Circutor CVM-E3-MINI

Compatibility

Compatible with EpiSensor Edge over Modbus TCP or Modbus RTU

The CVM-E3-MINI is compatible with EpiSensor Edge over its RS-485 Modbus RTU port, read through a ZMB-31 Modbus Interface or a Gateway serial port, and the WiEth versions over Modbus TCP on their Ethernet port. Circutor documents FC03 and FC04 reads, a hexadecimal map with units and scaling, and its own example request and reply for L1 voltage, and states that the same map applies to the WiEth versions over Modbus TCP.

CVM-E3-MINI-ITF-485-IC, code M56414, and the MC, FLEX and WiEth versions that share instruction manual M170B01-03-25B (July 2025). Site check: compare the first L1 voltage read with the display; the same read confirms the map and the word order. Read-only monitoring: no FC05 delete commands and no FC10 configuration or password writes. BACnet MS/TP is a separate protocol choice on the same RS-485 port.

Connect it with

• Modbus Interface ZMB-3X From €399 ex VAT Configure
• Gateway ZGW-20 From €899 ex VAT Configure
• Evaluation Gateway on a Raspberry Pi Edge with one device licensed Free Set up

Models

Specifications

A three-module DIN-rail analyser for low and medium voltage distribution boards, measuring four quadrants on balanced or unbalanced three-phase, two-phase and single-phase circuits. The order code fixes the current input; the setup menu fixes the measurement system, transformer ratios and the protocol on the RS-485 port.^1, 2

Exact reference

CVM-E3-MINI-ITF-485-IC, code M56414: .../5 A or .../1 A inputs, RS-485 with Modbus RTU or BACnet, one transistor output, one digital input.¹

Current inputs (ITF)

Three inputs for .../5 A or .../1 A transformers, set in the setup menu. Measures from 10 mA to 6 A; CAT III 300 V.²

Voltage inputs

Rated 300 V phase to neutral and 400 V phase to phase, measuring from 11.5 V phase to neutral at 45 to 65 Hz. CAT III 300 V.²

Measurement systems

Three-phase 4-wire, three-phase 3-wire, Aron, two-phase 3-wire, and single-phase 2-wire phase to phase or phase to neutral.²

Auxiliary supply

M56414: 207 to 253 VAC (230 V ±10%), 50/60 Hz, 4 VA. The manual also lists 100 to 240 VAC and 100 to 240 VDC supplies on some versions, so check the label.^1, 2

Accuracy (ITF)

Voltage and current 0.5% ±1 digit, active and apparent power 0.5% ±2 digits. Active energy class 1 below 0.1 In and class 0.5 (.../1 A) or 0.5S (.../5 A) above it, as the manual's table gives them; reactive energy class 2.²

RS-485

Terminals A (A+), B (B-) and S, the reference shared with the digital input. Modbus RTU or BACnet MS/TP, one at a time. Up to 32 devices and 1200 m per bus.²

Serial settings

9600 or 19200 bit/s, plus 38400, 57600 and 115200 on software v2.xx; no, even or odd parity; 7 or 8 data bits; 1 or 2 stop bits. Peripheral number 1 to 255, at most 247 on v2.xx. Defaults: peripheral 1, 19200 bit/s, no parity, 8 data bits, 1 stop bit.²

Ethernet (WiEth versions)

RJ45, 10BaseT or 100BaseTX, Modbus TCP and web server, DHCP on by default; 2.4 GHz Wi-Fi (IEEE 802.11 b/g/n).²

Inputs and outputs

One NPN transistor output (24 V, 50 mA, up to 16 pulses per second) for alarms or energy pulses, and one optoisolated digital input for tariff selection, logic state or pulse counting.²

Environment

Operating -10 to +50 °C and storage -30 to +80 °C in the manual; the M56414 product page gives -5 to +45 °C working. 5 to 95% relative humidity without condensation, up to 2000 m, indoor use.^1, 2

Enclosure

DIN rail, three modules, self-extinguishing V0 plastic. IP30, front IP40, IK08. 52.5 × 118 × 74 mm, 300 g. A 72 × 72 mm panel adapter is available.^1, 2

Interface

Documented measurements and integration boundaries for CVM-E3-MINI.

• Circutor publishes two layouts of the same measurements. Map 1 keeps the CVM-MINI addresses; Map 2 uses the CVM-C10 addresses plus 0x1000, and Circutor recommends it for a new integration. Use one map per meter and do not mix them.
• All addresses are hexadecimal and go on the wire as printed. Read with FC03 or FC04; each value takes two registers, high word first, as Circutor's own example reply shows. One request may carry at most 20 variables (40 registers).
• Map 2 phase voltage L1, L2 and L3 at 0x1000, 0x1010 and 0x1020 (decimal 4096, 4112, 4128): V × 10. Line voltages V12, V23 and V31 at 0x103E, 0x1040 and 0x1042, V × 10.
• Map 2 current L1, L2 and L3 at 0x1002, 0x1012 and 0x1022 (decimal 4098, 4114, 4130) in mA; neutral current at 0x1044 (decimal 4164) in mA.
• Map 2 active power L1, L2 and L3 at 0x1004, 0x1014 and 0x1024, and three-phase active power at 0x1030 (decimal 4144): all in W, although the symbol column says kW. Three-phase inductive and capacitive reactive power at 0x1032 and 0x1034 in var, apparent power at 0x1036 in VA.
• Map 2 three-phase power factor at 0x1038 and cos φ at 0x103A, × 100. Frequency at 0x103C (decimal 4156) in Hz × 100.
• Map 2 total consumed active energy at 0x10DC (decimal 4316) in kWh, with a separate Wh register at 0x10DE. Total generated active energy at 0x10F0 (decimal 4336) in kWh, with Wh at 0x10F2. Tariff 1 and tariff 2 consumed energy start at 0x105E and 0x1088.
• Per-phase energies are at the same addresses in both maps: total consumed active energy for L1, L2 and L3 at 0x1440, 0x14A0 and 0x1500 in kWh, with Wh in the next pair.
• Map 1, for systems already built for a CVM-MINI: L1 voltage at 0x0000 (V × 10), L1 current at 0x0002 (mA), three-phase active power at 0x001E (W), frequency at 0x0028 in Hz × 10 rather than × 100, and total consumed active energy at 0x01E0 in kWh with Wh at 0x0172. The manual prints 0x0172 out of step with its tariff columns (Wh at 0x018E and 0x01B8), so compare that register with the display before relying on it.
• Power status at 0x07D1 (FC04): bit 0 consumed, bit 1 generated, bit 2 inductive, bit 3 capacitive. The serial number is at 0x05AA to 0x05B0 (FC04).
• On software v2.xx, Circutor asks for a response time-out of at least 200 ms and at least 100 ms between frames.
• Writes in the map: FC05 commands delete maximum and minimum values, energies (0x0834 for three-phase energies, 0x0898 for every deletable value) and restore defaults (0x0BB8); FC10 writes transformer ratios from 0x2710, serial settings from 0x2742 and the programming password at 0x2B70. Keep all of them out of a monitoring client.

Setup

1. Identify the analyser

   Read the order code on the side label and confirm CVM-E3-MINI-ITF-485-IC (M56414) or the MC, FLEX or WiEth version you have. Note the software version: v1.xx and v2.xx differ in speeds, peripheral range and timing, and cannot be upgraded from one to the other.

2. Check the measurement setup

   Confirm the measurement system and the CT primary and secondary with the installer, and check that the analyser's setup matches them. The register values are scaled by the programmed ratios.

3. Select Modbus and record the serial settings

   On the RS-485 communications screen choose Modbus rather than BACnet, then record the speed, peripheral number, parity, data bits and stop bits. The analyser restarts when you leave the menu after changing them.

4. Wire the bus

   Connect A(+), B(-) and the S reference with shielded twisted pair of at least three wires, give each analyser its own peripheral number, and keep the bus within 32 devices and 1200 m.

5. Read L1 voltage first

   Send FC04 (or FC03) to 0x1000 for two registers, as in the worked read below. Combine the high word first and divide by 10 for volts, then compare with the L1 voltage on the display.

6. Add current, power and energy

   Add current at 0x1002 in mA, three-phase active power at 0x1030 in W and total consumed energy at 0x10DC in kWh with the Wh register at 0x10DE. Keep consumed and generated energy as separate series and leave every FC05 and FC10 address out of the configuration.

Common questions

Should I use Map 1 or Map 2?

Circutor recommends Map 2 for a new integration. It is the CVM-C10 layout with 0x1000 added to every address, so a configuration built for a CVM-C10 needs only that offset. Use Map 1 only to match a system already written for a CVM-MINI, and note that Map 1 frequency is Hz × 10 while Map 2 is Hz × 100.²

Is 0x1000 the address I enter, or 41001?

The manual states that every Modbus address is hexadecimal, and its example frame sends the address as printed. Enter 0x1000 (decimal 4096) in a client that takes zero-based addresses. A client with one-based labels calls it 34097 for FC04 or 44097 for FC03. 41001 would read 1000 as a decimal number; 0x1000 is 4096.²

Is active power in kW or W?

W. The symbol column says kW 1 and kW III, but the units column gives W for active power, var for reactive power and VA for apparent power. Divide by 1000 only if the destination expects kW.²

Can Edge read a CVM-E3-MINI over Ethernet?

Only the WiEth versions have Ethernet. Circutor states that the same map is valid over Modbus TCP on them. The RS-485 versions such as M56414 are read over Modbus RTU through a ZMB-31 or a Gateway serial port.^1, 2

Can the RS-485 port run BACnet and Modbus at once?

No. The RS-485 communications screen selects Modbus or BACnet MS/TP for the one port. This guide covers the Modbus RTU selection.²