Specifications:
The CIRWATT B 502 is a multi-function three-phase meter designed for indirect connection. It operates at nominal voltages of 3 x 230 (400) V, 3 x 127 (230) V, and 3 x 63.5 (110) V, with a tolerance range of 80% to 115% Un. The power consumption is less than 2 W and 10 V·A, and it supports frequencies of 50 or 60 Hz. The meter measures voltage asymmetrically and has a voltage consumption of less than 2 W and 10 V·A. Current measurement options include nominal reference currents of 1 (2) A, 1 (6) A, 2.5 (10) A, and 5 (10) A, with a start-up current of less than 0.001 x Iref and a minimum current of less than 0.01 x Iref. The accuracy class for active energy is EN 50470 (Class C) and IEC 62053-22 (Class 0.2S), while for reactive energy, it is IEC 62053-23 (Class 0.5, 1, or 2).

Memory and Battery:
The meter uses non-volatile memory for data storage and serial flash for setup and events. It is equipped with a lithium battery with a working life of over 20 years at 30 ºC.

Clock and Environmental Influence:
The clock uses a Gregorian calendar and a temperature-compensated oscillator, with an accuracy of less than 0.5 s/day at 23 ºC. The operating temperature range is -40 to +70 ºC, and the storage temperature range is -40 to +85 ºC. The temperature coefficient is less than 15 ppm/K, and the maximum humidity is 95%.

Insulation and Display:
The meter has an insulating voltage of 4 kV at 50 Hz for 1 minute and an impulse voltage of 6 kV. It has a protection degree of II (IEC 62052-11). The LCD display can show up to 8 data digits, each 8 mm in size, and can be read without voltage.

Application:
The CIRWATT B 502 is designed for high voltage installations requiring strict billing systems, different load profiles, and communications. It is adaptable to customer requirements and is suitable for installations with high energy consumption or generation.

Features:
The meter includes an optical communications interface with serial, two-directional hardware, and supports protocols like REE based on IEC 870-5-102. It has a tampering detector with a micro-switch to detect intrusions without voltage. The construction features include asymmetrical connection and DIN standard dimensions. The IP degree is IP 51 (IEC 60529).

Communications and Expansion:
The meter supports various communication interfaces, including RS-232, RS-485, and Ethernet, with options for relay outputs and impulse inputs. Expansion cards can be configured for additional functionalities like earth leakage measurement.

Dimensions:
The meter's dimensions are specified with options for wire cover configurations.