B21
MID energy meter, single-phase, direct connection up to 65 A
The B21 is Janitza's single-phase (1 + N) MID-certified energy meter for direct connection up to 65 A. It records active, reactive and apparent energy in four quadrants across two tariffs, and also shows instantaneous values such as voltage, current, power, frequency and power factor. At only 2 DIN modules wide it suits sub-metering of individual circuits, tenants or consumers, and is available with pulse outputs only or with an RS-485 (Modbus RTU) or M-Bus interface for connection to an energy monitoring system.
Key Features
- 01MID certified (module B + D), approved to IEC
- 02Single-phase (1 + N) direct connection up to 65 A
- 03Active, reactive and apparent energy, 4-quadrant measurement, 2 tariffs
- 04Measured values (V, A, W, Hz, PF) and alarm function
- 05Pulse outputs and tariff inputs; optional RS-485 (Modbus RTU) or M-Bus
- 062 DIN modules wide
Technical Specifications
B21
| Variants | B21 311-10J (14.01.353, pulse); B21 312-10J (14.01.354, RS-485); B21 313-10J (14.01.355, M-Bus) |
|---|---|
| Voltage inputs | 1 × 230 V AC; rated 220…240 V AC (-20…+15 %) |
| Current inputs | Direct connection; 0.25–5 (65) A |
| Accuracy class | Active energy B (cl. 1); reactive energy cl. 2 |
| Frequency | 50 or 60 Hz ± 5 % |
| Inputs / outputs | 2 inputs, 2 outputs; LED 1,000 pulse/kWh |
| Communication protocols | Pulse only, RS-485 (Modbus RTU) or M-Bus, by variant |
| Display | LCD, 6 digits |
| Dimensions | 35 × 97 × 65 mm (W × H × D); approx. 0.15 kg |
| Installation type | DIN rail, 2 modules |
| Operating temperature | -40 … +70 °C |
| Protection | IP20 on the terminals; IP51 in a protective housing (IEC 60529) |
| Certifications / standards | MID (module B + D), mechanical class M1, electromagnetic class E2; IEC 62053-21, IEC 62053-23, EN 50470-1/-3 |
Technical values are taken from the manufacturer's published documentation. Confirm against the current datasheet before ordering.
Downloads
Datasheets, manuals and technical documentation are available from the manufacturer's document centre, or on request from us.
Technical sources
- www.janitza.com/en/products/mid-energy-meter-and-measurement-system
- www.janitza.com/en/products/mid-energy-meter-and-measurement-system/technical-details
- www.janitza.com/en/products/mid-energy-meter-and-measurement-system/downloads
- assets.janitza.com/ce18jq9ih0x6/e2c1bdf081c3c153dd0f11/beacd5e26a701ce4737d52a805c972b3/janitza-bhb-b2x-en.pdf
- assets.janitza.com/ce18jq9ih0x6/2d439757b8d35ee2d440eb/33b6143bdb26f493771f94fe742a9722/mid_zaehler_b21_b23_b24_de.pdf
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