Axle Load Sensor | Products

Overview

SGT Axle Load Sensor is a strain-gauge and air-bag pressure sensing kit for trucks, trailers and tippers that measures weight-on-wheel for every axle in real time and computes Gross Vehicle Weight (GVW) on the move. It replaces the once-a-day weighbridge ritual with continuous, audit-grade load data the driver sees before pulling away.

Overloading is the leading cause of premature chassis fatigue, brake failure and regulator fines in commercial transport. With sensors clamped to leaf springs or tapped into the suspension air-bag line, the system reads load every second, computes per-axle and total weights, flashes a cab warning before the truck moves, and writes a tamper-evident weigh-ticket to the cloud.

Per-axle weight — strain-gauge or air-bag pressure on every axle
GVW total + per-axle limits — fleet-specific policy, per-vehicle calibration
Overload alarm in-cab — flashes before the driver releases the parking brake
Weighbridge-free — audit-grade tickets stored in the cloud, no detour to a public scale

How It Works

Truck + Axles — strain-gauge transducers clamp to the leaf spring or pressure-tap into the air-bag line of each axle. Sensors are powered from the chassis 24 V bus and report over CAN-bus or RS-485 to the gateway.
Weight Calculation — the gateway reads the Wheatstone-bridge millivolt signal, applies the per-vehicle calibration curve, temperature-compensates, and produces axle weights with ±2% accuracy. GVW is the sum.
Compliance Cloud — every event (loading, departure, overload) writes a tamper-evident weigh-ticket with timestamp, GPS, photo (optional), per-axle weights and signature. Regulator-ready reports are exported on demand.
Driver / Loader — the driver sees a live load gauge in the cab; the warehouse loader sees the same data on a phone or yard display so they stop adding cargo before the limit is breached.

Features

Strain-gauge or air-bag — choose per axle: strain on leaf-spring rigid axles, air-bag pressure on air-suspension axles
±2% accuracy — comparable to a static weighbridge after one-time calibration
Temperature compensation — automatic correction for hot brakes / cold mornings, ±0.05%/°C drift
In-cab display — color LCD with per-axle bars, GVW gauge, and overload buzzer
Tamper-evident tickets — every weigh-event signed with device key, written to immutable cloud log
Photo capture — optional yard-camera trigger on load-complete for proof of contents
Loader app — yard-staff app shows live weight while loading, prevents accidental overload
API + ERP integration — REST and webhook to your TMS / ERP so dispatch knows the load is legal before it leaves

Use Cases

Bulk haulage — aggregates, cement, grain, where loading is by shovel and overload risk is highest
Container drayage — confirming the manifest weight matches the actual axle distribution
Logging / timber — variable density loads, no weighbridge near forest sites
Tipper / construction — site-to-site moves where weighbridge access is impossible
Regulator-mandated fleets — jurisdictions requiring on-board mass monitoring for B-double / road-train classes
Self-billing & toll roads — automated GVW-based road-toll declaration

Specifications

Sensor type: bonded foil strain-gauge (350 Ω full bridge) or 0–10 bar air-bag pressure transducer
Range: 0–15 t per axle (configurable), 0–80 t GVW
Accuracy: ±2% of full-scale after calibration, drift < 0.5%/yr
Sampling: 100 Hz raw, 1 Hz reported, event-driven peak hold
Gateway: 24 V automotive, CAN-bus, RS-485, 4G LTE, GNSS
Cab display: 4.3" color LCD, sunlight-readable, IP54, with buzzer
Environmental: sensors IP69K, gateway IP54, −40 to +85 °C operating
Certifications: E-mark, OIML R134 (legal-for-trade option), FCC, CE, RoHS