SGM-C8 Compact Meter

Product information

The SGM-C8 is characterized by the following features: 

• Case compliant with DIN standard for three-point mounting with module bay to hold an LMN adapter or tariff input module 
• Flexible measurement via shunts with intrinsic immunity to harmonics and external magnetic fields: +A (consumption meter) or -A (supply meter) with reverse running lock, +A/-A (bidirectional meter) or totalizing supply meter 
• Module bay for an optional LMN adapter with RS-485 bus interface for connection to a smart meter gateway or an optional tariff input module (dual tariff input) 
• PIN-protected data display and output 
• Front optical information interface for local data provision 
• Operation via optical request sensor and mechanical request button 
• Multi-functional display for meter data and historical data over 2 years 
• Sturdy, low-emission power supply 
• Output of readings and grid quality parameters (grid status data) 
• Optional eINFO interface  

Standard functions

In accordance with statutory provisions, the meter acts as a reliable and secure metering device for acquisition of billing-related active power quantities and grid-friendly measurement data and parameters, such as effective values of line voltage and current, power, phase angle and line frequency (grid status data). 

Active power is measured in both directions, with the following measurement modes being available: 

• Unidirectional meter (+A or -A) 
• Bidirectional meter (+A and -A) 
• Supply meter, totalizing without reverse running lock (-A) 

The current sensors used are robustly mounted, precise shunts, suitable for Class B accuracy.  The actual power values in all the phases are registered internally and are available over the data interfaces. Actual power values on all lines are logged internally and available over the data interfaces. The measurement mode is set at the factory in accordance with metrological requirements. 

The meter also provides the following grid status data (grid functions): 

• Active power (total active power P as well as individual phase values P_L1, P_L2, P_L3), calculated as an average over 1 second, resolution 0.1 W 
• Effective values of line and line-to-line voltages U_L1, U_L2, U_L3 calculated as average values over 1 second, accuracy 1% of measured value, resolution 0.1 V 
• Effective values of line currents I_L1, I_L2, I_L3 calculated as average values over 1 second, resolution 0.1 A, accuracy 1% of measurement 
• Phase angles φ_L1, φ_L2, φ_L3, accuracy/resolution 1° relative to the fundamental frequency 
• Line frequency f_line, accuracy 1%, resolution 0.1 Hz 

The daily, weekly, monthly and annual values of active power over a period of two years are recorded in the ring buffer as historical data and displayed under PIN protection. The front optical interface is used for local provision of measurement data and device information according to SML/COSEM at 1-second intervals This function is also PIN protected. PIN entry is via the front mechanical button or via the optical button. 

Optional Functions

An LMN interface (RS-485 interface) can be provided using an LMN adapter. It enables connection to a smart meter gateway and operates at a baud rate of 9.6 kbit/s. The protocols employed are SML/COSEM in the application layer. 

A dual tariff module is available as an option. The tariff registers in both power directions, as well as the current tariff, are shown on the display. Removing the terminal cover is detected as tampering and logged.