Tension Load Cells

The BSS series is an alloy steel S-beam tension and compression load cell, NTEP Class III certified, rated from 25 to 10,000 lb with ±0.03% nonlinearity, built for hopper scales, tank weighing, and suspended load monitoring in demanding industrial environments.

Tension load cells installed on a suspended hopper weighing system in an industrial environment

TL;DR — Tension Load Cells at a Glance

  • S-beam design for both tension and compression loading
  • 25–10,000 lb capacity across 10 standard models
  • NTEP Class III certified, ±0.03% nonlinearity, ±0.01% repeatability
  • 3.0 mV/V rated output, 390 Ω bridge input impedance
  • 150% safe overload, 300% ultimate overload protection
  • Replaces Rice Lake RL20000, HBM S40, Sensortronics 60001, Celtron STC
  • Alloy steel construction, metric variants available (BSS-KG 200–2000 kg)

At-a-Glance Technical Summary

Capacity Range
25–10,000 lb (11–4,536 kg)
Accuracy (Nonlinearity)
±0.03% of rated output
Rated Output
3.0 mV/V ± 0.05%
Safe / Ultimate Overload
150% / 300% of rated capacity
Material / Seal
Alloy steel, welded construction
Primary Applications
Hopper scales, tank scales, suspended loads
Output Type
mV/V (passive Wheatstone bridge)
Temperature Compensation
-10 to +40°C (14 to 104°F)

What Are Tension Load Cells

An S-beam tension load cell senses force by detecting strain along its vertical axis. Four bonded foil strain gauges arranged in a full Wheatstone bridge configuration measure the material deformation when a load pulls (or pushes) along the cell’s centerline. The BSS accepts both tension and compression, making it versatile for hopper discharge monitoring, tank weight measurement, and suspended equipment weighing.

The S-beam geometry creates two key advantages. First, it tolerates both axial tension and compression without reconfiguring or flipping the cell. Second, the cross-sectional area is large relative to bending beam designs, so S-beam cells carry much higher capacities — 10,000 lb versus the 300 kg maximum of bending beams. The trade-off is a taller form factor. Where vertical space is tight, a single-point or bending beam cell may fit better.

S type load cell showing tension and compression force directions diagram
S-beam load cells measure both tension and compression forces, depending on load direction.

Key Features

Dual-Direction Loading

Single cell handles both tension and compression without adjustment. Hopper discharge pulls the cell downward; tank weight compresses it equally. The bridge output is proportional to force magnitude regardless of direction.

NTEP Class III Certification

The BSS is legally certified for commercial weighing by the National Conference on Weights and Measures. Meets repeatability, accuracy, and overload specs required for trade-approved scales used in commerce.

300% Ultimate Overload

Survives transient loads up to three times rated capacity without permanent damage. A 5,000 lb cell endures 15,000 lb momentary pulses from impact or surge, critical for hopper fill shock and dump impacts.

Multi-Brand Interchangeability

Drop-in replacement for Rice Lake RL20000, HBM S40, Sensortronics 60001, Tedea STC, and Celtron STC. Same mounting eye geometry, cable exit location, and electrical output simplify retrofits.

Series Comparison Table

Series Capacities Accuracy Material Application Price Range
BSS (Flagship) 25–10,000 lb ±0.03% nonlinearity Alloy steel, NTEP Hopper, tank, suspended loads $180–$735
BSA (Economy) General range Standard accuracy Alloy steel General tension/compression $180
BAB-MT 50N–1000N ±0.02% nonlinearity Aluminum, IP67 Small apparatus, research $300
BAB-MT2 Metric/Imperial Ultra high accuracy Premium construction Precision testing, R&D $325–$450
BSS-KG (Metric) 200–2000 kg ±0.03% nonlinearity Alloy steel International markets $275

Who These Load Cells Are For

Hopper Scale Manufacturers & OEMs — Three or four BSS cells suspended beneath a hopper discharge provide repeatable batch weights. The NTEP Class III certification means your finished scale qualifies for legal-for-trade use without secondary certification. Ten standard capacities fit common hopper sizes from 50 lb to 50+ ton systems.
Plant Engineers (Tank & Silo Retrofit) — If your existing tank scale’s load cell is failing, the BSS replaces Rice Lake RL20000 and HBM S40 in the same eye-bolt pattern. Suspend the new cell, run 20 ft of cable to the indicator, and resume production without rework of the tank support structure.
Process Control Integrators — The 3.0 mV/V bridge output and low-impedance design pair directly with industrial transmitters and PLC analog inputs. A Transcell LCT-2 transmitter converts the signal to 4–20 mA or 0–10 V for integration into distributed control systems.
Material Handling Equipment Builders — Suspended load monitoring on overhead cranes, jib arms, and material lifts requires cells that withstand shock loads. The BSS’s 300% ultimate overload rating absorbs drop impacts and swing transients that would damage bending beam or compression cells.
Industrial Automation & System Houses — Multi-cell summing across hopper systems demands matched accuracy and repeatability. The BSS’s ±0.01% repeatability and ±0.02% hysteresis keep cell-to-cell variation below process tolerance when wired through a summing card or digital indicator.

Typical Applications

Hopper Discharge and Batching

Three or four BSS load cells suspend a hopper above a conveyor or packaging line. As material discharges, the decreasing load produces a negative signal proportional to weight lost. Integrating this signal over time yields batch totals. NTEP certification means the system can be used for material billing if coupled with an approved indicator.

Tank and Silo Weighing

Install a BSS cell at each corner of a tank support frame or use 2–3 cells at major load points. The dual tension/compression capability means the cell reads the same magnitude whether the tank pulls upward (tension) or sits on a platform (compression). Stainless or painted alloy steel resists corrosion from spills and washdown.

Tension load cells suspending industrial hopper for batching system with multiple load points
Multiple tension load cells suspend a hopper to measure material discharge in batching systems.

Suspended Load Monitoring

Overhead cranes and jib arms equipped with load cells prevent overload and alert operators. The BSS absorbs the shock of load pickup without permanent deformation. A 1,000 lb cell rated at 1,500 lb momentary can sustain the 3,000 lb transient from dropped packages bouncing on the hook.

Material Handling Scales

Weighing platforms suspended on rope or chain use tension cells to measure the load continuously. Truck scales and goods-in verification scales employ 4–8 BSS cells under a deck. Each cell carries a portion of the total weight, summed through a junction box or digital indicator.

How to Select the Correct Capacity

Begin with the maximum load the cell will support: product weight, vessel dead load, and installation hardware. For tension applications, add the weight of any hanging structure below the cell. For compression, include platform mass. Multiply by a safety factor of 1.5 to 2.0 to accommodate impact, shock, and off-center loading conditions.

Worked example: A hopper weighs 200 lb empty and holds 800 lb of material. Total suspended mass = 1,000 lb. Apply 1.5× safety factor = 1,500 lb. Use three BSS-1000LB cells or four BSS-500LB cells. Three 1,000 lb cells divide the load at 500 lb each, staying well within the linear range. Stepping to BSS-2000LB cells gives more headroom but costs more and is underutilized.

A field mistake seen regularly: oversizing cells to the ultimate overload rating. A 5,000 lb cell rated for 15,000 lb ultimate overload may tempt you to apply 10,000 lb of sustained load. Resist this. Keep operating load at 60–80% of rated capacity to maximize accuracy and service life. Operating at 100% of rated capacity pushes you to the edge of the nonlinearity spec and accelerates creep.

Quick reference: Hoppers 100–500 lb: use BSS-500LB. Hoppers 500–2,000 lb: use BSS-1000LB or BSS-2000LB. Hoppers 2–10 tons: use BSS-5000LB or BSS-10000LB. Distribute across 3–4 cells for even load sharing.

Installation & Mounting Guidelines

S beam load cell mounted in testing machine showing vertical alignment and axial load direction

S-beam load cell aligned vertically in a testing frame, demonstrating proper loading for tension and compression measurement.

The BSS mounts vertically with its upper eye bolted to a fixed structure and the load attached to the lower eye. The centerline of the loading force must align with the cell’s vertical axis. Lateral loads or sideways pull on the cell introduce unwanted bending stress that shifts zero balance and degrades accuracy.

Cable routing is critical. Run the 20 ft four-conductor shielded cable from the cell’s gland downward, avoiding sharp bends that crimp the shield. Where the cable enters the indicator or junction box, coil gently in a 4–6 inch radius to prevent micro-fractures. Pinched cable commonly fails after 6–12 months of thermal cycling and vibration.

A recurring problem in field installations: mounting the cell at an angle or allowing lateral motion. Any sideways movement at the load attachment point creates bending in the S-beam that the strain gauges detect as false weight. A 45-degree angle on a hopper hanging from one cell can shift the reading by 5–10% or more. Always confirm vertical alignment before final tightening.

Technical Specifications Overview

Parameter Value (BSS Series)
Available Capacities 25, 50, 100, 150, 250, 500, 1,000, 2,500, 5,000, 10,000 lb
Rated Output 3.0 mV/V ± 0.05%
Nonlinearity ±0.03% of rated output
Hysteresis ±0.02% of rated output
Repeatability ±0.01% of rated output
Creep (30 min) ±0.02% of applied load
Zero Balance ±1% of rated output
Temp. Effect on Output ±0.0015%/°F
Temp. Effect on Zero ±0.0015%/°F
Compensated Temp. Range -10 to +40°C (14 to 104°F)
Safe Operating Temp. -30 to +80°C (-22 to +176°F)
Safe Overload 150% of rated capacity
Ultimate Overload 300% of rated capacity
Input Impedance 390 ± 10 Ω
Output Impedance 350 ± 3 Ω
Insulation Resistance 5,000 MΩ
Rated Excitation 10 V AC/DC
Maximum Excitation 15 V AC/DC
Material Alloy steel, welded
Cable Length 20 ft, 4-conductor shielded
Loading Direction Tension or compression (vertical axis)

Download BSS Series Datasheet — full dimensional drawings, NTEP certification, wiring diagram, and temperature curves

Standards & Calibration Considerations

Transcell manufactures the BSS under ISO 9001 quality management and NIST-traceable calibration protocols. Every cell is individually tested and certified before shipment. The BSS carries NTEP Class III certification, meaning it meets the accuracy and repeatability criteria set by the National Conference on Weights and Measures and can be deployed in commercial weighing systems subject to legal-for-trade regulation.

NIST traceability certifies that the test weights and reference standards used during factory calibration connect to the National Institute of Standards and Technology through an unbroken chain of comparison. For applications requiring compliance with ISO 9001, FDA 21 CFR Part 11, GMP, or SQF standards, this documentation is essential. Transcell includes the NIST-traceable calibration report at no additional charge.

For systems requiring OIML R60 legal-for-trade approval (meat, dairy, grain facilities), confirm that your complete system — cell plus indicator — meets the accuracy class needed in your jurisdiction. The BSS specifications support Class C3 performance, but system certification depends on indicator selection, installation quality, and local regulatory authority approval.

How Transcell Compares

The BSS is in stock at the Transcell Illinois warehouse. Standard capacities ship within 2–5 business days. Sourcing equivalent NTEP cells from overseas manufacturers typically requires 6–12 weeks, adding cost and delay to hopper retrofit projects and OEM schedules.

Pricing sits between imported European cells and ultra-budget commodity models. The BSS offers NTEP Class III certification, full technical support, and NIST-traceable calibration as standard features without upcharge. Competitors often sell the cell at a lower headline price but bill separately for calibration ($200–400), documentation ($50–100), and technical support.

Transcell’s application engineering team responds within 24 business hours to capacity selection, mounting review, and cross-reference questions. A plant engineer retrofitting a tank scale can email a photo of the existing cell and mounting, and Transcell will confirm whether the BSS is a drop-in replacement, or suggest a different model. This level of support keeps retrofit projects on schedule.

Get a Quote for BSS Tension Load Cells

Tell us your capacity, quantity, and application (hopper, tank, suspended load). Our engineering team will confirm compatibility and deliver pricing within 24 business hours.

Request a Quote →

Related Products & System Components

Frequently Asked Questions

Can the BSS be used for both tension and compression?
Yes. The S-beam geometry and full Wheatstone bridge configuration measure force in both directions. A hopper pulling downward on the cell produces the same output magnitude as material stacked on top. There is no need to flip or reconfigure the cell for compression applications.
What’s the difference between NTEP Class III and legal-for-trade?
NTEP (National Type Evaluation Program) Class III is a U.S. certification indicating the load cell meets specific accuracy and overload standards set by the National Conference on Weights and Measures. A complete scale system (cell plus indicator) carrying NTEP approval can be used for commercial weighing where the weight is legally binding (e.g., selling grain by weight). The BSS holds NTEP Class III; your indicator must also be NTEP certified for the system to qualify.
Can I use a BSS as a drop-in replacement for my Rice Lake RL20000?
In most cases, yes. The mounting eye-bolt pattern, cable exit location, and rated output (3.0 mV/V) match the RL20000. Confirm the capacity matches, then swap the cell and recalibrate your indicator. Provide your current RL20000 capacity when requesting a quote so Transcell engineering can verify dimensional compatibility for your specific installation.
How do I know if I need 3 or 4 cells under my hopper?
Divide the total hopper load by the number of cells to determine load per cell. For even load distribution and redundancy, use 4 cells — one at each corner of a rectangular hopper frame, or symmetrically spaced under a round hopper. Three cells work if the hopper geometry ensures equal load sharing. Transcell engineering can review your hopper structure and recommend the optimal cell count and capacity for your specific design.

Application Engineering Support

Need help selecting the correct BSS capacity for your hopper, tank, or suspended load application?

Our engineering team responds within 24 business hours. Capacity selection, mounting review, cross-reference verification, and system integration support included.

Transcell Technology Inc. · Buffalo Grove, IL · Since 1981

+1-800-503-9180
sales@transcell.com