AST-221

S Type Load Cell

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AST-221

S Type Load Cell

ADI CONTROLS Model AST-221 is a S-type load cell (also known as an S-beam or S-shaped load cell) is a tension and compression force transducer characterized by its distinct S-shape. It’s highly versatile, designed to measure both tensile force (pulling) and compressive force (pushing). This dual-capability is one of its primary advantages. When a force is applied (either tension or compression), the S-shaped body deforms slightly. Strain gauges bonded to the internal webs of the S-shape measure this deformation and convert it into a proportional electrical signal. It is also known as 20210

Product Type

Single Point Aluminium Load Cell

Usage

Table top scales, Counting and postal scales, Check weighers.

Material

Aluminium

Output

 Analog Sensor

Theory

Resistance Sensor

Compensated Temperature

10 To 60 Celsius (oC)

Rated capacity (Kgf)

20, 50, 100, 200, 250, 300, 500, 750
1, 1.5, 2, 2.5, 3, 5,7.5,10

Excitation Voltage

10VDC-Maximum 15 VDC

Rated Output

3.0 mV/V

Non – Linearity

< ± 0.025 % FSO (Full scale Output)

Hysteresis

< ± 0.02 % FSO

Non-Repeatability

< ± 0.01 % FSO

Creep error (30 minutes)

< ± 0.03 % FSO

Zero Load Output

± 1.0 % FSO

Input Resistance

390 ± 15 Ohms

Output Resistance

350 ± 5 Ohms

Insulation Resistance

>1000 Mega Ohms

Safe Overload

150 % of Rated Capacity

Ultimate Overload

250 % of Rated Capacity

Temperature
Compensated Range

0 to 60° C

Temperature Effect on
Output

<0.0015 % FSO/° C

Temperature Effect on
Zero

< 0.002 % FSO/° C

Side Load Allowed

50 % of Rated Capacity

Deflection

< 0.5 mm at FSO

Finish & Construction

Electroless Nickel Plated Tool Steel

Environment Protection

IP 67

Tightening Torque

Refer Table

Industries

Batching & Mixing Plant
Silo Weighing
Hopper Weighing
UTM MACHINES
Robotics
Packaging Machines
SUSPENDED HOPPER
Tank Weighing
Conveyor Belt Scale

Related Products

FAQs

frequently asked questions

01. What is an S-Type Load Cell and what is its main advantage?

An S-Type load cell, often called an S-Beam load cell, is a force transducer named for its distinct “S” shape. Its unique mechanical design allows it to accurately measure force in two directions:

  • > Tension (Pulling Force): Commonly used in suspended weighing applications like crane scales, hopper scales, and tension test rigs.
  • > Compression (Pushing Force): Used in bench scales, material testing machines, and tank weighing systems.

The main advantage is its versatility and compact size, which makes it ideal for inline force measurement where space is limited and both pushing and pulling forces need to be monitored.

02. What are the most common applications for S-Type load cells?

What are the most common applications for S-Type load cells?

S-Type load cells are preferred in systems requiring high accuracy for both tension and compression measurements.

  • > Tank and Hopper Weighing: Used in a suspended configuration for measuring the contents of large vessels.
  • > Material Testing Machines: Integral to tensile and compression testing equipment to determine the strength and durability of materials.
  • > Suspended Weighing: Hanging scales, crane scales, and lifting mechanism monitoring.
  • > Batching and Packaging Systems: Used for precise fill control and weight checks in production lines.
  • > Tension Control: Monitoring cable, web, or belt tension in manufacturing processes.
03. How do I properly install an S-Type load cell for accurate readings?

Accurate installation is critical, as S-Type cells are sensitive to off-axis (side) loading.

  1. Axial Alignment: The applied force must be perfectly aligned with the central axis of the load cell (the vertical line passing through the two threaded holes).
  2. Use Accessories: Always use appropriate mounting hardware like rod end bearings (clevises or eye bolts) on both the top and bottom mounting holes. These accessories help ensure the load remains axial and compensate for minor initial misalignment, preventing inaccurate readings and potential damage from bending moments.
  3. No Bending/Torsion: The setup must prevent any side forces, bending, or twisting (torsional) moments from reaching the load cell body.
04. How do I select the correct capacity (Rated Load) for my S-Type application?

The rated capacity should always be higher than the maximum expected force to ensure safety and prevent overload damage.

  • > Static Load: For a purely static (non-moving) application, select a load cell with a capacity of 120% to 150% of the maximum expected load.
  • > Dynamic/Shock Load: For applications involving sudden movements, vibration, or shock loading (like crane or packaging systems), select a capacity of 150% to 200% of the maximum expected load.

Always account for the weight of any attached rigging (like eyebolts or cables) when calculating the total maximum load.

05. What are the typical materials and IP ratings available for S-Type load cells?

S-Type load cells are commonly manufactured from materials suitable for industrial use:

Material

Typical Application Environment

IP Rating

Alloy Steel

General industrial use, high strength, cost-effective.

Usually IP65 (Dust-tight, protected against water jets).

Stainless Steel

Harsh, corrosive, or wet environments (e.g., food & beverage, chemical processing).

Usually IP67 (Waterproof immersion up to 1m) or IP68 (Continuous submersion).

The IP (Ingress Protection) rating is key. For most indoor, dry environments, IP65 is sufficient. If the load cell will be exposed to regular washdowns, high humidity, or outdoor weather, an IP67 or IP68 rating is essential for longevity.