Eastron SDM630MCT 40mA DIN Rail Energy Meter

Key Features

• Bi-directional measurement (Import & Export)
• Two pulse outputs
• RS485 Modbus communication
• DIN rail mounting (35 mm)
• 40mA CT connection
• Accuracy better than Class 1 / Class B

Introduction

The SDM630MCT 40mA measures and displays electrical characteristics for single-phase two-wire (1p2w), three-phase three-wire (3p3w), and three-phase four-wire (3p4w) supplies. It measures energy in kWh and kVArh, and maximum demand can be recorded over preset intervals up to 60 minutes. The unit requires voltage and current inputs, with current input provided by external current transformers (CTs) with a 40 mA output. The unit supports a wide range of CTs, offering flexibility in operation. It features built-in pulse and RS485 Modbus RTU outputs. Configuration is password-protected.

The unit can be powered by a separate auxiliary supply (AC or DC) or directly from the monitored supply.

Unit Characteristics

The unit can measure and display:

• Line voltage and THD% for all phases
• Line Frequency
• Currents, Current demands, and Current THD% for all phases
• Power, Maximum Power Demand, and Power Factor
• Active energy imported and exported
• Reactive energy imported and exported

Password-protected set-up screens allow for:

• Password changes
• Supply system selection (1p2w, 3p3w, 3p4w)
• Demand Interval time configuration
• Resetting demand measurements
• Pulse output duration setting

Two pulse outputs provide real-time energy measurement. An RS485 output enables remote monitoring via another display or a computer.

Current Transformer Primary Current

The secondary current of the CT is fixed at 40 mA, while the primary current is optional and configurable.

RS485 Serial - Modbus RTU

This interface uses an RS485 serial port with Modbus RTU protocol for remote monitoring and control. Setup screens are available for configuring the RS485 port parameters.

Pulse Output

Two pulse outputs are provided to indicate real-time energy measurement. The constant for active energy is 3200 imp/kWh (Terminals 11 & 12). The pulse width for pulse 1 (Terminals 9 & 10) can be set via the setup menu.

Start-Up Screens

Upon startup, the unit displays:

• Screen 1: All display segments light up for a display check.
• Screen 2: Indicates the installed firmware version and build number.
• Screen 3: Performs a self-test and displays the result.

After a short delay, the screen will display active energy measurements.

Measurements and Button Operations

The unit is operated using four buttons:

• [U/I_esc]: Selects Voltage and Current display screens. In Set-up Mode, functions as "Left" or "Back".
• [M_up]: Selects Frequency and Power Factor display screens. In Set-up Mode, functions as "Up".
• [P_down]: Selects Power display screens. In Set-up Mode, functions as "Down".
• [E_enter]: Selects Energy display screens. In Set-up Mode, functions as "Enter" or "Right".

Voltage and Current Displays

Pressing the [U/I_esc] button cycles through different voltage and current display ranges:

• Phase to neutral voltages (3p4w)
• Phase to phase voltages (3p3w)
• Current on each phase
• Neutral current

THD% Displays

• Phase to neutral voltage THD% (3p4w)
• Current THD% for each phase

Frequency and Power Factor Displays

Pressing the [M_up] button cycles through:

• Frequency and Power Factor (total)
• Power Factor of each phase

Demand Displays

• Maximum Current Demand
• Maximum Power Demand

Power Measurements

Pressing the [P_down] button cycles through:

• Instantaneous Active Power in kW
• Instantaneous Reactive Power in kVAr
• Instantaneous Volt-amps in kVA

Energy Measurements

Pressing the [E_enter] button cycles through:

• Total active energy in kWh
• Total reactive energy in kVArh
• Imported active energy in kWh
• Exported active energy in kWh
• Imported reactive energy in kVArh
• Exported reactive energy in kVArh

Setting Up

To enter set-up mode, press and hold the [U/I_esc] button for 3 seconds until the password screen appears.

Password Entry

The setup is password-protected. The default password is '1000'. If an incorrect password is entered, the display shows 'PASS Err'.

Exiting Set-up Mode

To exit set-up mode, press the [U/I_esc] button repeatedly until the measurement screen is restored.

Set-up Entry Methods

Some menu items require a four-digit number entry (e.g., password, CT primary current), while others require selection from a list (e.g., supply system).

Menu Option Selection

1. Use the [M_up] and [P_down] buttons to select the desired menu item. Selection does not roll over.
2. Press [E_enter] to confirm the selection.
3. If an item flashes, it can be adjusted using the [M_up] and [P_down] buttons. If it does not flash, there may be a further sub-menu.
4. After selecting an option, press [E_enter] to confirm.
5. To return to a higher menu level, press [U/I_esc].
6. Once all settings are complete, press [U/I_esc] repeatedly to return to the main measurement screen.

Number Entry Procedure

1. The digit to be set flashes and is adjusted using the [M_up] and [P_down] buttons.
2. Press [E_enter] to confirm each digit.
3. After setting the last digit, press [U/I_esc] to exit the number setting routine.

Communication Settings (RS485)

The RS485 port can be configured for Modbus RTU protocol. Parameters are set via the front panel.

RS485 Address

The Modbus Address can be set from 001 to 247.

Baud Rate

Available Baud Rates: 2.4k, 4.8k, 9.6k (default), 19.2k, 38.4k.

Parity

Options: NONE (default), ODD, EVEN.

Stop Bits

Options: 1 or 2. Stop bit can only be changed to 2 when Parity is set to NONE.

CT and PT Settings

CT (Current Transformer)

CT1: Sets the primary current of the CT connected to the meter. Default is 300A, range 0005 to 9999.

CT2: Secondary CT is fixed at 40 mA and cannot be set.

PT (Potential Transformer)

PT2: Sets the secondary voltage of the Voltage Transformer (PT). Range is 100V to 500V. For example, setting the ratio to 100 means the primary voltage equals the secondary voltage x 100.

Pulse Output Configuration

This section allows configuration of the pulse output behavior.

• Pulse Output Units: Can be set to Total kWh (default) or Total kVArh.
• Pulse Rate: Sets the energy represented by each pulse. Options include 1 pulse per 0.01 kWh/kVArh, 0.1 kWh/kVArh, 1 kWh/kVArh, 10 kWh/kVArh, 100 kWh/kVArh, 1000 kWh/kVArh.
• Pulse Duration: The pulse width can be set to 200ms, 100ms (default), or 60ms.

Pulse output 2 is non-configurable and fixed to total kWh with a constant of 3200 imp/kWh.

DIT (Demand Integration Time)

Sets the time period (in minutes) for integrating current and power readings for maximum demand measurement. Options: OFF (0), 5, 8, 10, 15, 20, 30, 60 minutes.

Backlit Set-up

Configures the duration of the blue backlit display. The default lasting time is 60 minutes. Options: 0 (always on), 5, 10, 30, 60, 120 minutes. If set to 5, the backlight will turn off after 5 minutes of inactivity.

Supply System Selection

Sets the type of power supply being monitored. Options include 1P2W, 3P3W, and 3P4W.

Change Password

Allows the user to change the default password. The process involves entering the current password and then the new password digit by digit.

CLR (Clear Maximum Demand)

Resets the maximum demand values for current and power.

Reverse Connected Current Inputs Correction

This feature allows correction for reversed phase A current input. The setting can be changed from 'Fwd' (forward) to 'Rev' (reverse).

Specifications

Measured Parameters

The unit monitors and displays parameters for 1p2w, 3p3w, or 3p4w supplies:

• Voltage: 230V a.c. (±20%) phase-to-neutral (Not for 3P3W); 400V a.c. (±20%) phase-to-phase (for 3P3W).
• THD%: Percentage total voltage harmonic distortion for each phase to N (not for 3p3w); Percentage voltage THD% between phases (three-phase only); Current THD% for each phase.
• Frequency: Hz.
• Instantaneous Power: Active Power (0-3600 MW), Reactive Power (0-3600 MVAr), Volt-amps (0-3600 MVA).
• Maximum Demand: Maximum demanded power and maximum neutral demand current since last reset.
• Power Factor: Measured power factor.
• Energy: Imported/Exported active energy (0-9999999.9 kWh), Imported/Exported reactive energy (0-9999999.9 kVArh), Total active energy, Total reactive energy.

Measured Inputs

• Voltage Inputs: 4-way fixed connector, 2.5 mm² wire capacity. Supports 1p2w, 3p3w, or 3p4w unbalanced. Line frequency measured from L1 or L3 voltage.
• Current Inputs: Three current inputs (six terminals), 2.5 mm² wire capacity for external CTs. Nominal rated input current: 333 mV a.c. Rms. Maximum torque: 0.4 Nm.

Accuracy

• Voltage: 0.5% of range maximum
• Current: 0.5% of nominal
• Frequency: 0.2% of mid-frequency
• Power Factor: 1% of unity (0.01)
• Active Power (W): ±1% of range maximum
• Reactive Power (VAr): ±1% of range maximum
• Apparent Power (VA): ±1% of range maximum
• Active Energy (Wh): Class 1 IEC 62053-21
• Reactive Energy (VARh): Class 2 IEC 62053-23
• Total Harmonic Distortion: 1% up to 31st harmonic
• Response Time: 1s typical to >99% of final reading at 50/60Hz.

Auxiliary Supply

Input: 100-277 V a.c., 50/60 Hz ±10% or 140-392 V d.c. ±20%.

Consumption: <10W.

Connection: Two-way fixed connector, 2.5 mm² wire capacity.

Interfaces for External Monitoring

• RS485 Communication: Programmable for Modbus RTU protocol.
• Pulse Output: Indicates real-time measured energy (configurable).
• Non-configurable Pulse Output: Fixed at 3200 imp/kWh for total active energy.

Modbus configuration (Baud rate, etc.) and pulse output assignments (kWh/kVArh) are configured via the Set-up screens.

RS485 Output for Modbus RTU Configuration

• Baud Rate: 2400, 4800, 9600 (default), 19200, 38400.
• Parity: None (default), Odd, Even.
• Stop Bits: 1 or 2.
• RS485 Network Address: 3-digit number, 001 to 247.
• Modbus™ Word Order: Automatically set to normal or reverse; not configurable from the set-up menu.

Reference Conditions of Influence Quantities

Accuracy is verified under nominal values (within specified tolerance) for:

• Ambient temperature: 23°C ±1°C
• Input frequency: 50 or 60 Hz ±2%
• Input waveform: Sinusoidal (distortion factor <0.005)
• Auxiliary supply voltage: Nominal ±1%
• Auxiliary supply frequency: Nominal ±1%
• Auxiliary supply waveform: Sinusoidal (distortion factor <0.05)
• Magnetic field of external origin: Terrestrial flux

Environment

• Operating Temperature: -40°C to +70°C
• Storage Temperature: -40°C to +70°C
• Relative Humidity: 0 to 95% (non-condensing)
• Altitude: Up to 2000 m
• Warm-up Time: 5 s
• Vibration: 10 Hz to 50 Hz, IEC 60068-2-6, 2 g
• Shock: 30 g in 3 planes

Dimensions and Installation

The meter is designed for DIN rail mounting (35 mm). The dimensions are approximately 94.5 mm (width) x 72 mm (height) x 65 mm (depth).

Wiring Diagrams

The document includes wiring diagrams for:

• Three Phase Four Wire (3CT)
• Three Phase Three Wire (2CT)
• Single Phase Two Wire (1CT)

These diagrams illustrate the connections for voltage and current inputs, auxiliary power, and RS485 communication.

Zhejiang Eastron Electronic Co., Ltd. - Product Specification (Current Transformer)

Product Name: Open and Closing Current Transformer

Product Specification: ESCT-TA16 120A/40mA

Main Technical Parameters

Primary, Secondary, and Polarity Definitions

• Primary Definition: Primary penetration input and secondary lead output.
• Same Name Definition: P1 into, P2 out of the transformer.
• Electrical Schematic Diagram: Shows the transformer's electrical connections with P1, P2, 120A primary, and White/Black 40mA secondary leads.

Main Production Technical Requirements

• Shell Color: Black.
• CT Wire Requirement: 2 * 0.3 mm², black and white wires, 1.0 m length.
• Overall Dimensions: Provided in a diagram.
• CT Error Requirements: Tables detailing Current Error and Phase Error at different current levels for 0.5 accuracy class.

Contact Information

Zhejiang Eastron Electronic Co., Ltd.
No.52, Dongjin Road, Nanhu, Jiaxing, Zhejiang, 314001, China
Tel: +86-573-83698881
Fax: +86-573-83698883
Email: sales@eastrongroup.com
Website: www.eastrongroup.com