The CaterpillarR automates dome functions via four relays, wired in parallel with the existing buttons on the control unit. Each relay output corresponds to one button:
| CW | Clockwise dome rotation |
| CCW | Counter-clockwise dome rotation |
| Open | Shutter / flap open |
| Close | Shutter / flap close |
The relay acts as a dry contact (equivalent to pressing the button), so no additional power supply is needed from the CaterpillarR side. End-of-travel detection comes from the existing motor system, just as with manual button operation.
If your dome's shutter has flaps (AKA lower shutters) as a distinct element from the main opening, see Flaps (lower shutters) for how they are handled on this model.
Identify your existing control panel's button terminals with a multimeter before connecting. Verify that the button contacts are isolated from mains voltage, the CaterpillarR relays are rated for low-voltage control signals only.
Need: connector type and pin numbering on the CaterpillarR board, relay specs (max switching voltage and current).