TS–014 Secondary indicators on weighing instruments

This policy defines the use of a secondary indicator when used in addition to an approved primary indicator.

Reference documents


Secondary displays are not covered under Certificates of Approval unless they have been tested against OIML R76, therefore unless it is part of or has been issued with a Certificates of Approval, it may not be stamped with the Mark of Verification.

Trading Standards prescribe the following conditions to be met when a secondary indicator is fitted to an approved weighing instrument:

  • The secondary display may only be used in addition to the primary indicator, and
  • Any secondary display must be in the same display configuration and duplicate the value of the primary indicator, and
  • Any printed information must be generated by the primary indicator.

In addition, when carrying out a verification or inspection test, the weighing results from the secondary indicators and printers must be checked in conjunction with the primary indicator. The maximum permissible errors applicable to secondary indicators/printed results are same as that applied for the weighing instrument to which the device is connected.

It must be documented on the test sheet that the secondary indicator is operating in accordance with this policy.

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This policy is to be read in conjunction with any conditions specified in the Certificate of Approval for that instrument.

There are no set requirements in regards to what properties (enunciators) of the primary indicator a secondary indicator must have and there is no obligation for the secondary indicator to replicate all the properties of the primary indicator (e.g. zero indication, in motion indication, net or gross indication etc).

However, if any of these properties are displayed on the secondary indicator, then they must replicate the primary indicator in function and reading. If any of these functions do not operate correctly, they must be repaired or that particular function disconnected.

Trade Measurement — Technical Policy

Policy number: TS - 014
Effective date: July 2016
Version date: October 2016
Version number: 2
Policy name: Secondary indicators on weighing instruments
Reviewed by: Davis White, Legal Metrology Advisor and Senior Trading Standards Officer
Approved by: Phil Sorrell, Team Leader Compliance and Inspection