CAPTAIN 8 CP2P Ventilation Controller – Setup & User Guide
Wiring examples and setup parameters for pairing the AutoVent CAPTAIN 8 controller with the CP-2P contactor box to run fans, shutters, and heaters.
About this guide
This guide covers wiring examples for the AutoVent CAPTAIN 8 controller used with the CP-2P contactor box. The CP-2P lets the controller’s low-voltage relay outputs switch higher-voltage fans, shutters, and heaters through external contactors. Each example shows the wiring and the matching setup parameters (P-numbers) you enter in the controller’s setup menu.
The CP-2P contactor box
The CP-2P is a contactor box that sits between the CAPTAIN 8 controller and your line-voltage equipment. The controller’s relay outputs feed the box’s common control inputs, and the box’s contactors switch the load. A single CP-2P houses two contactors (contactor #1 and contactor #2).
Each relay terminal on the box is marked with its contact type:
C – Normally closed
B – Common
2 zones cooling: Captain8 to CP-2P
This example wires the CAPTAIN 8 relay board into one CP-2P box to run two cooling zones (two fans). It shows both a 240v example and a 120v example feeding the contactors from the breaker panel.
- 240v example: L1 and L2 in; L1 Switched and L2 switched out to the fans.
- 120v example: Hot and Neutral in; Switched hot out to the fan.
3 rollups, 1 cooling, and 1 heater pinout
This pinout runs three rollup vents, one cooling output, and one heater. The busbar is extended to #7 on the top row, and each relay is rated for a maximum of 7.5 amps. A jumper makes the fans and shutters operate as a single unit, so they all operate as Fan #1.
| ID | Description | Value |
|---|---|---|
| P0 | Number of Vent circuits | 3 * |
| P1 | Vent starting relay | 1 |
| P2 | Number of Fan / cooling circuits | 1 |
| P3 | Fan starting relay | 7 |
| P4 | Number of heating control circuits | 1 |
| P5 | Fan starting relay | 8 |
| P6 | Number of Lighting control circuits | 0 |
| P8 | Number of Light dep motors | 0 |
| P10 | Number of Dehumidifier circuits | 0 |
2 rollups and 2 heaters pinout (120/240)
This pinout runs two rollup vents and two heaters, with two separate cooling zones. Fan #1 zone and Fan #2 zone are each driven by a contactor in the CP-2P box. A contactor box is needed for the fans.
| ID | Description | Value |
|---|---|---|
| P0 | Number of Vent circuits | 2 * |
| P1 | Vent starting relay | 1 |
| P2 | Number of Fan / cooling circuits | 2 |
| P3 | Fan starting relay | 7 |
| P4 | Number of heating control circuits | 0 |
| P5 | Fan starting relay | 9 |
| P6 | Number of Lighting control circuits | 0 |
| P8 | Number of Light dep motors | 0 |
| P10 | Number of Dehumidifier circuits | 0 |
Shutters: working together or not
Shutters can be wired so they activate together with the fan, or so the windows and fans work independently.
Shutters and fans working together
Sometimes the shutters are connected to the fans. When the fan turns on, the shutters open too. They always work together. The shutters won’t open unless the fan is running. This way is easier for the controller, like it’s using less brain power. But in small greenhouses, the temperature might swing quickly.
- Only 1 relay used.
- Only 1 contactor.
Windows and fans separate
Sometimes the windows and fans can work by themselves. This gives us an extra way to cool down the greenhouse.
- Uses 2 relays.
- Uses 2 contactors.
Windows open before fans
We can also make the windows open a little bit before the fans turn on. This can help keep the temperature more steady. It’s like opening a door to let in some fresh air before turning on a big fan. But this trick doesn’t work well in long greenhouses. The air near the shutter might get too cold.