Tim Duckworth was nice enough to submit these pictures from when he installed his system. They are great to teach from:

Contact Placement:

When using traditional magnets ALWAYS place the sensor to the far left of right of the window. This is to ensure that magnet can be inserted vertically into the window and there is no chance of hitting glass. Tim used wide gap magnets which use a very small screw that could never penetrate far enough to damage the glass.

That is more than likely a 3/8" bit, depending on the contact size.

It is hard to tell from the photo but it is highly recommended to use clear silicone around the sensor when it is inserted into the hole.

Magnet Placement:

These are wide gap magnets. Installers like them because they are very small and there is little chance of damaging a window. Notice Tim took care not to damage the weather stripping.


Wire Termination:

Here you can see the white and green from the system attaching to the 2 reds from the contacts. Since this is new construction Tim has the luxury of terminating before sheetrock. The 2 pieces of heat shrink will slide up and protect the splice.

If this were a retrofit you would have to think about how wide the splice will be. If the splice is too wide it may not go back into a 3/8" hole. An offset splice (not shown) works well.