Megger BTDR1500 Guia Del Usuario página 13

C
AU TO TEST
B
→ I N SULA TIO N TEST ←
A
LO OP TEST
FAU LT FI ND I NG
E
Tes t i ngi nsul at i on- pl ease wa i t
The result of the insulation test is then displayed as an insulation resistance (Re) – see the
bridge specification for the measurement resolution and increments.
If Re <1 MΩ - LINE IS BAD If 1 MΩ <Re <10 MΩ- LINE IS FAIR If Re >10 MΩ - LINE IS GOOD
NOTE: If the insulation resistance >20 MΩ, then the instrument can not locate the fault during
the fault finding test.
7.2.2. Auto test – Loop
By pressing the Up / Down Gain key to proceed (#7, table1) the test sequence then switches
to the loop test where a 2 or 3-wire test for both the loop test and the fault finding can be
selected. See section 7.1 for connection requirements. For the 2-wire testing method, the
measurement is of the total loop resistance and the RTS is assumed half of that resistance.
For the 3-wire testing method, the two good wires allow for the resistance of the faulty wire
(RTF + STF) to be measured directly and so no such assumptions are made. The use of the
3-wire test method is strongly recommended.
LINE IS GO O D
^200. 0M Ω
100
Pr ess t o p roce ed
AU TO TEST SE QUE N CE:
I N SULATIO N TEST
2 -W I RE
→ LO OP TEST ←
Pr es s M ENU t o sel ec t
FAU LT FI N D I NG
Pr ess to p r oceed
With the loop test, the auto sequence is used to verify that any loop resistances are < 2 kΩ.
This is the A-B loop only on the 2-wire test and A-B and A-C loops on the 3-wire test.
If this is not the case then an error message: A – (B/C) STRAP OPEN OR LINE TOO LONG
is displayed. You will then be prompted to return to the Bridge Menu.
NOTE – the loop resistance result is not given as the fault finding test will use the result to
derive its readings.
When the type of test is selected,
again the screen will indicate
between which terminals the loop
3 -W I RE EXI T
resistance is measured. Alternatively,
pressing EXIT will return you to the
Bridge Menu.
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