Functionality
The CU will eventually be available in 4 form factors:
Plug into common base socket, PLC Comm’s & internal Relay as a first option;
Wall mount and plug into mains socket, PLC Comm’s & battery backup.
These CU’s will follow:
Plug into common base socket, PLC Comm’s & Battery Backup;
Wall mount, hard wired to Meter.
Installation
The meter is designed to comply with standard meter box types.
Form factor is DIN Rail mount for the meter and the consumer unit available in either common base interface or plug into mains socket and wall mount, hard wired.
Consideration has been given to the method of linking the CU to the Meter, with an emphasis on ease of installation. A menu is available at the CU, where the installer enters the Meter serial number. De-commissioning follows a similar process.
Communication between the meter and consumer unit is Power Line Carrier (PLC) the technology used is OFDM (Multi-carrier) which provides a more reliable data transfer success in varied environmental conditions.
Specification compliance
IEC 62055–41, 51 & 52 Standard Transfer Specification (STS) compliant with secure token used for recharge.
SANS 1524-1 Electricity Payment Systems, Part 1 Prepayment Meters
IEC 62055-31 Electricity Metering – Payment Systems, Part 31 Static Payment Meters for Active Energy.
NRS 049 Advanced Metering Infrastructure, Smart Metering Systems (with exceptions).
DSP 34-1635 Eskom requirements for Prepayment Meters
Tamper proof
The following tamper conditions can be detected:
- Magnetic interference.
- CU Bypass (Relay CU).
- Reverse energy.
- Terminal Cover open
The above conditions are configurable for recording & disconnection.
The meter unit is sealed for life.
The SSP DIN Meter is designed as a sealed for life meter. The main enclosure is ultrasonically welded, which protects from illegal access to the meter.
Measurement
Meter measures both forward and reverse energy. Forward energy register totals the forward + reverse energy consumption. Reverse energy register records reverse energy consumption only.
Instantaneous values are available for Voltage, Current, Active Power, Power Factor, Frequency and the internal temperature of the meter.
Communication
Optical port with 2-way communication in accordance with IEC62055-52
The addition of a uUSB port can be available with communication protocol in accordance with IEC62055-52
Configurable features
Low credit threshold.
Open load switch under the following conditions: Sag condition detected, i.e. power down; Tamper condition detected; Quality of supply over or under condition detected; Disconnection lockout condition.
Disconnection and re-connection timing can be specified by the customer and will be pre-set during manufacture.
Tamper conditions: On detection of a CU Relay bypass the behavior is configurable.
Maximum demand.
Event recording
| Event | No. of Occurrences | Date & Time stamp | Value |
| Tamper detection | Yes | ||
| Load Switch disconnection | Yes | ||
| Credit tokens accepted | Yes | ||
| Key change tokens accepted | Yes | ||
| Minutes of operation | Yes | ||
| Minutes since power up | Yes | ||
| Power down & Power up | Yes | Yes | Yes |
| Over & Under Voltage | Yes | Yes | Yes |
| Over & Under frequency | Yes | Yes | Yes |
| Over & Under Power | Yes | Yes | Yes |
| Over temperature | Yes | Yes | Yes |
| Zero credit | Yes | Yes | |
| External disconnection | Yes | Yes | |
| Load disconnection test | Yes | Yes | |
| Critical Meter failure | Yes | Yes | |
| Tamper | Yes | Yes | |
| Lock out | Yes | Yes | |
| Change of operational mode | Yes | Yes | |
| Clearing of meter registers | Yes | Yes | |
| Clearing of load profiles | Yes | Yes | |
| Re-configuration of the meter | Yes | Yes |
Product reliability
All products are designed for a 15 year life span under the specified operating conditions.
All products have 12 month warranty. Extended warranty periods can be offered.
The Meter Control Unit an Stand Alone CU are Eskom accredited.
Power Line Communication technology
Modern PLC technologies have developed with the advent of high bandwidth internet access and the desire to use the mains network for last mile access into consumer premises. The dominant and most reliable of these technologies is based on a multi carrier system using Orthogonal Multi-Frequency Division Multiplexing (OFDM). For high speed application like internet and video very wide bandwidths are used. For metering applications a very much narrower bandwidth is used and the frequency range of the carriers is within the frequency band dedicated to use by electrical utilities and their licensees (CENELEC A band).
The SSP DIN PLC meter makes use of this OFDM technology to eliminate interference from narrow band sources and further makes use of forward error correction algorithms and redundancy techniques to ensure reliable communication even in the face of severe interference from the likes of CFL’s, light dimmers and modern appliances.
Surge/lightning protection
The SSP DIN Meter design includes the use of Surge arrestors on both the Live In and Live Out circuits, protecting both itself and the supporting the protection to the sensitive devices in the home.
Product Longevity
The SSP DIN Meter is designed for a 15 year life expectancy. With careful consideration and analysis the components selected meet the necessary criteria to sustain the confidence in this specification.
Harsh environment
The SSP DIN Meter being bottom connect, sealed for Life and with restricted access to the internal operations of the meter, enable it to withstand various harsh climatic environments.