Download Software Guide (Measuring Instruments Directive 2004

WELMEC WG7
Software Guide
Risk Class B
Risk Class C
WELMEC 7.2, Issue 5
Risk Class D
I3-6: Imprinted Software Identification
The software identification is usually presented on a display. As an exception for active electrical
energy meters, an imprint of the software identification on the name plate of an instrument shall be
an acceptable solution if the following conditions A, B and C are fulfilled:
A. The user interface does not have any control capability to activate the indication of the
software identification on the display or the display does not allow technically showing the
identification of the software (mechanical counter).
B. The instrument does not have any interface to communicate the software identification.
C. After production of a meter a change of the software is not possible or only possible if also the
hardware or a hardware part is changed.
Specifying notes:

The manufacturer of the hardware or the concerned hardware component is responsible that the
software identification is correctly marked on the concerned hardware.

All other Specifying Notes of P2/U2 apply.
Required Documentation:

According to P2/U2.
Validation Guidance:
Checks based on documentation:

According to P2/U2.
Functional checks:
According to P2/U2.

Example of an acceptable solution:
Imprint of the software identification on the name plate of the instrument.
10.3.4 Examples of legally relevant parameters
Electronic utility meters often have a lot of parameters. They are used as constants
for calculations, as configuration parameters etc but also for setting up the
functionality of the device. Concerning identification and protection of parameters and
parameter sets refer to requirement P2 and P7, guide P.
In the following some typical parameters of active electrical energy meters are given.
(This table will be updated when WELMEC Working Group 11 has decided on the
final contents.)
Parameter
Protected
Calibration factor
x
Linearisation factor
x
Settable Comment
10.3.5 Other aspects
For domestic applications it is expected that download of software (extension D,
Chapter 9) will not be very important.
The cumulating energy or volume register of domestic instruments is not a long-term
storage in the sense of extension L (Chapter 6). For an instrument that only
80