Introduction - Megger TDR1000/2 Guide De L'utilisateur

Introduction

of at least two insulated metallic elements, one of
which may be the armouring or screen of the cable.
The TDR1000/2 has internal matching networks to
allow testing of 25, 50, 75 and 100 cables. (These
typically correspond to power, coaxial data and
data/telecoms cable). By selecting the TDR
impedance closest to that of the cable under test,
maximum power can be transmitted into the cable
allowing long cables to be tested.
The velocity factor of the TDR must be adjusted to
match that of the cable under test, allowing an
accurate distance measurement to be read directly
from the instrument. Where the VF of a cable is not
known, but the length is, the cursor can be set to the
end of the cable and the VF on the TDR adjusted until
the correct cable length is displayed.
Other configuration settings include changing the
distance units between metres and feet, changing the
propagation velocity units between a ratio and a
distance per microsecond. Display contrast is fully
adjustable to compensate for all viewing conditions.
A backlight aids viewing in low ambient light
conditions.
The instrument can be powered by manganese-
alkali, nickel-cadmium or nickel-metal-hydride
batteries. All cells must be of the same type.
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