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QUESTION 8b:
HOW IS THIS TEST DONE AND WHAT VALUE OF MEASUREMENT IS ACCEPTABLE?
ANSWER:
a) Set the instrument to be used on RESISTANCE (ohms).
b) Short the instrument test leads together (including any extension leads) and
make a note of the reading on the instrument.
c) To test, connect one test lead to the earth bar in the distribution panel and the
other test lead to the test point (each switch, socket outlet or other point of
consumption) and make a note of this reading (see Fig. B – Pg 3).
d) Subtract previous reading (b) from this reading (c) to get the required reading.
e) Compare this reading (d) with the maximum value given in table 1 above
(table 8.1 on page 276 of code of practice). SANS 10142
f) A reading lower than the listed value is acceptable.
g) All points must be tested.
h) The worst reading can then be recorded for each of the following:
lights, sockets, stove, geyser, etc. or all values measured can be written down as
illustrated in addendum A below.
QUESTION 9a:
WHAT INSTRUMENT CAN BE USED TO TEST THE CONTINUITY OF THE RING CIRCUIT?
ANSWER:
Any meter with continuity (buzzer) function similar to:
a) Toptronic TBM805
b) Toptronic T1151
c) Toptronic TBM811
d) Toptronic MacroG3
QUESTION 9b:
HOW IS THE TEST DONE AND WHAT VALUE OF MEASUREMENT IS ACCEPTABLE?
ANSWER:
a) Set the meter to the continuity function (no reading required).
b) Disconnect both ends of the ring from the circuit breaker. (refer Fig. C & D - Pg 5).
As this is an example only the phase conductor is shown).
c) Connect the test leads of the meter to the disconnected ends of the ring circuit.
(refer Fig. D)
d) If there is continuity the buzzer will sound.
e) Record the following onto the certificate: Correct or N/A.
f) Re-connect both ends of the conductors to the same terminal. Phases together
and neutrals together, etc. (refer Fig. D1)
QUESTION 10a: WHAT INSTRUMENT CAN BE USED TO TEST EARTH FAULT LOOP IMPEDANCE
(Main switch)?
ANSWER:
A digital earth loop tester like:
a) Toptronic T1125 (with electronic load).
Lights 10A (1.1
Ω
):
0.9
0.85
1.01
0.75
Sockets 20A (0.55
Ω
):
0.34
0.50
0.41
0.34
Geyser 40A (0.33
Ω
):
0.21
0.25
ADDENDUM A
Summary of Contents for ACADEMY T419
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