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Hardware Installation
4 Andover Controls Corporation
The cable should have a nominal impedance of 100 Ohms and a nomi-
nal velocity of propagation of 78%.
Capacitance of Infinet cable should be nominal, below 12.5 pF/ft
(41pF/m) between conductors and below 22 pF/ft (72 pF/m) between
the conductor connected to ground and the next conductor.
Lightning Protection
Lightning Arrestors are required at each point where an Infinet or other
wiring (such as for a card reader) enters or exits a building. Use the
following arrestor: Two pair combination gas tube/silicon avalanche ar-
restor, Andover Controls # 01-2100-299.
Building Ground Requirements
Warning
Be sure that all Infinity products from Andover Controls Corporation
are 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
Grounding should be in accordance with article 240 of the National
Electrical Code. 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.
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