12 · EquipmentINTERMEDIATE
Environment equipment: exhaust fan, fan, humidifier
Everything that isn't the light or the pump goes here. Each device carries a role (what it is) and a mode (how it decides to turn on). With those two fields the system decides everything it does with the environment.
The roles
| Role | What it is |
|---|---|
| Light / Secondary light | The main lamp and the supporting ones. |
| Exhaust fan / Timed exhaust fan | Pulls air out. The "timed" one runs in fixed cycles without looking at the sensor. |
| Intake fan | Pushes air in. |
| Fan | Moves air inside. It doesn't change temperature or humidity by itself. |
| Humidifier / Dehumidifier | They raise or lower humidity. |
| Heater / Cooling | They raise or lower temperature. |
| CO₂ injector | You get the full CO₂ card, with a daily budget. |
| Pump / Valve | Irrigation: see the five modes. |
| Custom | Anything that doesn't fit: you turn it on and off yourself. |
The modes
| Mode | How it decides | When to use it |
|---|---|---|
| Manual | You turn it on and off from the card. | When you've just installed it and don't know what threshold you want yet. |
| Timer | Fixed loop: N minutes on, N off. | Air-exchange exhaust fans and circulation fans. |
| Follows the light | Turns on when the light turns on (or when it turns off, if you invert it). | Exhaust fans you only need with the lamp on. |
| By sensor | Turns on and off by a value from the zone's sensor, with hysteresis. | Everything that corrects the environment: humidifier, heater, cooling. |
The by-sensor rule, field by field
- Metric
- Temperature, humidity, VPD or CO₂.
- Turn-on value
- The number at which the equipment starts. The direction (greater than / less than) is not yours to pick: it comes from the role. A humidifier always turns on *below* a value and a dehumidifier always *above*.
- Hysteresis
- How many points the value has to come back for the equipment to stop. Without hysteresis the equipment turns on and off every minute and breaks.
- Night value
- A second threshold that only applies with the light off. The tent at night is a different tent: temperature drops and relative humidity rises without anything odd going on. Available on heater, cooling, exhaust fan, humidifier and dehumidifier, and only if the zone has a main light with a schedule — with no light there's no way to know when it's night.
- Per-stage presets
- The same equipment with different targets in veg, flower, drying and curing.
- Hysteresis floor
- The system won't let you set a gap smaller than 2 °C, 5 % humidity, 0.2 kPa of VPD or 100 ppm of CO₂. Below that the relay switches every few seconds with the sensor's noise, and that breaks the device and floods the cloud. The roles that run on a timer (timed exhaust fan, fan, intake fan) don't have this limit.
- Timer minimum
- In timer mode, each leg runs from 5 minutes to 24 hours.
- Safe mode
- What the equipment does if the sensor stops sending data: stay where it is, turn off or turn on. It's what keeps it from acting blind.
Do this
Always set hysteresis, even if it's just 2 points. A dehumidifier with no hysteresis does a hundred starts a night and dies in a month.
Avoid this
Don't put the circulation fan in by-sensor mode. It doesn't change the number you're measuring, so the rule is never satisfied and it stays on forever.
How urgent it is
EssentialThe right role on every device.
ImportantHysteresis and minimum times on everything that corrects the environment.
OptionalPer-stage presets and night value.