Installation

READ the safety warnings below before proceeding. Installation must be performed by a qualified electrician.

Safety Warnings

• CAT III — Distribution level measurement. Lethal voltages present.
• Disconnect all power before installation. Follow lock-out/tag-out (LOTO) procedures.
• Verify absence of voltage before touching terminals.

Package Contents

1. HT-8WAY DIN-rail enclosure with SDM630MCT-RC meter pre-installed
2. 3x ESCT-RC Rogowski coils (size per order)
3. ESP32-C3 IoT controller (pre-wired to meter RS485)
4. RS485 communication cables
5. Cable glands for enclosure entry
6. This manual

Step 1: Mount the Enclosure

Mount the HT-8WAY enclosure on a 35mm DIN rail in the distribution panel:

1. Select a location accessible for maintenance, with adequate ventilation
2. Ensure minimum clearance: 50mm above/below for wiring
3. Snap enclosure onto DIN rail
4. Secure with DIN rail clips

Step 2: Wire Voltage Connections

Connect voltage inputs to terminals 1–4:

Terminal	Connection
1	Phase L1 (Line 1)
2	Phase L2 (Line 2)
3	Phase L3 (Line 3)
4	Neutral N

For 3P4W (default): Connect all 4 terminals.

For 3P3W: Connect terminals 1, 2, 3 only (no neutral).

For 1P2W: Connect terminal 1 (L) and terminal 4 (N) only.

Step 3: Wire Auxiliary Power

Connect auxiliary power to terminals 5–6:

• Terminal 5: Live (85–277V AC)
• Terminal 6: Neutral

The meter powers on when auxiliary power is applied. Display should light up within 3 seconds.

Step 4: Install Rogowski Coils

Install the 3 Rogowski coils on the phase conductors:

1. Open the Rogowski coil by releasing the latch
2. Place the coil around the conductor (L1 for CT1, L2 for CT2, L3 for CT3)
3. Close the coil completely — ensure the latch clicks shut with no gap
4. Verify orientation: The arrow on the coil must point in the direction of current flow (source to load)

Connect Rogowski coil cables:

• CT1 (L1) -> Terminals 15, 16
• CT2 (L2) -> Terminals 17, 18
• CT3 (L3) -> Terminals 19, 20

Step 5: Wire RS485 (Optional)

If using external Modbus master or daisy-chaining multiple meters:

Terminal	Connection
9	RS485 D+ (Data+)
10	RS485 D- (Data-)
11	RS485 Shield/GND
12–14	Not used

Use twisted-pair cable. Install 120-ohm termination resistor at each end of the bus for runs >10m.

Step 6: Wire Pulse Outputs (Optional)

Terminal	Connection
7	Pulse output 1 (Active energy)
8	Pulse output 2 (Reactive energy)

Pulse outputs are opto-isolated open-collector. Maximum: 27V DC, 27mA.

Terminal Block Reference

Terminals	Function
1–4	Voltage inputs (L1, L2, L3, N)
5–6	Auxiliary power (L, N)
7–8	Pulse outputs (Active, Reactive)
9–14	RS485 Modbus (D+, D-, Shield)
15–20	Rogowski coil inputs (CT1, CT2, CT3)

Post-Installation Checklist

• [ ] All voltage connections secure and torqued
• [ ] Auxiliary power connected and meter display active
• [ ] Rogowski coils properly installed (correct orientation, fully closed)
• [ ] CT cables connected to correct terminals (CT1->15/16, CT2->17/18, CT3->19/20)
• [ ] Cable glands tightened
• [ ] Enclosure cover secured
• [ ] No exposed conductors

Product Photos