AEMC instruments 275HVD, Руководство пользователя

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2
Non-Contact, High Voltage Detector 275HVD
After checking the 275HVD and ensuring its good operation, select the
test range. It is recommended to start with a lower setting than the actual
working voltage, and then to try again with higher settings. The user may
also consider using lower settings to check for lower voltages on a con-
ductor.
With the 275HVD at the end of a hot stick, move towards the live conduc-
tor until its warnings are triggered.
TEST
OFF
240V
2k
V
6k
V
11k
V
22kV
33 kV
13
2k V
27 5k
V
Hot Stick
4..5 Low Voltage Testing
See Warning on Page 5
The 275HVD Non-Contact High Voltage Detector works by proximity. The
275HVD is not designed to be in physical contact with live conductors. Its
sensor detects the radiated field that surrounds live conductors.
Do not touch live conductors with the 275HVD
Non-Contact High Voltage Detector.
Radiated field strength increases with voltage and decreases quickly with
distance and/or ground shielding. The radiated field from a cable where
conductors supplying three-phase power are close together, tends to
cancel out (See § 4.2). Detecting distance of a 250V
AC
single live wire
is about 4" (10cm). When grouped with neutral and ground wires, as in a
flexible cable, the distance is reduced to 2" (5cm) or less.