The rain rain sensor on the solar powered fresh air skylight seen here is the small gray box on the right side of the panel attached to the bottom of the skylight.
Velux skylight rain sensor problems.
A velux skylight installed with a velux flashing kit is guaranteed leak free for 10 years.
A deck mount skylight unlike a curb mount skylight is simply attached directly to the roof deck.
The skylight is then flashed sealed to become part of the roof.
Velux has a remedial option if a customer insists the skylight closes whenever it rains.
A wire extension can be ordered directly from velux to accommodate moving the sensor panel.
The rain sensors work when they get wet.
This particular type of rain sensor replaces an electric one because it would require too much continuous current to draw on the batteries in a solar charged system.
Based on the above we should expect to get paid for the installation that delivers what it promises.