Understanding Load Cell Overload

Load Cell Overload

When you're talking about load cells in process weighing, what does safe and ultimate overload mean, and how strong are load cells?


The ultimate strength relates to the function as a load cell and not the mechanical strength. The mechanical strength of the load cell is even higher. 


For a load cell, there is generally three capacity limits:  


The nominal capacity of one 100%: Let's say we have a 100-pound load cell. This is the limit or capacity of the load cell. Note the load cell should not be subjected to higher forces under regular use. If the application needs to measure higher loads, then a larger load cell should be used.


The safe load usually is 200 percent of the rated capacity: Let's say with the 100-pound load cell this would be 200 pounds. If the load cell is occasionally subjected to more than 100 percent but less than 200 percent, nothing happens to it, and it will work. If repeatedly subjected to more than 100%, the load cell can be damaged due to fatigue.


The ultimate load is usually 300 percent of rated capacity or 300 pounds for a 100-pound load cell. If the load cell is occasionally subjected to a load greater than 200 percent but less than 300 percent, the load cell will be subjected to a zero shift. However, in most cases, the load cell can be recalibrated and repaired. If subjected to more than 300 percent, the bonding of the strain gauges will most likely be damaged beyond repair. The function of the load cell is damaged, and it should be scrapped. 


As a reminder, this refers to the function as a load cell and not the mechanical part. The mechanical strength of a load cell varies but is often in the range of 400 to 1 000 percent. It should also be noted that there's a fatigue limit for a load cell that generally is 133 of capacity. 



Choose Druck for Supply Chain Confidence

Choose Druck for Supply Chain Confidence

Since the pandemic, supply chain disruptions have posed a significant threat to the global economy. Factory closures and lockdowns in China and several other nations, labor shortages, strong demand for commodities, logistics network disruptions, and capacity limits have resulted in significant delivery times. Manufacturers have had to make tough choices, even relinquishing agency approvals on whole product lines.

Druck maintains regular lead times on pressure instruments and has shortened lead times from 4 weeks down to 3 to meet manufacturers' demands, particularly those facing supply chain disruptions. 

According to a poll done by the National Association of Manufacturers, 36% of companies suffer supply chain disruptions, with items arriving late or not at all. Druck works closely with its supply chain to maintain a 3-4 week delivery on the UNIK 5000 series. 

As firms look for alternative suppliers, Druck demonstrates their dependability as a domestic pressure instrument supplier, serving critical industries.

For more information about Druck products in New England, contact AP Corp.
(508) 351-6200

The Druck PACE CM3 Pressure Controller


AP Corp presents the Druck PACE CM3, a new custom-built system where the fastest pressure controller, PACE, and Druck's most accurate reference control module, CM3, are combined into one powerful, high-precision pressure measurement and control solution. PACE CM3 is part of a new generation of high precision pressure controllers from Druck. Using TERPS technology at the core, delivers an unprecedented level of performance and accuracy.

For more information about Druck products in New England, contact AP Corp.
(508) 351-6200

Sensuron - Distributed Measurement Using Fiber Optic Sensing

Distributed Measurement Using Fiber Optic Sensing

Sensuron provides intrinsic fiber optic sensing technology, using the fiber optic cable as the sensor. There are three generations of intrinsic fiber optic sensors: point fiber bragg grating (FBG) based sensors, scattering based sensors, and spatially continuous FBG based sensors. Scattering techniques use fully distributed measurements, whereas FBG techniques can use a small number of sensing points or be fully distributed, depending on how the system interprets the signal from the sensing element. 

FBGs, manufactured into the fiber's core, act like tiny mirrors. Each grating reflects a portion of the signal to the system as light travels down the fiber. The system detects and interprets changes in the returning signal to provide accurate strain and temperature measurements. The majority of FBG-based systems have a few sensing points along each fiber. While this multiplexing capability improves legacy technology, it still does not provide the sensor density required for monitoring continuous distributions. Precision, dynamic testing, and high-speed data acquisition are advantages of point FBG sensors. 

Scattering techniques do not use FBGs at all instead of relying on flaws in the fiber optic cable to obtain readings. There are three types of scattering technologies used in sensing systems today, each with its own set of capabilities. In general, distributed data and long sensing lengths benefit scattering-based fiber optic sensing systems. They are, however, limited to static operation due to low data fidelity, prolonged data acquisition rates on the order of minutes, and susceptibility to vibration. 

Sensuron employs a method that combines the advantages of point FBG sensors and scattering-based systems. Sensuron uses FBGs as the sensing element in their fiber but inscribes them continuously along its length. This process, including the signal interpretation technique, enables their platforms to collect spatially continuous data while maintaining the precision, dynamic testing, and high acquisition rates provided by FBGs. Engineers benefit from accurate measurements of full strain fields, temperature gradients, and other parameters in both static and dynamic environments. Sensuron's platforms can also measure internal and applied loads, deflection, 3D shape, and liquid level using the distributed strain data provided by the fiber.

For more information about Sensuron in New England and Upstate New York contact AP Corp. Call (508) 351-6200 or visit https://a-pcorp.com.

The Dynisco LMI5500 Series Melt Flow Indexer

Dynisco LMI5500

Of all the tests used by the plastics industry, melt flow rate testing (or melt flow index) is the most widely used. It is traditionally associated with testing polyethylene materials to determine the lot-to-lot consistency of resin lots or batches for quality control purposes. It is, however, also used for other purposes such as testing new materials, determination of material stability versus residence time within plastics processing equipment, or the assessment of regrind content within materials or moldings. It is generally a low shear rate test; however, larger weights can increase the shear rate.

A flow rate test measures a polymer’s mass flow rate (grams extruded in 10 minutes) using an orifice under specified conditions of temperature and load. Machines that determine flow rate are generally called Melt Indexers or Extrusion Plastometers. Test methods by ISO, DIN, ASTM, and others specify heat chamber and piston tip diameter such that the shear stress on the polymer is the same in all machines for a given load. In addition, material specification guidelines (by ISO, DIN, ASTM, GM, etc.) may exist, providing further constraints on how a particular material processes.

Specifically designed for the thermoplastics resin industry, the Dynisco LMI5500 Series Melt Flow Indexer has an array of features and benefits that range from ground-breaking accuracy to a unified software platform between all laboratory and online production equipment.

(508) 351-6200

Summary of Features for Ambrell's EKOHEAT® with VPA Technology™

EKOHEAT with VPA Technology

The EKOHEAT product family integrates Ambrell’s exclusive Versatile Performance Architecture (VPA). This technology breakthrough in design architecture, which includes an all-new innovative feature set, provides more versatility than any other induction heating system available today — all while delivering exceptional product performance.

Auto-Scan Capability
While an Ambrell Applications Laboratory will test your application and determine the necessary frequency, you may decide to take on additional applications later. If so, Auto-Scan will scan your application, auto-set the starting frequency and recommend RF setup parameters. If your application is outside of your EKOHEAT VPA model’s capabilities it will even offer recommendations.

High Resolution RF Output
The EKOHEAT VPA displayed RF output is the power actually delivered to the workhead. Resolution is better than 0.05% of full scale.

Universal Printed Circuit Boards
Regardless of system size and frequency, all EKOHEAT VPA products use common printed circuit boards (PCBs). A single board set addresses multiple EKOHEAT VPA systems, minimizing your inventory and eliminating model specific versions.

Industrial Ethernet Communication Compatibility
Industrial and Automation environment networking is fully supported using our chosen gateway that include CIPs (Common Industrial Protocols) such as EthernetIP, Modbus/TCP, and PROFINET protocols.

Easy-to-Use Touch Panel
The front touch panel display will allow you to easily adjust key operating parameters, change languages and read system diagnostics.

Soft Start Circuitry
AC power will not be disrupted when switching on the power to your EKOHEAT VPA power supply thanks to this feature. It eliminates the risk of tripping up other equipment when a power supply is turned on.

Universal Application Setup
The EKOHEAT VPA RF transformer accommodates worldwide voltages and provides the same output voltage. An application conducted in Europe uses the same application setup in the United States.

Two Remote Inputs
Added versatility is provided using a second remote input. Additional process variables, such as temperature can be measured, displayed, recorded and played back with the associated generator parameters.

Application Record and Playback
This feature enables you to record your heat cycle – for up to five weeks – and play it back. The benefit is that you can optimize your application and run it in the most efficient manner.

Ability to Add Power
All EKOHEAT VPA systems have the ability to work together. If you install a 250 kW system and realize later that you need 375 kW, just add a 125 kW system and they will work together seamlessly to deliver 375 KW.

RoHs Compliant
EKOHEAT VPA systems are RoHs compliant, meaning they are free of hazardous materials.

For more information about Ambrell products in New England, contact AP Corp. Call (508) 351-6200 or visit https://a-pcorp.com.