The first shunt-based DC energy reference meter for power classes up to 500 kW that is compliant with calibration law

The IEM-DCC-500 is a high-precision, DC energy reference meter that complies with German measurement and calibration law. The area of application of the IEM-DCC-500 in particular extends to the public DC charging infrastructure of electric vehicles with power classes of up to 500 kW. The unidirectional reference meter allows for current ranges up to 500 A and voltage ranges up to 1,000 V. Due to the shunt measurement technology used, a very compact design was created for this power range, which ensures tamper detection. Combined with the SML-based communication protocol with the meter modes EDL 40 and 40++, as well as the digital signing of the information, it can be used as a basis for billing systems in public charging stations. The IEM-DCC-500 signs its data tuple consisting of the absolute meter value, transaction ID, legal time and meter status with a private key and sends this billing-related data to a remote station previously identified as secure. All billing processes directed towards the user of the public charging device are then based on the database collected in the back-end system.

The successfully issued type examination certificate from the Physikalisch-Technische Bundesanstalt [National Metrology Institute of the Federal Republic of Germany] confirms an accuracy class A (EN 50470) or class B (EN 50470) for the IEM-DCC-500 depending on the respective application conditions and allows Isabellenhütte to declare its EC conformity. In order to only bill the charging device users for the energy actually consumed at the energy transfer point, the IEM-DCC-500 supports four-wire measurement, as well as the option to store the specific charging cable parameters. The later enables the correction of the measured value by the charging cable losses in accordance with the calibration law.


Key features of the IEM-DCC-500:
•    Current measurement range: 500 A (nominal), up to 600 A (maximum)
•    Voltage range up to 1,000 V (maximum)
•    Operating temperature range from -25 to +75°C
•    Housing protection class IP30, sealable and flame-protected (UL94-V0)
•    Extended correction of charging cable losses under the patent of ISAscale®
•    Integrated TFT display with different display levels on photodiode input
•    SML-based communication protocol with the meter modes EDL 40 and EDL 40 ++