Installation and wiring
Mechanical mounting, the mains connection, and a terminal-by-terminal wiring table for every connector on the board.
This page covers mechanical mounting, the mains connection, and a terminal-by-terminal wiring table for every connector on the board.
Mounting
- Fix the board in a dry enclosure with the terminal blocks facing the cable entries.
- The board has five mounting holes (
H1–H5). - Keep the controller electronics away from condensation and from the humidified air stream.
- Leave room below the terminal blocks for the cables to bend.
Power supply
The board has no separate low-voltage supply input. It is powered from mains, and it derives its own 24 V DC rail internally.
Warning
J2 (Mains) carries mains voltage. The mains rail is also present on the valve
terminals and on the motor terminal. Work on these terminals only with the power
disconnected, and earth the board as shown below.
Mains input — J2 (Mains)
A 3-pole terminal block (Wago 2604-1103). Each pole has two wire holes.
| Pin | Function | Notes |
|---|---|---|
| 1–2 | Neutral | Connected internally to the mains neutral rail and to the motor terminal J33 |
| 3–4 | Line | Feeds the internal 24 V supply and the mains rail used by the valve and motor relays |
| 5–6 | Earth | Chassis earth; also brought out to every mains valve terminal and to J33 |
The Earth terminal is not bonded to the controller's signal ground anywhere in the
design. Mounting holes H1 and H2 are on Earth; H3, H4 and H5 are on the signal
ground. Do not use the earth terminal as a signal reference.
Internal rails
The following rails exist inside the board. They are listed here because some terminals expose them.
| Rail | Where it comes from | Where it appears |
|---|---|---|
| 24 V DC | Mains-fed 24 V module on the board, rated 24 V / 1.3 A | J12, J14, J16, J18, J19, J7 (pin 1 and 3) |
| 5 V DC | Regulator on the board | J5 (pins 1–3) |
| 24 V DC, isolated | Isolated 24 V converter | J9 (pin 1), J11 (pin 1) |
| 5 V DC, isolated | Isolated 5 V converter | J34 (pin 1), J35 (pin 1) |
Wiring diagram — mains group
Wiring table — mains valve outputs
Five terminals switch mains to the atomisation valves. Every one of them has the same three-pin layout.
| Terminal | Schematic name | Pin 1–2 | Pin 3–4 | Pin 5–6 |
|---|---|---|---|---|
J28 | Klep1 | Switched leg (closed to neutral when the output is on) | Line | Earth |
J25 | Klep2 | Switched leg | Line | Earth |
J26 | Klep3 | Switched leg | Line | Earth |
J27 | Klep4 | Switched leg | Line | Earth |
J31 | Klep5 | Switched leg | Line | Earth |
Each valve is wired between the switched leg (pin 1–2) and the line (pin 3–4). The output is off when the relay is open. The earth pin is for the valve's earth or shield connection.
The current firmware drives Klep1, Klep2, Klep3 and Klep4 as the four atomisation
valves, and Klep5 as the flush drain valve.
Warning
These terminals switch mains. The valve coil sits between the switched leg and the line, so the full mains voltage is present across the valve whenever the output is off. Isolate the mains before working on a valve.
Wiring table — motor output
| Terminal | Schematic name | Pin 1–2 | Pin 3–4 | Pin 5–6 |
|---|---|---|---|---|
J33 | Motor | Neutral | Switched line | Earth |
The line side is switched, so the motor is only live when the controller turns it on.
Wiring table — 24 V relay outputs
Four potential-free (dry) relay contacts. The board applies no voltage to these terminals; they only switch whatever you wire into them.
| Terminal | Schematic name | Output | Pins |
|---|---|---|---|
J21 | Status | Status relay | 1–2 |
J22 | Alarm | Alarm relay | 1–2 |
J23 | AUX1 | Auxiliary 1 relay | 1–2 |
J24 | AUX2 | Auxiliary 2 relay | 1–2 |
Each of these relays switches one contact. Which way the contact sits when the output is
idle is decided by which of the two terminals you connect to; the software setting
(Status output mode, Alarm output mode, Aux 1 contact mode, Aux 2 contact mode)
decides whether the relay is energised when the output is active or when it is idle. See
Settings reference.
AUX1 and AUX2 are also driven by an alarm mask: an auxiliary output is active whenever
any alarm in its mask is active.
Wiring table — 24 V digital inputs
All five of these inputs are isolated from the controller electronics by an optocoupler and are read as active when 24 V is present.
| Terminal | Schematic name | Function | Pin 1 | Pin 2 | Link |
|---|---|---|---|---|---|
J12 | MEn | Master enable | +24 V | Signal | J13 (JP3) |
J16 | HL_ONOFF | Hygrostat | +24 V | Signal | J17 (JP1) |
J14 | Airflow | Airflow | +24 V | Signal | J15 (JP2) |
J18 | Flush | Opens the flush drain valve | +24 V | Signal | none |
J19 | TempMotor | Motor overtemperature | +24 V | Signal | J20 (JP1) |
Fitting the link next to an input forces that input permanently active. It is there so a technician can hold an input active without cutting the field cable and placing a bridge. Remove the link for normal operation. See Hardware reference.
Each link sits next to the input it holds high, so you can tell them apart by position.
Wiring table — water leak input
| Terminal | Schematic name | Pin 1 | Pin 2 | Pin 3 | Pin 4 | Link |
|---|---|---|---|---|---|---|
J7 | Waterlek | +24 V | 0 V | +24 V | Signal | J8 (JP2) |
The terminal offers both a 24 V and a 0 V feed, so a two-wire leak detector can be wired directly. The signal pin behaves like the other 24 V inputs: the leak alarm is raised when 24 V is present on pin 4. The alarm stays raised until you reset it; it never clears on its own.
Wiring table — analogue inputs
| Terminal | Schematic name | Pins | Function |
|---|---|---|---|
J11 | Demand_IN | 1: +24 V (isolated) · 2: signal · 3: 0 V (isolated) | Demand input. 0–10 V or 4–20 mA, selected by the Demand input mode setting |
J9 | HR Transmitter | 1: +24 V (isolated) · 2: 4–20 mA signal | Return-air humidity transmitter. The board powers the transmitter from pin 1 |
J34 | VD | 1: +5 V (isolated) · 2: 0 V (isolated) · 3: signal | Inlet pressure, 0–10 V, measured before the pump |
J35 | HD | 1: +5 V (isolated) · 2: 0 V (isolated) · 3: signal | Pump pressure, 0–10 V, measured after the pump |
The demand input is loop-powered from the board: the transmitter is supplied from pin 1 and returns its signal on pin 2.
Wiring table — analogue output
| Terminal | Schematic name | Pins | Function |
|---|---|---|---|
J36 | unnamed in the schematic | 1–2 | 4–20 mA output |
What the output carries is set by Analog output. The output is scaled over the full
4–20 mA range; pressure signals are scaled over 0–20 bar.
Warning
The 4–20 mA output is a two-wire loop. The controller does not power it: the
transmitter takes its supply from the loop itself. You must fit an external supply
(typically 24 V) across J36 pin 1 and pin 2 for the output to produce a current.
Wiring table — sensors and probes
| Terminal | Schematic name | Pins | Function |
|---|---|---|---|
J10 | Pulse_WC | 1: +5 V · 2: pulse signal · 3: 0 V | Water-flow sensor (pulse output) |
J37 | unnamed in the schematic | 1: Yx-1 · 2–4: electrode · 3: temperature · 5: 0 V (isolated) | Conductivity probe: two electrodes and a temperature sensor |
Wiring table — communication ports
| Terminal | Schematic name | Pins | Function |
|---|---|---|---|
J4 | RJHSEN384 | 8P8C | Ethernet. Link and activity LEDs are built into the connector |
J6 | unnamed in the schematic | 1: 0 V · 2: Mod- · 3: Mod+ | Fieldbus RS-485 |
J5 | 8P8C | 1–3: +5 V · 4–5: Scr-/Scr+ (RS-485) · 6–8: 0 V | Screen connection |
J32 | GT-USB-7055BB | USB-C | Service connection: Modbus, and the firmware update connection |
The fieldbus and screen RS-485 links are separate buses with separate transceiver circuits. Do not join them together.
The screen bus is a point-to-point link with only one device on it. The fieldbus is a multi-drop bus. See Connectivity.
Wiring order
- Wire all low-voltage signals first: analogue inputs, digital inputs, sensors, fieldbus, Ethernet, screen, USB.
- Wire the 24 V relay outputs.
- With the mains still off, wire the mains valve terminals and the motor terminal.
- Connect the mains at
J2last. - Power on and check the
5VLED.
Next steps
- Hardware reference — pinouts, link positions and electrical specifications.
- Connectivity — network and fieldbus setup.
- Troubleshooting — if something does not come up.