MID – Measuring Instruments Directive

What does MID stand for?

This refers to the measuring instruments directive 2004/22/EC of the European parliament and the council dated the 31st March 2004

General Purpose for MID approval?

The purpose of the directive is to create a single market in measuring instruments for the benefit of manufacturers and consumers across Europe. Approval to MID is required for meters used in any billing application. National rules that deviate from MID are not permitted. With the MID European Type Approval Certificate an instrument may be widely sold and used in any European Union (EU) or European Economic Area (EEA) member state. 

- For electricity meters the instrument-specific annex is: MI-003 (active electrical energy meters)

EN50470-1/3 Standards for Accuracy

The EN50470-1/-3 standard defines three specific accuracy classes: A, B and C. These are comparable to the IEC62053-21/-22 active energy metering standard: Class A is equivalent to 2% accuracy, Class B to 1 % and Class C to 0.5 %.

What is Assessment B+D?

The meter has been granted design approval by a notified body to Annex B. The manufacturer calibrates, seals, and self-certifies the meters; the process is approved to EN29002. Meters produced under these conditions conform to the Annex B + Annex D approval.

What are the aims of the MID?

• EU-wide regulation of the market access of respective measuring devices
• Creation of a harmonised standard European market for measuring devices
• Uniform approval process for all EU states and individual additional states - Single, uniform approval testing
• Uniform, cross-border specification for first calibration
• Uniform product labelling
• Reduction of tests and test costs
• First calibration takes place through a manufacturer's declaration of conformity
• Separate calibration testing and calibration fees omitted
• Reduced delivery times
• Equality in competition due to high requirements for product quality
• Additional requirements regarding precision in the small load range - Higher EMC requirements
• Improved picture of the latest measuring technology stats

Replacing meters and legislation surrounding your billing meter

All meters approved by UK legislation can be used up until their certification life. Any replacement meters however, must be MID approved as of October 2016.Tenants can refuse to accept any bill  received based on non certified meters from this date.

Landlord Obligations

Landlords, estate managers and property developers should ensure that they have legally viable fitted throughout their premises. The use of unapproved meters for billing could result prosecution. A tenant is within his/her's rights to refuse payment if the electricity bill has been accumulated from a non-approved meter.