Load cell types: there are several load cell designs common in the industrial load cell market. This article will cover with the most common types and common uses for these types of load cells. The various designs all have their unique advantages an disadvantages, We always recommend discussing your needs with an experienced load cell sales technician before making a purchase.
The S-type or S-beam load cell is designed to be be used in tension and compression. Typical non-linearity specification of 0.025% of full scale (when used in tension), most manufacturers don’t list the accuracy in compression sometimes being 2-3x worse than the rated specification.
Capacities range from 0.5 lbs for the miniature s-type load cell ranging up to 20,000 lbs for the standard models.
- General tension measurement
- Tensile testing machines
- Tension vessel weighing scales
- Mechanical truck scale conversions
- Below the hook weighing for cranes and hoists
The beam load cell is used in compression weighing scales. Very accurate design with a typical non-linearity of 0.025% of full scale. Manufactured from alloy and stainless steel with various degrees of sealing from potting to welded hermetic seals. The single ended beam load cell is mounted as a cantilever, rigid on one end the and load is applied to the opposite end. Double ended beam load cells are mounted one either end and loaded in the center. Capacities range from 10 grams to over 100,000 pounds.
- Barrel & floor scales
- Vessel weighing
- Truck scales
Single point load cells are moment compensated, simply meaning you can mount a platform up to the maximum size listed on the specification sheet and place the weight anywhere on the platter and achieve an accurate reading. Mainly manufactured from aluminum and stainless steel but a couple manufacturers build them from alloy steel as well. Capacities range from 300 grams to around 1,000 kg.
- Platform scales
- Counting scales
- Bag / container filling scales
In general miniature load cells are built as small as possible for limited space applications. Nearly every type of load cell has a miniature equivalent. The down side to making these force transducers so small is you give up accuracy, for size. Miniature button load cells for example range from 0.25% to 0.5% non-linearity, where a larger canister load cell of the same capacity could be 10x more accurate.
- Limited space applications
- Press force measurement
- Medical applications
Donut / Thru-Hole Load Cells:
The load cell calibration technician’s nemesis, the thru-hole or washer type load cell. This type of load cell is very sensitive to uneven loading situations, we recommend using a set of spherical washers to help distribute and align the load. Built to measure forces that have to pass through the load cell. Typically manufactured from stainless steel. These load cells are rated anywhere from 0.25% to 1% non-linearity. Real world accuracy is probably more like 3-5%. Although some applications do not require high accuracy so this sensor may still be a solution.
- Bolt / Fastener testing
- Anchor testing
- Structural testing
The canister load cell, sometimes referred to as a column load cell is larger than some other types of the same capacity but is typically more accurate. Most commonly manufactured from 17-4 stainless steel, and sealed for industrial environments. Both tension and compression canister load cells are available. Capacities typically range from 10,000 to over 2,000,000 pounds.
- Railroad scales
- High capacity vessel weighing
- Testing machines
- Press calibrations
Tension links are designed to have a shackle installed on either end of the load cell, tension measurement only. The inexpensive models have the eyes oriented in the same direction which is suitable for well controlled inline tension. If the load might sway the more expensive models that have the eyes turned 90 degrees from one another allows one more axis of movement. Typical load cell accuracy is 0.05%, capacities for the tension link can range from 1,000 to 500,000 pounds or higher.
- Mooring testing
- Winch load monitoring
- Subsea salvage recovery
- Dredging operations
- Crane scales