Siemens HiPath 3000 V3.0 or later Gigaset M1 Professional, Руководство по обслуживанию, Страница: 616 / 1202

Installing HiPath 3000
P31003-H3560-S403-54-7620, 09/05
4-138
HiPath 3000 V6.0, HiPath 5000 V6.0, Provisional Service Manual
inst_h3.fm
Installing HiPath 3750, HiPath 3700
Note on possible ground loops
4.3.4.6 Checking the Grounding
Procedure
Perform the tests in the table below to ensure that the system is properly grounded before star-
tup.
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To avoid ground loops from remotely operated devices (V.24 system peripherals),
the devices should be connected to the same low-voltage network (sub-distribution
board) if possible.
If the building floor plan does not permit this, you may need a line driver to isolate
the external devices in the event of a malfunction.
Step Activity Target
1. Check the ohmic resistance of the ground connection to
the 19-inch cabinet:
Perform measurement between the PE (protective
earth) on a socket in the internal installation (at the sys-
tem’s installation site) and HiPath 3700.
Prerequisites:
●
No device in the 19-inch cabinet is connected to the
low-voltage network via the power cable.
●
The system’s separate grounding (basic cabinet, ex-
pansion cabinet, patch panel) and the grounding of
the 19-inch cabinet are connected.
< 10 ohms
2. Check the ohmic resistance between the individual sys-
tem parts (basic cabinet, expansion cabinets, patch pan-
els).
Prerequisite:
HiPath 3700 is not yet connected to the low-voltage net-
work via the power cable.
< 1 ohm