Energy Meters
Installation & Wiring Guide
DIN rail mounting, CT installation, RS485 wiring, and commissioning of HPzenAi energy meters.
Installation Video Guide
Watch the complete installation walkthrough before starting. The video covers DIN rail mounting, CT clamping, RS485 wiring, and gateway commissioning.
Tools Required
Gather these tools before starting. A qualified electrician must perform all wiring inside the electrical panel.
Tool Checklist
| Preview | Quantity | Item | Details |
|---|---|---|---|
| × 1 | Flat-Head Screwdriver | For tightening terminal block screws on the energy meter and gateway | |
| × 1 | Wire Strippers | To prepare RS485 cable ends and power supply leads before termination | |
| × 1 | DIN Rail Cutters or Hacksaw | To cut 35 mm DIN rail to length if a new section is being installed | |
| × 1 | Multimeter | To verify 12V DC supply voltage and confirm RS485 continuity before power-on | |
| As required | RS485 Shielded Twisted-Pair Cable | 2-core shielded cable for RS485 communication — not included, sourced separately | |
| As required | Cable Ties / Cable Duct | For neat cable management inside the electrical panel |
Flat-Head Screwdriver
For tightening terminal block screws on the energy meter and gateway
Wire Strippers
To prepare RS485 cable ends and power supply leads before termination
DIN Rail Cutters or Hacksaw
To cut 35 mm DIN rail to length if a new section is being installed
Multimeter
To verify 12V DC supply voltage and confirm RS485 continuity before power-on
RS485 Shielded Twisted-Pair Cable
2-core shielded cable for RS485 communication — not included, sourced separately
Cable Ties / Cable Duct
For neat cable management inside the electrical panel
What's in the Box
Verify all items are present before beginning installation. Contact support if anything is missing or damaged.
Included Items
| Preview | Quantity | Item | Details |
|---|---|---|---|
| × 1 | Energy Meter Unit | Main DIN rail-mounted meter body with LCD display | |
| × 1 or × 3 | Split-Core CT(s) | 60A split-core clamp-on current transformer — 1× for EM-1P-60A, 3× for EM-3P-60A | |
| × 1 set | CT Connection Cables | Pre-terminated CT leads for connecting CTs to the meter input terminals | |
| × 1 | DIN Rail Mounting Clip | Standard 35 mm DIN rail mounting clip (integrated into meter body) | |
| × 1 | Installation Guide | Printed quick-reference card for mounting, wiring, and commissioning |
Energy Meter Unit
Main DIN rail-mounted meter body with LCD display
Split-Core CT(s)
60A split-core clamp-on current transformer — 1× for EM-1P-60A, 3× for EM-3P-60A
CT Connection Cables
Pre-terminated CT leads for connecting CTs to the meter input terminals
DIN Rail Mounting Clip
Standard 35 mm DIN rail mounting clip (integrated into meter body)
Installation Guide
Printed quick-reference card for mounting, wiring, and commissioning
CT Installation — Clamping the Current Transformer
Split-core CTs clamp around the phase conductor without cutting any wires. The load does not need to be switched off for CT installation — but all panel work must be performed by a qualified electrician.
Steps
- Identify the phase conductor(s) to be metered — L for single-phase, L1/L2/L3 for three-phase.
- Open the split-core CT by unclipping the two halves at the hinge point.
- Position the CT around the phase conductor so the conductor passes through the CT aperture.
- Close the CT halves firmly until the latch clicks — ensure there is no gap between the two halves.
- Verify the CT arrow or polarity mark points in the direction of current flow toward the load.
- For EM-3P-60A, install a separate CT on each of the three phase conductors — L1, L2, and L3.
- Do not clamp the CT around both live and neutral conductors simultaneously — this results in zero reading.
- Plug the CT leads into the corresponding CT input terminals on the energy meter body.
DIN Rail Mounting & Power Wiring
Mount the energy meter on the 35 mm DIN rail in the electrical panel and connect the voltage sense and 12V DC supply wiring.
Steps
- Snap the energy meter onto the 35 mm DIN rail — press the top clip onto the rail then push the bottom in until it locks.
- Connect the voltage sense input: L to the meter's L (voltage) terminal for single-phase; L1, L2, L3 for three-phase.
- Connect Neutral (N) to the meter's N terminal for single-phase installations.
- Connect the 12V DC power supply: + to the meter's 12V input terminal, − to GND.
- Verify all terminal screws are tightened firmly — loose connections cause intermittent readings.
- Ensure the meter LCD powers on and displays voltage after the 12V supply is connected.
RS485 Wiring to Gateway
Connect the energy meter to the HPzenAi Gateway via shielded RS485 cable for communication and data upload.
Steps
- Run shielded RS485 twisted-pair cable from the energy meter to the HPzenAi Gateway.
- Connect the meter's RS485 A terminal to the gateway RS485 A terminal.
- Connect the meter's RS485 B terminal to the gateway RS485 B terminal.
- Connect the cable shield to earth at the gateway end only — do not earth both ends.
- If multiple meters share one RS485 bus, daisy-chain A-to-A and B-to-B between devices.
- Ensure each meter on the bus has a unique Modbus address (factory default is 1; adjust via meter DIP switches or configuration).
- For bus runs longer than 300 m, fit a 120 Ω termination resistor between A and B at the furthest meter.
Commissioning & Gateway Linking
After wiring, commission the meter by verifying live readings and linking the device to the HPzenAi app.
Steps
- Power on the panel supply and confirm the energy meter LCD shows live voltage and current readings.
- Open the HPzenAi app and navigate to Gateway → RS485 Scan.
- Wait for the scan to complete — the energy meter should appear with its Modbus address.
- Tap the detected meter and confirm Link to add it to your device list.
- Verify real-time power data (V, A, kW, PF) is displayed on the meter tile in the app.
- Apply a known load (switch on a pump or appliance) and confirm the app power reading increases accordingly.
- Configure alerts and cost rates: Meter → Settings → Energy Cost and Demand Alert.
Installation Checklist
Use this checklist before handing over the installation or proceeding to automation setup.
Steps
- Energy meter mounted securely on DIN rail.
- CT(s) clamped firmly around phase conductor(s) with no gap.
- CT polarity arrow pointing toward load (direction of current flow).
- CT leads plugged into correct meter input terminals.
- Voltage sense terminals connected — L (and N for single-phase).
- 12V DC supply connected and meter LCD active.
- RS485 A and B wired correctly to gateway — not swapped.
- Cable shield earthed at gateway end only.
- Unique Modbus address confirmed for each meter on the bus.
- Meter visible in HPzenAi app with live readings.
- Live load test confirms correct power readings.
- No exposed conductors or loose terminal screws.
Important Installation Notes
Follow these precautions during installation and service.
Steps
- All panel wiring must be performed by a qualified electrician in accordance with local electrical codes.
- Isolate the panel supply before making any voltage sense or power supply connections.
- CT installation around live conductors is permitted without isolating the load — exercise appropriate caution.
- Do not exceed the 60A CT rating — fit a larger CT and external meter for higher current applications.
- Keep RS485 signal cables separated from mains power cables to prevent interference.
- Replace CT leads if insulation is cracked or damaged — do not repair with tape.