Megger TDR2050 User manual

3. CONNECTION
For best performance ensure that the
test leads are not unduly separated
Only use Megger approved fused
test leads
Ensure that the test leads are in good
condition and working order
TDR2050 Quick Start Guide
2. SELECT TEST MODE
a. Press to select
Hold
TDR2050
OK
Hold
TDR2050
OK
1. POWER UP
Press and hold to turn TDR on
Hold
TDR2050
OK
c. Press OK key to select
b. Use cursor keys to select test mode
required - choose T1

4. SELECT PARAMETERS
a. Press spanner/setting symbol
c. Set cable impedance
If the impedance is unknown, set to max using
the
arrows. Press when set.
b. Set correct velocity factor
(obtained from cable manufacturer) for the cable
to be tested. If unknown, see last page for
examples. Adjust using the UP DOWN arrows.
Press when set.
d. Set gain
Set to a level which best shows by toggling
the gain using trace arrows. Press when set.
Hold
TDR2050
OK
VF = 0.54R Z = 140 = 6 = 40ns 100m
AUTO MAN
f. Cable distance
Adjust to a distance greater than the known
cable length.
e. Set output pulse width
Set at mid point and toggle up / down until fault
becomes clear. Press when set.
Set at low pulse width for near end faults. Set at high pulse
width for distant faults and concentric cables.
Hold
TDR2050
OK
VF = 0.54R Z = 140 = 6 = 40ns 100m
AUTO MAN
Hold
TDR2050
OK
VF = 0.54R Z = 140 = 6 = 40ns 100m
AUTO MAN
Hold
TDR2050
OK
VF = 0.54R Z = 140 = 6 = 40ns 100m
AUTO MAN
Hold
TDR2050
OK
VF = 0.54R Z = 140 = 6 = 40ns 100m
AUTO MAN
IMPORTANT:
Ensure you are on manual mode.
AUTO MAN

5. MOVING CURSOR
Hold
TDR2050
OK
C1-C2
To select cursors press a. Cursor choice. b. Swap between cursors. Press C1 - C2
buttons to select cursor to move.
c. Use left/right arrows to move d. Cursor position on trace. Move cursor e. Delta measurement. TDR shows total
selected cursor. C1 to end of test leads about 1.5 m. distance to cursor C2 and difference
Move C2 to the end of the cable between C1 and C2.
(first significant reflection)

8. TYPICAL VELOCITY FACTORS
These values of velocity factor are typical and may be used in the
absence of known values of cables.
These values may need changing after verifying on a specific cable.
Five output impedances are available (25, 50, 75, 100, 140 ohms) and
an auto impedance matching feature. The velocity factor can be set
between 0.2 and 0.99 to meet any cable test requirements.
Material Cross section
mm2V. F m/μS m/uS
XLPE 35 0.52 156 78
XLPE 50 0.52 156 78
XLPE 70 0.53 160 80
XLPE 95 0.53 160 80
XLPE 185 0.55 165 81.5
XLPE 240 0.56 168 82
XLPE 300 0.56 170 82
XLPE 500 0.56 173 82.5
XLPE 630 0.57 173 82.5
PILC 70 0.52 156 78
PILC 185 0.52 156 78.5
PILC 240 0.53 156 79
PILC 300 0.55 165 80
PILC 0.1 in20.52 156 78
PILC 0.3 in20.52 156 78.5
PILC 0.4 in20.53 156 79
PILC 0.5 in20.55 165 80
Megger Instruments Limited, Archcliffe Road, Dover, Kent, CT17 9EN, England
T [phone] F [phone]
Part No. 1005-021
Megger is a registered trademark
TDR2050_QS_EN_V01
Printed in England www.megger.com
This instrument is manufactured in the United Kingdom. The company reserves the right to change the specification or design without prior notice.