Prostat SureTest PGT-61-154, Руководство по эксплуатации

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PGT-61-154 SureTest Circuit Analyzer
9
Voltage Drop at 20-Amp load
The National Electrical Code recommends 5% as the maximum voltage drop
for branch circuits for reasonable efficiency (NEC article 210-19. FPN 4).
High voltage drop could be an indication of a high resistance connection
within the circuit, undersized wire for the load or length or run, or a defective
device on the branch circuit.
All of the voltage drop measurements are taken under an actual 12-Amp
load and extrapolated for 15 amp and 20 amp measurements. This allows
the user to test a 15-amp rated circuit at full capacity or 80% capacity, and
test a 20-amp rated circuit under a full capacity. Voltage drop under a 15-
amp load is the first measurement within this menu selection. Pressing the
side arrow button (
→
) moves the unit from measurement to measurement
within the line voltage menu. Pressing the down arrow button (
↓
) moves the
unit to the next menu selection – Ground-Neutral Voltage.
Troubleshooting Tips
Measurement Expected
Result
Problem Possible
Causes
Possible
Solutions
Voltage Drop < 5% High voltage
drop
•
Too much
load on the
branch circuit
•
Undersized
wire for
length of run
•
High
resistance
connection
within the
circuit or at
the panel
•
Redistribute
the load on
the circuit
•
Check code
requirements
and re-wire if
necessary
•
Locate high
resistance
connection/de
vice and
repair/replace
G. Ground-Neutral Voltage Measurement
There is only one test within the Ground-Neutral Voltage menu. In a single-
phase circuit, high ground-neutral voltage indicates excessive leakage
between the neutral and ground conductors. In a 3-phase circuit with a
shared neutral, a high ground-neutral voltage could also indicate unbalanced
load between the three phases, or harmonic distortion on the shred neutral. A
reading of less than 2 volts usually indicates a usable outlet. An excessive