Megger TDR1000/2 Guide De L'utilisateur page 15

Operation
Except where otherwise stated, this specification
applies at an ambient temperature of 20 ºC.
General
Ranges:10 m, 30 m, 100 m, 300 m, 1000 m,
3000m (30 ft, 100 ft, 300 ft, 1000 ft, 3000 ft,
10000 ft)
Accuracy: 1% of range pixel at 0.67 VF
[Note- The measurement accuracy is for the
indicated cursor position only and is conditional
on the velocity factor being correct.]
Resolution: 1% of range.
Input Protection: This instrument complies
with IEC61010-1 for connection to live systems up
to 300V CAT III. Fused leads must be used if the
voltage between the terminals exceeds 300V.
Output pulse: 5 volts peak to peak into open
circuit. Pulse widths determined by range and
cable impedance:
25Ω 50Ω
10m
7ns 7ns
30m 20ns 20ns
100m 100ns 60ns
300m
300ns 120ns
1000m 1000ns 520ns
3000m 3000ns 2020ns
Gain: Set for each range with four
user selectable steps.
Velocity Factor: Variable from 0.20 to 0.99 in
steps of 0.01
Impedance matching: 25, 50, 75, 100
Tx Null (where fitted): 0 to 120
Refresh Rate: Selectable from the menu.Once
per second or three times a
second.
Power Down: Automatic after 5 minutes with
no key press.
Backlight: Stays on for 1 minute when
activated.
75Ω 100Ω
7ns 7ns
20ns 20ns
100ns 100ns
170ns 300ns
680ns 1000ns
2340ns 3000ns
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