Dahua Smart Box Series, User Manual

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Standalone DVR User’s Manual
347
The thunder proof ground shall adopt the special ground cable from the monitor
control room to the ground object. The ground cable adopts copper insulation cable
or wire and its ground section shall be more than 20mm2.
The ground cable of the monitor system can not short circuit or mixed connected with
the strong alternative current cable.
For all the ground cables from the control room to the monitor system or ground cable
of other monitor devices, please use the copper resistance soft cable and its section
shall be more than 4mm2.
The monitor system usually can adopt the one-point ground.
Please connect the ground end of 3-pin socket in the monitor system to the ground
port of the system (protection ground cable)
4. The shortcut way to check the electric system using the digital multimeter
For 220V AC socket, from the top to the bottom, E (ground cable), N (neutral cable), L(live
cable). Please refer to the following figure.
There is a shortcut way to check these thee cables connection are standard or not (not the
accurate check).
Importance
In the following operations, the multimeter range shall be at 750V!
For E (earth cable)
Turn the digital multimeter to 750V AC, use your one hand to hold the metal end, and then
the other hand insert the pen to the E port of the socket. See the following figure. If the
multimeter shows 0, then you can see current earth cable connection is standard. If the
value is more than 10, then you can see there is inductive current and the earth cable
connection is not proper.