Hager ECR300C

Three-phase energy meter

The ECR300C is a four-module, 3P+N meter for external 1 A or 5 A current transformers. Hager publishes the RS-485 settings, identity fields, instantaneous values and energy registers. Edge can read those operational values over Modbus RTU, but that monitoring path is not a revenue or settlement metering system.

  • Modbus RTU

Three-phase energy meter

Compatibility

Compatible for read-only Modbus RTU monitoring

Hager publishes an exact ECR300C product record, a model manual and Modbus table revision 1.14. The table identifies the ECR300C as a 3P_CT Modbus model and documents function 03 reads for identity, instantaneous measurements and energy.

ECR300C with a verified product code, firmware revision and external CT ratio. Use one commissioned read-only Modbus RTU client path. Exclude tariff changes, network-setting changes, partial-energy resets and every other write. Preserve the meter and installation controls required for any legally relevant energy total.

Connect it with

When the ECR300C RS-485 terminals can join a correctly engineered, read-only Modbus segment

  • Modbus
  • Edge
  • Platforms
Three-phase energy meter
Interface
Gateway
Edge
Output
ECR300CHager ECR300C
Isolated serial interfaceApproved RS-485-to-host adapter
ZGW-20 GatewayHosts Edge locally
EpiSensor EdgeModbus client + register map
Customer platformMQTT · API · files
Modbus RTU · RS-485
Isolated serial
Runs locally
Optional onward data
Match the configured address, baud rate, parity and stop bits. Hager calls for a 120 ohm termination resistor at each end of the line. Keep function 06 and 16 writes outside the Edge client and validate the exact meter identity before collecting measurements. The customer-platform output is optional; Edge remains the local system of record.

Models

Download
ModelsInterfaceRoute into Edge
ECR300CScrew-terminal Modbus RTU, 3P+N, external 1 A or 5 A CT input, MID variantUse this guide only after identity registers return ECR300C and the installed CT ratio is recorded.
ECR301C and ECR302CRelated 3P_CT models with different market or three-phase energy-summation scopeTreat as separate variants. Do not infer billing scope or energy behaviour from ECR300C.
ECA300C familyAgardio RJ45 connection rather than the ECR300C screw-terminal interfaceUse the exact ECA model and connection documentation instead of this wiring path.

Specifications

The ECR300C is a CT-connected meter. Its displayed and primary-side Modbus values depend on the commissioned CT ratio, while the map also provides a separate secondary-side table. Mixing those two groups would create a large scaling error.23

Measurement system
Three-phase 3P+N meter with external 1 A or 5 A current transformers12
CT range
Primary setting 1 to 1,200 A for /1 A CTs or 5 to 6,000 A for /5 A CTs2
Voltage range
92 to 276 V phase-neutral and 160 to 480 V phase-phase1
Serial interface
Three-wire RS-485 Modbus RTU; address 1 to 247; 1,200 to 38,400 bit/s; configurable parity and stop bits12
Energy calculation
ECR300C uses the documented magnitude summation method for three-phase energy3
Environment
-25 to +55 °C operating range; IP20 device enclosure; DIN-rail installation1

Interface

Documented measurements and integration boundaries for ECR300C.

  • Vendor, product code, software version, hardware version, serial number and production date from the identity block.
  • Phase-to-neutral and phase-to-phase voltage, phase current, neutral current and frequency.
  • Active, reactive and apparent power by phase and in total, with the documented sign convention retained.
  • IEC and IEEE power-factor values kept distinct rather than merged into one unsigned percentage.
  • Imported and exported active energy, reactive energy, tariff totals and partial totals supported by the installed firmware.
  • CT primary and secondary configuration recorded beside every current, power and energy stream.

Assessment

Exact Hager ECR300C with verified firmware, CT configuration and Modbus RTU settings; no writes and no claim that Edge data is a legal billing or settlement record.

InteroperabilitySupported with conditions
The exact model and a revisioned Modbus map are published, subject to correct serial settings, identity and firmware.13
AccuracySupported with conditions
Electrical and energy groups are documented, but CT setup, primary-versus-secondary tables and legal-use boundaries must be retained.23
SecurityLimited
Modbus RTU provides no peer authentication or encryption and the map contains writable groups. Physical, serial and client write controls are required.23
ReliabilitySupported with conditions
The map defines identity, error values and firmware-dependent energy availability; the site must retain revision and detect invalid or stale reads.3
RuggednessSupported with conditions
Temperature and IP20 enclosure limits are published. The meter still requires a suitable panel and correctly rated measurement circuit.1
ScalabilitySupported with conditions
Addressed RS-485 supports a multi-device segment, subject to one leader, unique addresses, physical-layer design and bounded polling.2
LifecycleSupported with conditions
Hager publishes the exact product record, manual and revisioned map. The installed firmware, map and CT configuration remain site records.123

Setup

Read the L1-N voltage without an address shift

Revision 1.14 places L1-N voltage at decimal address 45056, hexadecimal 0xB000, in the function 03 instantaneous-measurement block. It is one unsigned 16-bit register scaled by 100.

Function
03, Read Holding Registers
PDU address
45056 decimal (0xB000)
Length and type
1 register, unsigned 16-bit integer
Unit and scale
V/100
Example
Raw 23004 means 230.04 V

Acceptance: Send the table's literal address once. If a commissioning tool displays 40001-style references, verify its conversion to PDU offset 45056 instead of adding or subtracting one by habit. Compare the result with the meter display.

  1. Confirm the exact meter

    Record ECR300C from the front and verify the identity block over Modbus. Keep the serial number, software version, hardware version and the retained revision 1.14 map with the point configuration.

  2. Record the measurement circuit

    Document the 3P+N voltage wiring, CT primary and secondary values, CT polarity and phase assignment. Confirm whether collected values are the primary-side or separate secondary-side registers.

  3. Commission the RS-485 segment

    Match address, baud rate, parity and stop bits. Use suitable cable, isolation and reference conductors, with 120 ohm termination at the two physical ends. Avoid duplicate addresses and a second Modbus leader.

  4. Start with read-only identity and voltage

    Read the identity block and one phase voltage with function 03. Compare the decoded value with the simultaneous display before importing current, power or energy groups.

  5. Reconcile energy without changing the meter

    Keep import, export, tariff and partial totals separate. Compare interval deltas with the display and an upstream reference. Do not issue partial-reset, tariff or communications writes from the monitoring client.

Common questions

Can Edge read the Hager ECR300C over Modbus?
Yes, as a read-only protocol integration. Hager publishes Modbus RTU identity, instantaneous-measurement and energy tables for the ECR300C family. The exact meter identity, firmware, CT ratio and address settings still need commissioning.13
Does reading a MID meter through Edge create a billing meter?
No. Hager limits the MID statement to active energy and states that only the total active-energy register is for billing. An Edge copy, interval series or calculation is operational monitoring data unless a separate legal-metrology design establishes otherwise.2
Are ECR300C current and power values already scaled to the CT primary?
The main instantaneous table reports primary-side current and power for 3P_CT meters, and the map also contains separate secondary-side tables. Record which table is used and do not apply the CT ratio twice.3
Can the monitoring client reset partial energy or change tariffs?
This guide excludes every write. The Hager protocol supports write functions and documents reset and configuration groups, so the client and network must be constrained to the approved read-only point set.23

Sources

  1. ECR300C product page (opens in a new tab) Hager
  2. ECR300C user instructions 6LE005422Ad (opens in a new tab) (PDF) Hager
  3. Modbus Tables Summary revision 1.14 (opens in a new tab) (PDF) Hager

Further reading

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