Connecting Frame Ground - Panasonic KX-TA82492 - Voice Message Expansion Card Installation Manual

2.2 Installing the Advanced Hybrid System
2.2.5

Connecting Frame Ground

IMPORTANT
Connect the frame of the PBX to ground.
1.
Loosen the screw.
2.
Insert a grounding wire (user-supplied)*.
3.
Tighten the screw.
4.
Connect the grounding wire to ground.
* Use a grounding wire that has a conductor with a cross-sectional area of at least 0.75 mm
AWG. Green-and-yellow insulation is required.
• Be sure to comply with all applicable laws, regulations, and guidelines.
• Proper grounding is very important to protect the PBX from external noise and to reduce the risk
of electrocution in the event of a lightning strike.
• The AC cable's grounding pin may not be enough to protect the PBX from external noise and
lightning strikes. A permanent connection must be made between ground and the ground
terminal of the main unit.
In most of the continental United States, the ground provided by the "Third wire ground" at the
commercial power outlet will be satisfactory. However, in a small percentage of cases this ground may
be installed incorrectly. Therefore, the following test procedure should be performed.
Test Procedure
1.
Obtain a suitable voltmeter and set it for a possible reading of up to 250 V AC.
2.
Connect the meter probes between the 2 main AC voltage points on the wall outlet. The
reading obtained should be 108 V AC to 132 V AC.
3.
Move one of the meter probes to the 3rd prong terminal (GND).
Either the same reading or a reading of 0 volt should be obtained.
4.
If a reading of 0 volt at one terminal and a reading of 108 V AC to 132 V AC at the other
terminal is not obtained, the outlet is not properly grounded.
This condition should be corrected by a qualified electrician (per article 250 of the National
Electrical Code).
5.
If a reading of 0 volt at one terminal and a reading of 108 V AC to 132 V AC at the other
terminal is obtained, then set the meter to the "OHMS/RX1" scale, place one probe at the
GND Terminal and the other probe at the terminal which gave a reading of 0 volt.
A reading of less than 1 ohm should be obtained. If the reading is not obtained, the outlet is
not adequately grounded. See qualified electrician.
30 Installation Manual
Grounding Wire
To Ground
Screw
2
or 18