LCX 890 Installation Guide 5
Building Ground Requirements
Warning
Be sure that all hardware from Andover Controls Corporation is
grounded to true earth ground. This kind of ground protects the
equipment from transients and other power surges in the area.
We cannot guarantee that the controller system will operate as
documented unless you properly ground all controllers.
Warning
Be sure to have your grounds inspected before you begin the
installation process to be sure your municipality follows the National
Electrical Code. Many municipalities do not and often have
substandard electrical grounds.
An example of a substandard ground is a galvanized steel cold water
pipe. As the pipe corrodes, it does not act as a true ground. The corro-
sion acts as an insulator, raising the potential of the pipe with respect to
the ground.
When lightning strikes in the area of the installation, it drastically
changes the potential of the earth. Since properly grounded Andover
Controls units respond to changes in potential more rapidly than poorly
grounded electrical systems, a poorly grounded building tries to reach
ground through the Andover Controls system. The surge of current can
destroy electronic components on the controller board.
Surges of much lower potential than lightning also impact the reliability
of Andover Controls equipment.