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2.3
Testing Procedures and Safety Precautions: For Guidance Only
THE PROCEDURES SET OUT BELOW MUST ONLY BE CARRIED
OUT BY AUTHORISED PERSONNEL.
Local Health and Safety Regulations Must Be Observed.
2.3.1
SAFETY PRECAUTIONS:
a.
Always ensure by means of a live line tester that the cable about to be tested is
not live. This applies both to old and newly installed cables and also to all phases.
b.
The test area must be well signed
"" DANGER H.V. TESTING ""
, or similar
wording at both ends of the cable.
c.
The test area at each end of the cable must be roped off.
d.
It is important for the safety of the operator and to protect the equipment that
an adequate ground connection be provided. The ground is normally connected
to the cable sheath. If the cable sheath is not earthed (this may occur on cables
which have just been installed) a temporary earth spike 0.5M long may be used.
However, this should be treated with caution, since the soil may have a high
resistivity
2.3.2
CONNECTION SEQUENCE:
(See Figure 1.1 for UNI-POLAR and Figure 1.2 for BI-POLAR testing)
a.
Connect earth lead between test object earth and PT30-10 earth terminal.
b.
Connect discharge/earthing probe to the PT30-10 earth terminal. The earth
hook on the probe must now be placed on the test object terminal.
c.
Connect the phases not being tested to earth. This means 1 phase for bi-
polar test and 2 phases for a unipolar test.
d.
For a unipolar test connect the black/negative HV lead to the negative out-
put socket on the PT30-10 and the test object. The positive output must be
blanked off using the bung provided.
e.
For a bipolar test proceed as 2d but connect the red/positive HV lead to the
positive output socket on the PT30-10 and the test object.
f.
Ensure The Correct Supply Voltage Is Selected On The
PT30-10.
g.
Connect the PT30-10 to mains supply.
h.
Repeat The Procedure And Check That All Connections Are Secure
And That All Unauthorised Personnel Are Out Of The Test Area.
i.
Remove the discharge/earthing probe
