Aclara SGM1400 Series, User Manual

Page: 36 / 108

26
S G M 1 4 0 0 S e r i e s S m a r t M e t e r U s e r M a n u a l – S M E T S 2
Firmware
Application
The meter firmware application can be upgraded via firmware over-the-air.
Firmware Specifications
The SGM1400-B Series meters have two main processors: the metrology
processor and the application processor.
The metrology processor provides the real-time clock and the measurement and
calculation of energy values. The application processor provides functionality
such as load profile and time-of-use, relay control, communications support, and
Smart Energy Profile.
The meter performs both cyclic redundancy check (CRC) validation and
cryptographic signature validation for the firmware running on the SGM1400-B.
This ensures storage to the meter hardware and that the firmware is an authentic
released image and has not been tampered with in transport.
The SGM1400-B Series meter provides customers with the majority of the above
specified functionality, regardless of whether a communications module is
installed or not. The core of this functionality resides on the metrology and
application processors.
The meter maintains and verifies the checksum of data (such as billing data, load
profile data, TOU data, event log data, etc.) stored in non-volatile memory. The
meter also ensures continuous operation of firmware by means of a watchdog
timer. The meter checks the proper operation of the measurement chip
periodically and takes necessary action to recover from an error condition.
The meter maintains the checksum for calibration and configuration data and
checks its integrity after power returns. During the manufacturing process, Aclara
stores the resultant calibration data for each meter. For MID certification,
calibrated meters were provided to the approved test house for accuracy and other
tests as required.
Metrology Firmware and Data
In accordance with the Guide for Measuring Instruments Directive 2004/22/EC
and WELMEC 7.2, the core metrology firmware and data of the meter are
explicitly isolated from the applications firmware to ensure that the metrology can
in no way be updated or changed.
The meter is designed, constructed, tested, and certified as a European Union MID
approved product. Test reports prepared for submission to, or received from, the
relevant certifying bodies as part of the MID certification process will be made
available to customers upon request.
The meters include the metrology suffix after the CE mark per the requirements
listed in the MID.
Firmware Release Notes Process
Firmware release notes will be provided to the customer. The release note details
are generated from the Aclara software configuration management (SCM) system.