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How to Wire and setup Eastron SDM630MCT Three-Phase Meter

In this video, you will learn how to wire and set up Eastron SDM630MCT Three-Phase Meter with a current transformer (CT). Step by step description is mentioned below for your reference.  

Step 1: Understanding the Model 
Let's understand the model/part number: 
SDM stands for Sub Distribution Meter. 
630 represents the 3 Phase meter range. 
M indicates Modbus 485 serial communication interface. 
CT signifies Current Transformer, connected to each phase for current flow measurement.  

Step 2: Meter Orientation and Power Connections 
Locate the voltage reference terminals at the bottom of the meter: 
Terminal 1: Neutral 
Terminal 2: L3 
Terminal 3: L2 
Terminal 4: L1  
Supply these with 3-phase power via an inline 1A fast blow fuse for each phase. 
Connect auxiliary power supply: 
Terminals 5 and 6 are used to power the meter itself. 
The auxiliary power may be supplied via a circuit breaker or links to terminals 1 and 4. 
Terminal 7 (Live) and terminal 8 (Neutral) can be used to power other meters or loads.

Step 3: CT and Modbus Connections 
Locate terminals for pulse output, Modbus, and CT connections on the top of the meter. 
Connect CTs: 
Terminals 15-20 are for CT connection. 
Connect Phase L1 CT to terminals 19 (S2) and 20 (S1). 
Connect Phase L2 CT to terminals 17 (S2)and 18 (S1). 
Connect Phase L3 CT to terminals 15 (S2) and 16 (S1). 

Step 4: Setting CT Rate 
Determine the CT rate based on your CT specifications. 
Example: CT rated with an input of 200 Amps and output of 5 Amps, CT rate = 200/5 = 40. 
Enter CT settings: 
Hold down the E button. 
Using Up/Dn button, Enter password 1000. 
Use Enter button to move cursor 
Scroll through the menu until you see CT2. 
Set CT2 output/secondary to match CT (e.g., 5 Amp). 
Set CT rate to desired value (e.g., 40). 

Step 5: Modbus and Pulse Output Connections 
Terminals 12 GND, 13 B, and 14 A are for Modbus RS485 communication. 
Terminals 9, 10, and 11 are for pulse output.

Step 6: Final Checks 
Ensure all CTs are rated the same and connected correctly. 
Connect CTs to the correct terminals (S1 and S2). 
Orient CTs correctly on phase conductors (arrow denotes current flow direction). 
Ensure CT connections to the meter are correctly colour-oriented (black to S2, white to S1).