A E1/T1 Grounding Criteria - Huawei TE40 Administrator's Manual

HUAWEI TE40&TE50&TE60 Videoconferencing
Endpoint
Administrator Guide
Read the following grounding criteria carefully and comply with the relevant requirements
during the installation of the endpoint.
The grounding design of the telecom office (station) follows the principle of equalized voltage.
That is, the work grounding and the protection grounding (including the shielded grounding
and the surge protection grounding of the distribution frame) share a set of grounding
conductors.
When the E1 cable of the cabinet is over 7.5 m and the T1 cable of the cabinet is over 10 m, a
shielded cable and a shielded connector should be used and grounded.
When the E1 interface is connected to other devices using coaxial cables, the external shield
layers at the transmitting endpoint and receiving endpoint should be connected to the
protection ground at the same time. The dual in-line package (DIP) switch offers the possible
disconnection function at the receiving end.
Copper-core materials instead of aluminum materials should be used for the ground cable.
The plastic insulated copper wires with yellow and green insulation color should be used for
the protective ground cable. The protective ground cable should not exceed 30 m, and the
shorter the better. When the protective ground cable exceeds 30 m, the ground bar should be
rearranged.
In a balanced circuit, the joint of the E1 (T1) cable and the connector should be grounded
using the external shield layer (the grounding conductor) or an additional wire to ensure
normal reception and transmission in each E1 (T1) channel. In an unbalanced circuit, the
metal braid shield layer of the cable should be seamlessly connected to the coaxial connector.
When the E1 cable exceeds 30 m and the T1 cable exceeds 40 m, use the multi-point
grounding mode. In addition, connect the E1 cable to the ground at every 15 m and the T1
cable to the ground at every 20 m.
When the E1 or T1 cable is extended out of the office (station), the E1 or T1 cable should go
through the main distribution frame (MDF) attached with the security unit. The shield layer of
the E1 or T1 cable should be firmly connected to the protection ground of the MDF. The
security unit on the MDF should have the overvoltage protection, overcurrent protection, and
failure alarm functions. The maintenance personnel should check the equipment periodically
and replace the ineffective protection unit in time.
For questions about grounding the device, contact the device provider for technical support.
Issue 01 (2013-09-30)
A
E1/T1 Grounding Criteria
Huawei Proprietary and Confidential
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A E1/T1 Grounding Criteria

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