Weighbridge verification: test weights now 20%.

Short answer: a Press Information Bureau release of 6 July 2026 announced that the Department of Consumer Affairs has amended the Legal Metrology (General) Rules, 2011 for weighing instruments of one tonne and above, which includes every weighbridge. Earlier, the inspector had to use standard (test) weights of at least one tonne or 50% of the weighbridge’s maximum capacity, whichever was greater, before substituting them with other loads. Now, once the weighbridge passes a repeatability test, standard weights of one-fifth (20%) of maximum capacity are enough. For a 60 MT weighbridge that means 12 t of standard weights instead of 30 t. The release does not give an effective date, so confirm with your State department before the visit.

The change was announced in a Press Information Bureau release dated 6 July 2026. This guide explains what changed, how the verification test works, and what a weighbridge owner should do before the next stamping. It is a plain-language summary, not legal advice: the inspector of your State’s Legal Metrology department carries out the test and decides the procedure on the day.

What the July 2026 amendment changed

• Which instrumentsWeighing instruments with a maximum capacity of one tonne and above. Every truck weighbridge falls in this group.
• The old ruleStandard weights of at least one tonne or 50% of the maximum capacity, whichever was greater, had to be used before the rest of the test load could be built up by substitution.
• The new ruleIf the weighbridge passes a repeatability test, the standard weights needed before substitution come down to one-fifth (20%) of the maximum capacity.
• Accuracy stays the sameThe release says the prescribed standards of verification accuracy and reliability are kept. Only the mandatory quantity of standard weights required before substitution with constant loads changes.
• WhyThe repeatability test shows the weighbridge gives consistent, stable readings, which allows reliable verification with fewer standard weights. The release says the change is based on internationally accepted metrological principles.

Standard weights needed: old vs new

The figures are simple percentages of maximum capacity, for illustration. For a weighbridge, 50% of capacity was always more than one tonne, so the 50% figure was the one that applied. The quantity actually brought to your site is set by the Legal Metrology department and the test plan for your weighbridge.

How a weighbridge is tested: substitution in plain words

No department can bring 60 or 100 tonnes of certified weights to every weighbridge. So the test load is built up in steps, which is what “substitution with constant loads” means:

• 1. Standard weights firstCertified standard weights are placed on the weighbridge and the reading is checked against their known value.
• 2. SubstituteThe standard weights are taken off and replaced with another stable load that gives the same reading.
• 3. Add the standard weights againThe standard weights go back on top of that load, so the test load rises in steps, and the reading is checked at each step up towards maximum capacity.
• Where the repeatability test fitsIn a repeatability test the same load is weighed more than once and the readings must agree within the permitted limits. Under the 2026 amendment, a successful repeatability test is the condition for using the smaller 20% quantity of standard weights before substitution.

This is a general description; the order of tests, the loads used and the limits are set by the rules and applied by the inspector. If the weighbridge fails the repeatability test, the reduced quantity cannot be used, so the weighbridge must be in good order before the visit.

What it means for weighbridge owners

Get your weighbridge ready to pass the repeatability test

The smaller quantity of standard weights depends on a successful repeatability test. A weighbridge that drifts, sticks or reads differently each time will fail it. Before the inspector’s visit:

• Clear the gapsNothing may touch the weighbridge except the load cells: no stones, mud or debris between the platform and the foundation or ramps.
• Dry load cells and junction boxDrain the pockets or pit, check the cables, and keep the junction box closed, sealed and dry.
• Check zero and a known truckThe empty weighbridge must return to zero. Weigh one known truck a few times and note whether the readings agree.
• Calibrate before the visitWe calibrate the weighbridge before the inspector arrives and support the stamping. Daily and monthly checks are in the maintenance checklist.
• Keep the papers readyPrevious verification certificate for re-verification, and the documents your State department asks for.
• Know your due dateUse the stamping due-date tool to see when the 12 months run out, and plan the test before that date.

Built to verify cleanly

Symphony weighbridges are built to OIML R76 Class III with IP67/IP68 load cells and SMFW weighing software. Symphony holds the Legal Metrology model approval certificate and manufacturer licence for its weighbridges. We build 10–100 MT weighbridges from 7 to 18 m in pit-less, pit-type, concrete (RCC) and modular designs, with free civil consultation and installation. A reminder-based AMC tells you before the 12 months run out. To choose the right size, see choosing capacity and size. We serve plants in Ahmedabad, across Gujarat and all over India.

वेटब्रिज सत्यापन 2026: मानक बाट अब क्षमता का 20%

Book calibration before your verification Free weighbridge tools