Category Archives: Load Cells

QUESTIONS TO CONSIDER BEFORE PURCHASING A TRUCK SCALE

Posted on by


Over the next few blog entries, we are going to take a look at a few of the reasons why Cardinal’s ARMOR® Digital Truck Scale arguably provides the best return on investment.

Cardinal Scale’s all-around innovative truck scale and load cell design
provides the most protection against circumstances—seen and
unforeseen. The combination of Cardinal Scale’s SmartCell® load cells,
ARMOR® weighbridge, and axis® frictionless centering system provide
a well-rounded vehicle scale package that protects against the
harshest conditions while transmitting valuable weight data digitally.
Cardinal Scale provides customers with the versatility and efficiency
required to fit their individual scale needs while saving valuable time
and effort.

Cardinal Scale engineers, develops, and manufactures their truck
scale hardware, software, and load cell technology in one location.
Weighbridges, indicators, load cells, and related instrumentation
are produced to meet the individual customer’s needs. Due to the
highly-vertically-integrated nature of Cardinal Scale’s manufacturing
processes, the company can easily modify and customize each truck
scale they make to fit a customer’s application—a benefit that is
becoming increasingly rare in today’s truck scale market.

Keeping with its visionary heritage, Cardinal Scale has again pushed
the boundaries of truck scale technology by developing SmartCell®
digital load cells. The added benefit of transmitting weight digitally
is greatly augmented by Cardinal Scale’s iSite remote monitoring
system. Dealers can now see, in real time, load cell issues as they
happen. Most importantly, time spent checking load cell wiring
is greatly reduced thanks to the streamlined, digital load cell
diagnostics. Dealers can now quickly and remotely diagnose load cell
issues and replace defective load cell elements in a fraction of what
analog load cell diagnosis requires.

Carefully consider the following questions for the purchase of a truck
scale to see if Cardinal’s ARMOR® digital truck scales will provide the
best solution for your time and resource investment.

Impacts That Factor in the Price of a Truck Scale?

Posted on by

A couple of years ago we discussed the ever popular how much does a truck scale cost? Today, we answer a similar question. What factors impact the price of a truck scale?

When purchasing a large piece of equipment, such as a truck scale, it can be hard to look past the price tag. However, to ensure you are investing in quality equipment that will last your business a generation or more, it is important to understand the factors impacting total purchase price. Elements such as design, craftsmanship, components and foundation of a truck scale all impact the final purchase price.

Truck Scale Design

Although the weighbridge (the structural body of a truck scale) can have varying designs depending on the manufacturer, it performs the same basic function across all brands and models: weighing trucks. Manufacturers who use a wide flange I-beam weighbridge design often have a higher steel content in their truck scales than manufacturers who utilize bent plate or steel tubing designs.

The number and size of beams in a weighbridge can also impact steel content. Designs that place larger beams closer together offer more support for vehicles than designs with smaller beams placed further apart. The support from larger beams means the deck won’t bend as easily, so the truck scale will provide accurate weighments for a longer time.

To better understand the cost of the truck scale steel content, divide the cost of the scale by its shipping weight to get the price per pound of the scale. This can be used to compare the price per pound of similar scales from different manufacturers. You may find the scale with higher steel content actually costs less on a price-per-pound basis.

Value in Scale Quality

Quality craftsmanship also contributes to a truck scale’s integrity. Purchasing from a company that invests in engineering and manufacturing ensures that there is a highly skilled team behind each and every truck scale.

The components that make up a truck scale are just as important as the team behind it. Companies who take the time to source high-quality load cells, steel, cables and other components often have a higher quality product.

Truck Scale Installation

The installation of the truck scale will also impact the final price. Installation includes excavation, the cost to pour the concrete foundation, off-loading and positioning the scale, installing electronic components and performing the initial calibration of the scale.

The truck scale installation should be performed by professional scale technicians who have experience working with scales from the manufacturer you chose. This expert installation will ensure proper scale operation and reliable weighments over the life of the scale.

A truck scale is a significant investment, and design, quality and installation all impact the final price of a truck scale. Choosing a truck scale with a heavy-duty design, superior engineering and components backed by industry experts gives you a scale that will last for a generation or more.

For more information on purchasing a truck scale, please contact the Central Carolina Scale heavy capacity sales department by calling (919) 776-7737.

Answering Your Questions About Truck Scale Load Cells & Mounting Systems

Posted on by

The majority of this article is provided by Rice Lake Weighing Systems. We have also added a few insights and thoughts of our own as well.

What is a Load Cell?

A load cell, also commonly referred to as a transducer, converts a mechanical force into an electrical signal. Basically, the load cell bends slightly when weight is applied.

In a compression mounted load cell where the load cell is beneath the weighing vessel, like a truck scale, the load cell compresses when a load is applied. This would apply to scales like the Cardinal PRC which has the SCA load cells.

The load cell produces an analog output signal that is proportional to the applied weight or force. The load cell transmits this signal to a digital weight indicator that converts the signal into a digital weight measurement.

When an application requires multiple load cells, each load cell should measure the same proportion of the total load. So in a four load cell system, each load cell should measure exactly one quarter of the load.

Many load cells are proprietary to a specific manufacturer, and may require additional maintenance and costs of ownership. Carefully discuss with your scale supplier all options for load cell systems.

replacement rl75058-75k truck scale load cells

Analog Load Cells
The most common load cells on the market work on the strain gauge principle. All load cells need to convert their analog values to digital before the load’s weight reading can be displayed on an indicator.

Some load cells are directly cabled to the digital weight indicator where the translation occurs. Other cells are connected to summing junction boxes on the scale where the box sums analog readings from multiple load cells, converts it to a digital signal and sends that signal to the digital weight indicator.

Hydraulic Load Cells (pressure transmitters)
Unlike most other load cells, hydraulic load cells do not use strain gauges or internal circuitry. Instead, hydraulic load cells contain hydraulic fluid, and during compression, a change in pressure is created and transmitted via tubing to a summing system where the pressure is applied to an analog load cell to determine weight.

The advantages of the hydraulic load cell typically relate to being resistant to lightning damage. The disadvantage of this type of scale and replacement load cell is the cost.

Analog-to-Digital Load Cells
Some analog load cells perform the analog-to-digital signal conversion within the load cell housing. Although sometimes referred to as digital load cells, the cell still measures in analog. Making the conversion from an analog signal to a digital signal in the load cell allows the system to compare the output of individual load cells and perform a diagnostic analysis based on that information.

Some would say that because the conversion happens in the load cell, sensitive electronic components are increased throughout the scale system, making them susceptible to damage from vibration, moisture and increased solder joints.

Types of Load Cells Found in Truck Scales

Double Ended Shear Beam
This is the most widely used vehicle scale load cell configuration in North America. A double-ended shear beam load cell is a compression load cell that offers a large capacity range from 1,000 to 200,000 pounds.

The double-ended shear beam is secured at both ends with the load applied to the center of the load cell. As in all shear beam designs, the strain gauges are mounted on a thin web in the center of the cell’s machined cavity.

The load cell also has the advantages of being less expensive in high capacity applications than the canister load cell because it does not require checking, making it virtually a maintenance free solution.

Canister
A canister load cell is the oldest load cell type. Also a compression device, it is shaped like a vertical canister and can handle loads from 100 to 1,000,000 pounds.

It is either hermetically sealed or welded to protect the gauges. This load cell’s drawbacks include the fact that it requires checking — installing check or stay rods to hold the weighing vessel in place on the load cell’s top plate during weighing.

For these reasons, many canister load cells on the market today are used to replace older canister load cells on existing weighing systems.

Rocker Column
Some manufacturers prefer rocker column load cells because they are inexpensive. However, they require check rods and bumper bolts that require maintenance, increasing your cost of ownership. The cost saved by the manufacturer on the raw material is passed down the line to the end user in the form of additional maintenance.

Load Cells Are Usually Manufactured as either Alloy Steel or Stainless Steel 

Truck scale load cells are generally made of stainless steel or alloy steel, but most manufacturers offer a variety of load cell solutions that best fit your application needs.

Alloy Steel Load Cells
Load cells manufactured from tool alloy steel elements are by far the most popular cells in use today. The cost to performance ratio is better compared to either aluminum or stainless steel designs. The most popular alloys are 4330 and 4340 because they have low creep (the change in load cell output over time while under load) and low hysteresis (the difference between load cell output readings for the same applied load).

Stainless Steel Load Cells
Stainless steel cells are more expensive than tool alloy steel load cells. They are sometimes fitted with hermetically sealed web cavities, which make them an ideal choice for corrosive, high-moisture applications. Stainless steel load cells that are not hermetically sealed have little advantage over comparable cells constructed of tool alloy steel, other than a higher resistance to corrosion.

We hope you enjoyed learning more about the different load cells found in the average truck scale. Since 1980 we have been providing customers throughout the central part of North Carolina with truck scale inspections, scale repair and calibration services. Our test weights and weight cart are certified by the state of North Carolina for accuracy. Our scale technicians are highly trained and knowledgeable when it comes to checking and installing various brands of truck scales.

If you need your existing scale checked or perhaps you’re in the market for a new truck scale, please give us a call today (919) 776-7737.

 

Brewery and Beverage Manufacturing Equipment Co. Uses Cardinal Scales in Process and Packaging

Posted on by

In the case study below, we take a look at how a brewery and beverage company that manufacturers equipment for that industry, uses Cardinal Scale equipment in its process. The company that is featured in the case study chose Cardinal products for various reasons, one important reason was the wide range of products that Cardinal offers which allowed the company to utilize Cardinal Scale products throughout and not have to contend with multiple different brands of scales.

Cardinal 190 indicator

The systems provided by IDD provide answers for operations such as keg cleaning, sanitation and filling, flash pasteurization, bottling, and their HEBS (High Efficiency Brewing System). IDD manufactures these intricate and precise equipment systems to meet the distinct needs for their many customers in the beverage industry.

IDD’s reach extends all over the world. While primarily servicing America and Canada, IDD Process and Packaging, Inc. ships to Western Europe and as far as countries in the Oceania area, such as Australia. The burgeoning craft brewery and distillery movement in America and Canada provides IDD with a great deal of business opportunities; however, they are not limited strictly to beer and spirits. IDD delivers expertise in more traditional beverage production, such as grape juice, to more exotic and contemporary drinks, like kombucha and cold-brew tea.

To round out the design of a few of their systems, owner Jeff Gunn researched scale manufacturers to compare products lines and breadth of products. Cardinal Scale was capable of providing the load cells he preferred, along with the digital weight indicators meant to complete filling functions for keg, grain, and yeast managements systems, plus the scales themselves. “Cardinal Scale provided all of the implements that I needed within one company, and that influenced my decision to go with them,” said Gunn.

Cardinal Scale products are featured in Squire Keg Systems, Grain Handling Systems, and Yeast Management Systems. For the Squire Keg series, Cardinal Scale’s model EB-300 scale is coupled with the 190 STORM indicator. The EB-300 weighs the keg that can be moved on a roller platform, and the 190 provides the weight preset programming that is invaluable to precision filling. The Squire Series system can fill up to 30 kegs per hour.

The Grain Handling Systems and Yeast Management Systems utilize Cardinal Scale’s 825 or 225 weight indicator and the company’s TCBSS1KM-4 load cell kits. The TCBSS1KM-4 load cell kits provide the durability and precision needed to take on filling of grain augers, mills, and hoppers or multi-tank yeast propagation systems. The 825 or 225 weight indicator guides the more complex filling functions associated with the aforementioned tanking systems.

So as you can see, the robust product features of the Cardinal Scale Manufacturing lineup of products was a key ingredient in the success of the featured company in the case study. With more than five years of business between the two entities, both the companies are poised to achieve even more success in the beverage industry.

You too can enjoy this same level of success for your business. Contact our sales department to discuss adding load cells under your tanks or adding digital weight indicators to your scales that can collect data that you can then analyze in a spreadsheet on the computer.  Call (919) 776-7737 to get started.

Food Safety Modernization Act (FSMA) and Digital Scales

Posted on by

Food safety is extremely important to all of us. In today’s ultra competitive and fast paced world, it’s imperative that we have laws in place to ensure that the food we eat is as safe as possible.

We hope the article below helps you better understand information about the Food Safety Modernization Act (FSMA). Ultimately we think this information will highlight the ability of Rice Lake’s washdown products to meet your requirements of commercial processing industries. The FSMA info below not only informs producers about how to meet compliance laws, but demonstrates how Rice Lake scales can help prevent food contamination by the integrity of their construction and design.

For all producers, from the farm to the table, purchasing equipment that meets Sanitary Design Principles (SDP) is considered a mandatory preventative measure by the FDA. Our product offerings that are microbiologically cleanable, hermetically sealed and compatible with hostile environments can greatly assist you in adhering to these strict guidelines.

On January 4, 2011, President Obama signed the FDA Food Safety Modernization Act (FSMA) into law. The FSMA brought a much-needed focus of food safety laws into the food processing industry as well as to consumers, and the general public as a whole.

The signing of the FSMA was arguably the largest reform to food safety in the previous 70 years. According to the U.S. Food & Drug Administration (FDA), the FSMA “aims to ensure the U.S. food supply is safe by shifting the focus from responding to contamination to preventing it.” The key focus being prevention versus reaction in regards to food safety, from all aspects and stages of food—from the farm to the table.

The FSMA was spurred into action from an increase in foodborne illnesses in the U.S. The Centers for Disease Control and Prevention report almost 1 in 6 Americans fall ill to food borne diseases each year. Foodborne illness became an issue of public health in the early 2000s, enabling the FDA to set higher preventative standards for food safety and elicit enforcement agencies to hold companies to these standards and contain any potential problems before they become a widespread risk of foodborne illness. To do this, the FDA under the FSMA can order companies to recall when needed.

The primary role of the FSMA is prevention. As noted by the FDA, “for the first time, FDA will have a legislative mandate to require comprehensive, science-based preventative controls across the food supply.” This legislative power ensures all U.S. companies that contribute to the food supply, no matter their size, are subject to the authority of the FDA and their preventative and responding agency.

Under the Prevention section of the FSMA, controls are given to the FDA for the following:

• Mandatory preventive controls for food facilities
• Mandatory produce safety standards
• Authority to prevent intentional contamination

These measures need to be qualified by scientific justifications by the FDA and are enforced by legislation. Under the mandatory preventative controls for food facilities is the addition of a preventative control plan that includes the following:

1 ) Evaluating the hazards that could affect food safety
2 ) Specifying what preventive steps, or controls, will be put in place to significantly minimize or prevent the hazards
3 ) Specifying how the facility will monitor these controls to ensure they are working
4 ) Maintaining routine records of the monitoring
5 ) Specifying what actions the facility will take to correct problems that arise.

Purchasing and using equipment that meets the Sanitary Design Principles (SDP) falls under these mandatory preventative measures as a control to prevent or minimize the possibility of foodborne contamination and disease. Continue reading →

Benefits of Cardinal Digital Truck Scales

Posted on by

Cardinal Armor series Smartcell digital truck scales have several distinct benefits to you, the customer. First there is the heavy duty weighbridge design the Cardinal Armor digital truck scale uses. For example, the steel deck has (12) 12 inch eye beams across the scale but most important is there’s no moving parts under the scale.

ADVANTAGES OF A DIGITAL TRUCK SCALE

With a traditional truck scale, when it comes to debris build-up under the scale, that you typically see in landfills, quarries, sand and gravel businesses; all of that debris can cause problems under the scale and cause binding. Then you will be forced to have folks out there power washing the truck scale, trying to get the scale to work properly because safe linkage systems or load cells that are mounted to piers; the debris impedes on that critical weighing process.

This can often lead to down time for cleaning and can also lead to your scale being rejected when being tested by the State weights and measures inspector.

Another key element of the Cardinal Armor digital truck scale is simple connections which can also lead to limited downtime. Most important there is no power running to the scale other than the home run cable, that’s very important. Do you know what lightning, rain, and snow can do over time to the junction boxes of a traditional truck scale? There’s over a hundred and eight connection points in many standard analog truck scales.

digital truck scales

But, with the armor digital system, there’s ten. There’s five wires that plug into the terminal connector to go to the first load cell and there’s five that you simply wire into the weight indicator in fact Cardinal chooses 225 and the 825 as indicators of choice but most important for you; you want limited downtime for the life of the truck scale. Continue reading →

I Want To Buy A Scale That Is Made In The United States of America.

Posted on by

The title of this blog post sounds simple enough, right? Many customers are interested in purchasing lots of different items that are made in America versus buying items made in China and other countries. But, I would like to ask you a question…

What exactly do you consider “Made in America”?

The reason I bring this up is that it’s really difficult to find certain types of scales that meet a certain definition.

According to the FTC, for most products there is no law requiring manufacturers and marketers to make a “Made in USA” claim. But if a business chooses to make the claim, the FTC’s Made in USA standard applies. Made in USA means that “all or virtually all” the product has been made in America. That is, all significant parts, processing, and labor that go into the product must be of U.S. origin. Products should not contain any – or should contain only negligible – foreign content. The FTC’s Enforcement Policy Statement and its business guide, Complying with the Made in USA Standard, spell out the details, with examples of situations when domestic origin claims would be accurate and when they would be inappropriate.

For simplicity, let’s look at an industrial floor scale as an example.

Ok so you’re looking to buy an American Made floor scale. Did you know that almost every floor scale that is built in the USA utilizes (4) load cells that were made in China? With that being the case, let’s say your floor scale was built in Rice Lake, Wisconsin but uses load cells from China.  Do you still consider this scale an American Made item?

industrial floor scale

Did you also know that many of the junction boxes and summing boards are made overseas? Finally, did you know that the home run cable, the fifteen foot long cable that connects the scale to your digital weight indicator is probably constructed overseas? And, what about the steel used in the floor scale? Was it purchased domestically?

Sticking with the floor scale example, next area to consider is the digital weight indicator. Is it one hundred percent made in the USA? Were all the boards and components made in America? How about the display board? The plastic or stainless steel enclosure? Was the AC adapter made in the USA?

These are some interesting things to consider. I know of many people who can justify buying a scale that was constructed and calibrated in the USA but does utilize some Chinese components. However, there are some who absolutely want their products to be 100 % made in America.  Are there any scales that can one hundred percent meet that?

From our standpoint as a distributor it can be quite tricky since we are not involved in the actual manufacturing process. We have had numerous scale manufacturers tell us over the years that they build Made in the USA weighing equipment and then over time they slowly start substituting Chinese parts or in some cases, send all the manufacturing over to China. Unless the scale manufacturer tells us, sometimes we are not even aware that anything has changed in the manufacturing process.

So if buying a Made in the USA scale is important to you, contact us and we can help you. Just be sure to specify to us up front how flexible you wish to be when it comes to things like Chinese components such as load cells being a part of the final product.

In our experiences, many customers may originally start a transaction as a “Made in the USA” fanatic but once they discover certain prices and lead times for domestic components, they become a fanatic of “Made in U.S. from Imported Parts” or “Assembled in U.S.A.”.

Installing Load Cells on Suspended Hoppers or Tanks

Posted on by

If you have a hopper or tank in your facility, one great way to accurately keep track of its contents is to weigh it. The ITCM Series modules utilize several Rice Lake Weighing Systems components (mounting hardware, load cells, junction box) to provide an unmatched level of performance in suspended tank and hopper weighing applications and mechanical scale conversions. The ITCM HE incorporates clevis and unique rod-end ball joint assemblies to reduce the overall length to less than half of the traditional tension cell mounts, while providing correct load alignment.

In addition, the load cell is completely electrically isolated from stray currents, which are a major cause of load cell failure. To complete the design, a grounding strap connects the two clevis assemblies to further provide safety to your load cells. As always, the installation should be planned by a qualified structural engineer. Each installation is unique, and this manual is meant to serve only as a general guideline for installation.

The ITCM Weigh Module provides excellent performance in suspended tank and hopper weighing applications. The ITCM reduces the overall assembly length to less than half of traditional tension cell hardware arrangements and offers correct alignment of the assembly. The combination of clevises and rod end ball joints isolates the load cell from extraneous forces detrimental to accurate system performance.

suspended hopper load cell mount for scales

The ITCM incorporates an insulating system which resists the flow of stray currents through the load cell. To insulate the load cells from the clevises, the clevises incorporate nylon insulating washers, and the rod end ball joints are lined with Teflon®. A parallel grounding strap connects the two clevis assemblies to provide an alternate path to ground, preventing load cell damage from electrical spikes or stray currents.

The ITCM modules feature RL20000 series S-beam load cells and are available in a variety of capacities, ranging from 100 to 20,000 pounds per module. A single ITCM module is often used to convert a mechanical scale to electronic operation, allowing for the added benefits of an electronic signal for process control or data collection. When an ITCM module is inserted into the steelyard rod, the mechanical beam or dial is still functional and can serve as a backup indicator.

General Installation Guidelines for Tension Cell Mounts

Depending on the weighing application, ITCM modules may be used in single or multiple load cell configurations. Single cell suspension configurations are relatively simple and work well in low capacity applications which have minimal disturbance from mixers, materials flow, or other agitators.

For best results, the vessel should be symmetrical with respect to the suspension point and used to weigh only self-leveling materials, such as liquids.

This allows the center of gravity to rise along the same vertical line each time and minimizes the tendency of the vessel to bind against the bumpers. The bumpers only serve to limit sway caused by accidental contact or other external forces. Erroneous scale readings result if the vessel contacts the bumper. Instead of bumpers, horizontal stay rods may be used to rigidly hold a vessel which has a tendency to sway sideways. Also, note that single cell systems must be restrained from rotating to prevent the suspension hardware from coming unscrewed.

single load cell tank hopper mount

Multiple cell suspension configurations commonly involve three or four load cells. One advantage to using three suspension points is that even weight distribution is inherent in this configuration. Support points should be equally rigid and deflect by the same amount when loaded. Otherwise, one or more of the cells may be overloaded.

For maximum stability, attach suspension rods at or above the filled vessel’s center of gravity. In situations where there is a potential for vibration, agitation, wind, or seismic activity, install bumpers or horizontal check rods to check the sideways motion of the vessel.

3 and 4 load cell hopper scale mount

We always like to mention that all suspended vessel weighing systems must be protected by safety check rods, chains, or other means to prevent damage or injury in the event of a failure.

If piping or conduit is required, make sure that it runs horizontally and verify that the distance from the vessel to the first pipe support is 20 to 30 times the pipe diameter. If necessary, incorporate flexible sections into the pipe. Suspension rods should be as long as possible to minimize the introduction of side forces.

Use only hermetically sealed load cells in washdown applications. Environmentally protected load cells are not suitable for such applications and will eventually be damaged. If tanks and surrounding equipment are frequently steam cleaned, or if the load cell might be subjected to direct washdown pressure, a protective shroud for the weighing assembly is recommended.

It is important that the S-beam load cells are properly oriented with respect to the load. The cable must emerge from the dead, or fixed, end of the cell. If it emerges from the live end, it will restrain the movement of the cell. This orientation must be followed with low capacity S beams.

correct way to use a s-beam load cell

Installing the ITCM suspended weighing modules

1. Select a suspension rod of the appropriate diameter. Use a safety factor of at least 4, based on the yield strength of the rod material. If vibration or shock loads are common, then a higher factor of safety should be considered. Commercially available threaded rod is made from a low yield strength material and will not provide an adequate safety factor in many applications. When determining the rod length, subtract the length of the ITCM module from the overall suspension length, making allowance for complete thread engagement in each clevis.
2. Making certain to provide adequate thread for the jam nut, cut the suspension rod near its center point and thread the ends that screw into the ITCM module.
3. Making sure to put the jam nut on first, assemble a clevis to the top and bottom rods. Screw the rod in sufficiently so that all threads of the clevis are engaged. Lock each clevis in place using the jam nuts. The clevises should be rotated 90° relative to each other.
4. Initially, the lined rod end ball joints are stiffer than regular rod end ball joints. This is normal. Verify that all threads of the load cell are engaged by the rod end ball joint, then lock in place with the jam nuts provided. Screw the rod end ball joints into the load cell. Align one so the flat face is in the same plane as the load cell. Turn the other to 90°.
5. Insert the rod end ball joint into the upper clevis. Place a nylon washer on each side of the rod end and insert the shoulder screw. Secure the shoulder screw with the lock nut provided. Repeat the procedure on the lower clevis.

Note: The 15K and 20K ITCM models use plain pins secured with washers and cotter pins, rather than threaded shoulder screws and lock nuts.
6. Remove the 1/4” machine screw and lock washer from each clevis. Fasten the bonding strap in place as shown in the illustration below. Make sure to connect the vessel or the support structure to a single system-wide ground.
7. The attachment points on the structure and vessel should be rigid to minimize deflection. Add gusset plates if necessary. Spherical washers help to minimize bending of the suspension rod due to structure or vessel deflection under load. They can also compensate for initial misalignment.
8. In multiple cell applications, adjust the length of each assembly to level the vessel. If the system consists of more than three cells, you must be sure the load is evenly distributed. This may be done by lifting or prying on the vessel at each support point, checking for even load, or by reading the dead load output from each cell. The variation in load among the cells should be no more than 20%.

Load Cell Wiring

1. Route the load cell cables so they will not be damaged or cut. Cables should not be routed near heat sources greater than 150 °F. Do not shorten any load cell cable. The load cell is temperature compensated with the supplied length of cable. Cutting the cable will affect temperature compensation. Coil excess cable and protect it so it will not be mechanically damaged or be sitting in water.
2. Provide a drip loop in all cables so that water or other liquids will not run directly down the cables onto either the load cells or the junction box. Attach load cell cable to the dead structure, not the vessel.
3. If conduit protection is necessary against mechanical or rodent damage to the load cell cables, use flexible conduit and conduit adapters at the load cells.
4. Connect cables for the load cells to the summing board in the junction box according to the load cell calibration certificate provided with the load cell and the labels on the terminal strips of the junction box.
5. For better performance, use positive and negative remote sense lines if the wiring run from the junction box to the indicator is longer than 25 feet.

Junction Box Connections, Adjustments & Calibration

• Refer to junction box manual for trimming details.
• Refer to indicator manual for system calibration details.

Scale Troubleshooting

If the system powers up and gives some type of stable digital readout that varies with the load on the system, the system problems are probably caused by factors other than the load cells. Often, load cells are blamed for a malfunctioning system and the majority of the time, the problem lies elsewhere.

Look for mechanical causes first. If the system can be calibrated but doesn’t return to zero, loses calibration, or demonstrates non-linearity or non-repeatability, see the following chart for possible causes and refer to the following list of checks.

No return to zero
Mechanical binding or debris in seals or under load cells; may have lost system calibration

Non-linearity
Thermal expansion or deflection under load causing binding or side load

Non-repeatability
Loose load cell mount; drifting caused by moisture, load cell overload or shock damage; mechanical binding

Lost calibration
Out of level or plumb; moisture problem; mechanical binding

Drifting readout
Moisture in junction box, cables, or load cell; mechanical binding

1. Check load cell mount for debris restricting load cell movement or debris between scale and structure.
2. Check that tank/vessel and mounts are plumb, level, and square at the critical areas.
3. Check piping and conduit for connections that restrict vessel movement.
4. If check rods are used, loosen connections to finger tight only for testing.
5. Check load cell cables for physical or water damage.
6. Check all electrical connections, especially in the junction box.

Contact the scale sales and service team at Central Carolina Scale today for hopper scale load cells and weigh bars. Nobody stocks more load cells in North Carolina than we do. We can put together a quote for the ideal system for your weighing needs. And when it comes to digital weight indicators, we can meet just about anyone’s requirements for specifications like analog output or a certain price range. We can also repair or calibrate an existing hopper scale. We feature many of the top scale manufacturer product lines to choose from. Call us at 919-776-7737 or complete the Request a Quote form on our website.

Load Cell Repair Service

Posted on by

We can offer you load cell repair services with fast turnaround times and affordable pricing. Our load cell repairs come with a one year warranty and flat rate pricing to help make the repair process easy and worry free.

Our repair service has experience repairing all types of load cells and even offers a load cell Exchange Program. Calibration work and repairs are traceable to the National Institute of Standards and Technology (NIST).

truck scale load cell repair

We offer no hassle load cell repairs with:

  • Fast Turnaround Times
  • Low Repair Rates
  • Long Repair Service Warranties
  • High Temperature Option Available!

Fill out our Request for Quote button on the website and include the manufacturer, model number, capacity, etc… and we can get an estimated quote sent to you.

Load Cell Kit For Weighing Tanks and Vessels

Posted on by

Cardinal Scale Manufacturing has a wide variety of Made in America load cell kits which allow you transform almost any vessel or platform into an integrated weighing system. A few simple things need to be considered when choosing the right system. We’ll also discuss the proper installation and setup methods to use.

Whether utilizing beam, tension, or compression cells in either analog or hydraulic configurations, Cardinal load cell kits give you flexible options to help solve many weighing applications.

To determine the total capacity of the system, you first need to know the total weight of the structure that the load cell stands will be supporting (dead load).

Add the anticipated maximum system live load to the actual dead load, and that total will be the necessary minimum system capacity. Normally, you want to divide this total by the number of load cells and then go up to the next largest size available load cell.

For example, let’s say a tank has an empty weight of 22,000 lb and an anticipated live load of 100,000 lb for a total combined load of 122,000 lb. Using four load cell stands, each cell will be seeing 30,500 pounds of anticipated weight. We would normally use a 50,000 pound load cell in this application. Since many times these systems are under a continual long-term load it is not uncommon for load cells to be almost twice the necessary capacity in order to help reduce signal creep.

load cell kit for weighing tanks

Installation of load cell kits begin by determining if the floor (in the case of stand assemblies) or the building structure (for tension systems) is strong enough to bear the anticipated load. If not, piers or footings may be needed or additional support structures added. For all overhead suspension type systems, safety chains must be provided locally to bear any anticipated load due to component failure.

After the system is assembled, it is necessary to make sure that all of the load cells are taking equal dead load to the extent that it is possible. After the millivolt readings are as close as possible, secure the load cell stand assembles. Grouting the stands in place is the preferred method for long-term accuracy.

Most Cardinal Scale load cell stand kits come with checking designed into the stand itself. Depending on the device, some applications may require additional checking. Mixers and blenders are examples of devices that may need additional checking. Also, very tall tanks or hoppers may require additional restraints due to wind load on the structure.

Many systems using load cell kits require the connection of electrical supply or control wiring, as well as pipes and supply augers. Discharge chutes or pipes are used to get material out of the tank or hopper. It is very important to understand that anything connected to the scale structure must be installed with flexible couplings so that no path is present for force to be shunted off to ground during the weighing process. The more items that are connected to the structure the harder it is to get accurate weights.

For more information, contact the sales team at Central Carolina Scale (919) 776-7737