user with a rugged, highly reliable and linear load sensing device at reasonable cost.

More than twenty years of extensive use in industrial, farm and transportation applications has demonstrated that the Weigh Bar has met these requirements. The unique, robust design of the Weigh Bar is the primary reason for this success.

The Weigh Bar has proven itself over the past 20 years to be one of the world’s most robust weight transducers manufactured today with over 500,000 installations world-wide.

The IP67 Weigh Bar design provides inherent strength and overload protection, while also providing accuracy and high reliability. A significant contributor for this is the positioning of the gauges on the outside of the Weigh Bar. More robust than a shear beam load cell for a given output – a shear beam load cell will reach its peak fatigue point much sooner than a Weigh Bar.

Error Reduction

The unique design of the Weigh Bar allows simple calculations to be made by the indicator, eliminating several types of errors:

End Loading – When an end load is applied to the Weigh Bar, it is subjected to a
uniform compressive strain throughout its length – all sensors detect the same strain.
Torsion Effects – When torque is applied to the Weigh Bar, a uniform torsional shear strain is developed through the length of the bar – both sensors detect the same strain.
Side Loading – When a side load is applied to the Weigh Bar, it acts as a beam, but at a 90-degree angle. When this occurs, the neutral axis of the beam (the point in the beam where neither tension or compression occur) falls directly under the center of the strain gauges. No apparent strain is seen by the gauges.
Vibration –The fine grain structure of aircraft quality steel is resistant to vibration fatigue and induced error. The strain gauges and adhesive used are also vibration and fatigue proven.

Load Cells – The Avery Weigh-Tronix Weigh Bar® Weight Sensor

The exclusive Avery Weigh-Tronix Weigh Bar® is an extremely rugged, highly reliable, load sensing device. Over several decades, the Weigh Bar® has built a reputation for precision, reliability and durability that no other load cell can match.

Weigh Bar – Reduced cost of ownership 

Precision machined from aircraft quality, alloy steel, the Weigh Bar® offers excellent repeatability and long-term durability, reducing cost of ownership and need for load cell replacement.

Rugged Weight Sensors

With up to ten times more steel content than shear beams or compression cells, it absorbs impact to minimize peak forces and is virtually fatigue-proof. The Weigh Bar® is proven to resist electrical surges and is protected by a limited warranty that includes coverage against lightning damage.

Accurate Weigh Bar

The sensor’s design automatically cancels the effects of side loading, end loading and twisting, resulting in quick, accurate readings which are achieved regardless of temperature change, vibration, and shock loads on the scale.

Sealed “Load Cell”

The standard alloy steel Weigh Bar® is well protected against harsh environments by an exclusive 5-layer, sealing process. For the most challenging locations hermetically sealed stainless steel weigh bars are available.

avery weigh-tronix weigh bar

 

Features

Benefits

 

  • No mechanical restraints or stops

 

  • Less maintenance
  • Reduced physical damage
  • Lengthens the life of the weighbridge.
  • 500,000 in service over 20 years
  • Peace of mind with a proven design
  • Inherent lightning protection by design
  • Total reliability, less downtime
  • Impervious to end, side and torque loads

 

  • Consistent accuracy in arduous conditions
  • Faster weighing cycles
  • Prevents costly repairs and downtime
  • 5000 division accuracy as standard
  • 10 kg in 50 tonnes less give away at no extra cost
  • Completely sealed and airtight
  • Designed and tested to exceed IP67
  • Total reliability means less downtime

 

  • Protects cables from accidental damage and rodent attack
  • Prevents costly repairs and downtime
  • Weigh Bars mount off the ground

 

  • Out of the dirt and water, no need for costly stainless steel construction. Ensures a longer life