5.1.2 MP-124 Rev. E
This section describes grounding and power surge protection for MP-124 Rev. E.
Warnings:
• The equipment must be installed only in telecommunication sites/ centers in
compliance with ETS 300-253 requirements “Earthing and Bonding of
Telecommunication Equipment in Telecommunication Centers”.
• Prior to installation, earth loop impedance test must be performed by a certified
electrician to ensure grounding suitability at the power outlet intended to feed the
unit. It is essential that the impedance will be kept below 0.5 ohms!
• Proper grounding is crucial to ensure the effectiveness of the lightning protection,
connect the unit permanently to ground as per the illustration in this section.
• MP-124 Rev. E includes an integrated secondary surge protection, but does not
include primary telecom protection. In order to comply with ITU-K.21 requirements
when the telephone lines are routed outside the building, it is essential to install
additional protection using a three-electrode Gas Discharge Tube (GDT) rated
350V as a primary protection on the MDF, located at the entrance point of
telephone wiring to the building. The center pin of the GDT must be connected to
ground as per the illustration in this section.
• Failing to install primary surge protectors, and failing to comply with the grounding
instructions or any other installation instructions, may cause permanent damage to
MP-124 Rev. E.
• As most of the installation is the responsibility of the customer, AudioCodes can
assume responsibility for damage only if the customer can establish that MP-124
Rev. E does not comply to the standards specified above (and MP-124 Rev. E is
within the hardware warranty period).
• The unit complies with protection levels as required by EN 55024/EN 300386.
Higher levels of surges may cause damage to the unit.
Lightning is the transient passage of electrical current between a cloud and the surface of
the earth. Part of the lightning current can be carried inside a building from electrical lines
and analog and/or digital telephone lines located outside. This direct injection of lightning
current inside a building can cause significant damage to electronic circuits and equipment.
MP-124 Rev. E must be installed in the Telecommunication rack. The MP-124 Rev. E
grounding screw must be connected to the equipotential grounding bus bar located in the
Telecommunication rack, using a wire of 6 mm
2
surface wire. This line must be connected
to the equipotential bus bar of the electrical circuit board located in the Telecommunication
room, using a stranded cable with surface area of 25 mm
2
. The length of this cable must
be as short as possible (no longer than 3 meters).
The MP-124 Rev. E chassis is equipped with a protective earthing screw. Ensure that you
connect this to the grounding point using a suitable wire. Fasten the cable securely using a
6-32 UNC screw.
The grounding and lightning protection cabling setup for MP-124 Rev. E depends on
whether AudioCodes orderable FXS Patch Panel (see Section 5.1.2.1) or a third-party MDF
(see Section 5.1.2.2) is used.
To Next Page
Loading...
