Karel DS200, Technical Reference And Installation Manual

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DS Series PBX Technical Reference And Installation Guide
119
XI.1.D.1.GROUNDING MEASUREMENT WITH THE MEGER
DEVICE
Two rods whose lengths are approximately 20-25 cm. three pieces of cables in three
different colors (yellow, red and green) and the measurement device with three input ports
are all included in the Meger grounding measurement device box. Colors of the inputs on the
measurement device are the same as that of the cables. After those cables are attached to
the inputs corresponding to their colors, the two rods are stuck into the ground at least 15-20
m. apart from each other. Then, the other end of the yellow cable is attached to one of the
rods, while the free end of the red cable is attached to the other rod. The green cable’s free
end is attached to the cable that extends toward the building to be connected to the
exchange. Finally, the largest resistance value on the device panel is selected, the test key is
pressed and held, and the grounding value is displayed on the screen. In case the value on
the display does not seem to make sense, the resistance value selected on the panel is
decreased and the measurement is repeated in order to obtain the actual grounding value.
XI.1.E. MAINS SUPPLY AND BATTERY
CONNECTIONS OF THE EXCHANGE:
The mains outlet where the exchange feed is to be received should be noise free as much as
possible and the 220 VAC output must be steady. If the output voltage keeps changing
and/or very frequent interruptions are taking place, then generator and/or regulator
connections might be needed in order for the exchange to operate properly. In this regard, it
is essential to find out the electricity supply regime in the area where the exchange is to be
installed.
Moreover, it would be useful to know about the expected traffic load while determining
capacity of the battery to be employed.
Similarly, another important point regarding the calculation of generator, regulator and
battery capacities, which would likely be used, is that if there are devices that ought to
operate whenever the exchange is operating and which are to be fed from the same source
as that of the exchange (such as maintenance computer, HDSL modems, etc.), then their
power consumptions are supposed to be recorded, so that they should be included in the
power consumption calculations.
THE POWER CONSUMPTION TABLE
Device Estimated power consumption
Exchange
PC
External Modem
HSDL Modem
List the other devices below.