Relay Controllers
Panel Installation
Mounting and power wiring for relay controllers.
Installation Video Guide
Tools Required
Gather these tools before starting. Power wiring involves 12V DC low-voltage connections; the AC power adapter wiring should be carried out by a qualified electrician.
Tool Checklist
| Preview | Quantity | Item | Details |
|---|---|---|---|
| × 1 | Flat-Head Screwdriver (3 mm) | For tightening DIN rail terminal block screws and relay output terminal screws | |
| × 1 | Flat-Head Screwdriver (5 mm) | For the AC power adapter input terminals if used with a DIN rail PSU | |
| × 1 | Wire Strippers | To prepare cable ends before insertion into terminal blocks | |
| × 1 | Multimeter | To verify 12V DC at the controller input before powering on | |
| As required | DIN Rail (35 mm) | Standard TS-35 DIN rail for mounting the controller in the panel | |
| × 4 | M4 Screws and Nuts | For direct panel mounting if not using a DIN rail | |
| As required | RS485 Shielded Cable (1 mm²) | Twisted-pair shielded cable for RS485 bus connection to the gateway | |
| As required | 2-Core Cable (1.5 mm²) | For relay output channel wiring to valves and loads |
Flat-Head Screwdriver (3 mm)
For tightening DIN rail terminal block screws and relay output terminal screws
Flat-Head Screwdriver (5 mm)
For the AC power adapter input terminals if used with a DIN rail PSU
Wire Strippers
To prepare cable ends before insertion into terminal blocks
Multimeter
To verify 12V DC at the controller input before powering on
DIN Rail (35 mm)
Standard TS-35 DIN rail for mounting the controller in the panel
M4 Screws and Nuts
For direct panel mounting if not using a DIN rail
RS485 Shielded Cable (1 mm²)
Twisted-pair shielded cable for RS485 bus connection to the gateway
2-Core Cable (1.5 mm²)
For relay output channel wiring to valves and loads
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 | Relay Controller Unit | Main controller board in IP40 enclosure — 8-channel relay outputs | |
| × 1 | DIN Rail Mounting Clip | Pre-fitted to the rear of the enclosure for 35 mm DIN rail installation | |
| × 1 | RS485 Terminal Block | 2-position screw terminal for RS485 A and B connection to gateway | |
| × 1 | Power Input Terminal Block | 2-position screw terminal for 12V DC positive and negative input | |
| × 1 | RF Antenna (XR1, XR3, X1, X3) | External whip antenna for RF radio — connect before powering on | |
| × 1 | Quick Installation Guide | Printed reference card covering mounting, power, RS485, and channel wiring |
Relay Controller Unit
Main controller board in IP40 enclosure — 8-channel relay outputs
DIN Rail Mounting Clip
Pre-fitted to the rear of the enclosure for 35 mm DIN rail installation
RS485 Terminal Block
2-position screw terminal for RS485 A and B connection to gateway
Power Input Terminal Block
2-position screw terminal for 12V DC positive and negative input
RF Antenna (XR1, XR3, X1, X3)
External whip antenna for RF radio — connect before powering on
Quick Installation Guide
Printed reference card covering mounting, power, RS485, and channel wiring
Mounting the Controller
The relay controller mounts on a standard 35 mm DIN rail inside a control panel or enclosure. For outdoor sites, install the controller inside an IP-rated weatherproof enclosure before mounting the DIN rail.
Steps
- Snap the controller onto the 35 mm DIN rail by pressing the bottom clip onto the rail and then pushing the top down until the clip locks.
- To remove from DIN rail, use a flat-head screwdriver to pull the bottom spring clip down, then tilt the unit off the rail.
- For direct panel mounting (without DIN rail), use four M4 screws through the rear mounting holes.
- Leave at least 50 mm clearance above and below the controller for cable routing and heat dissipation.
- For RF models (XR1, XR3, X1, X3), route the RF antenna cable out of the enclosure and mount the antenna in an unobstructed location.
- Install the enclosure at a height that allows easy visual inspection of the channel status LEDs during commissioning.
Power Wiring
The relay controller requires a 12V DC supply. Use an HPzenAi power adapter or a DIN rail mounted 12V PSU rated for the total load current of all relay channels combined.
Steps
- Use the HPzenAi PWR-1P-12V-15W power adapter for single-phase AC supply, or PWR-3P-12V-12W for three-phase supply.
- Wire the AC input side of the power adapter to the distribution board — this must be done by a qualified electrician.
- Connect the power adapter 12V DC positive output to the V+ terminal on the controller's power input block.
- Connect the power adapter 0V (negative) output to the V− terminal.
- Add a surge protection device (SPD-1P or SPD-3P) on the AC input to the power adapter to protect against lightning and surge.
- Tighten all terminal screws firmly — loose power connections cause intermittent behaviour and terminal overheating.
- Verify 12V DC at the controller input terminals with a multimeter before switching on.
Relay Output Channel Wiring
Each of the 8 relay channels has three terminals: COM (common), NO (normally open), and NC (normally closed). For standard valve and pump control, wire the load between COM and NO — the load energises when the relay is switched on.
Steps
- Run a 2-core cable from the controller channel to each field device (valve solenoid, motor starter control circuit, etc.).
- Strip 6–8 mm of insulation from each cable end.
- Connect one cable core to the COM terminal for the chosen channel.
- Connect the other cable core to the NO terminal for the same channel.
- For fail-safe configurations where the load must remain energised on power loss, connect to NC instead of NO.
- Tighten each terminal screw firmly — a loose output terminal is the most common cause of intermittent channel switching.
- Label each cable with the channel number and the load it controls.
Commissioning
After mounting and wiring, commission the controller by linking it to the HPzenAi app and testing each channel.
Steps
- Power on the controller and observe the status LED — it should flash blue (setup/pairing mode) or green (already configured).
- For RS485 mode: ensure the RS485 cable is connected to the gateway, then perform an RS485 scan from the app (Gateway → RS485 Scan).
- For Wi-Fi stand-alone mode: open the HPzenAi app → Devices → Add Device → Relay Controller and follow the Wi-Fi setup wizard.
- Once detected, the controller appears as a device tile in the app.
- Tap each channel in the app and use Manual Control to switch it on and off — verify the corresponding LED on the controller illuminates.
- With loads wired to each channel, verify each valve or device operates correctly from the app before creating any schedules.
- Assign a name to each channel in the app (e.g., 'Zone 1 — Drip Line') for easy identification.
Final Inspection Checklist
Steps
- Controller securely mounted on DIN rail or panel.
- RF antenna connected and positioned outside enclosure (RF models only).
- 12V DC power supply wired to V+ and V− input terminals.
- Surge protection device (SPD) fitted on AC input.
- RS485 A and B wired to gateway (RS485 mode) or Wi-Fi setup complete (stand-alone mode).
- All 8 output channel terminals wired and labelled.
- All terminal screws firmly tightened.
- Each channel tested from the app using Manual Control.
- All field devices (valves/motors) confirmed operating correctly per channel.
Important Installation Notes
Steps
- All relay output terminals are 12V DC — do not connect 230V AC loads to the relay controller output channels.
- Install the controller inside an IP54 or better weatherproof enclosure for any outdoor installation.
- Keep RS485 signal cables and relay output cables separated from 230V mains cabling to avoid interference.
- The 12V supply current must be sufficient for all channels operating simultaneously — budget 0.5A per solenoid valve channel.
- Do not exceed 5A per relay channel — check the rated current of each connected load before wiring.