2-2-13
A 15-kilovolt-ampere transformer is checked and is carrying 19.5 kilovolt-amperes; it should be reported as overloaded. Select one: True False
True
A load test taken with a clip-on ammeter and a multimeter will indicate if a transformer is overloaded at the time of the test. Select one: True False
True
A single-phase transformer should have a maximeter placed on each secondary lead from the transformer. Select one: True False
True
Since a single-phase distribution transformer has two secondary coils, it is possible for only one coil to be overloaded. Select one: True False
True
The red indicator needle on a maximeter indicates the load at the time of the reading. Select one: True False
True
Overload peaks of ? do not affect a transformer. a.5 minutes b.10 minutes c.30 minutes d.60 minutes
A. 5 minutes
Maximeters record the ? during the time of the test. a.highest load b.highest voltage c.hours the line is energized d.normal current drawn off the transformer
A. Highest load
A 15-kVA single-phase distribution transformer shows 75 amperes on X1 and 60 amperes on X3. Voltage is 120 volts from each secondary bushing to the neutral. The transformer has exactly ? of load. a.10.6 kVA b.16.2 kVA c.19.2 kVA d.22.5 kVA
B. 16.2 kVA
An engineer wants an accurate spot load check on a single-phase service. The A conductor has 115 volts and 95 amperes, and the B conductor has 113 volts at 78 amperes. There is ? being pulled off the transformer. a.15.6 kVA b.19.7 kVA c.25 kVA d.33.5 kVA
B. 19.7 kVA
The tap setting on the side of the maximeter should be set to ? if placed on a 25-kVA single-phase transformer. a.20/1 b.40/1 c.100/1 d.the highest scale
B. 40/1
When a maximeter is clamped around an energized conductor, never ? . a.bump the meter b.change taps on the meter c.tape the meter in place d.turn the meter with the dial up
B. Change taps on the meter
According to the rule of thumb in the reference book, at 120 volts single-phase, there are ? available from a 25-kilovolt-ampere transformer. a.110 A b.115.6 A c.207.5 A d.244.6 A
C. 207.5 A
Total phase current times line to neutral voltage equals kilovolt-ampere. Select one: True False
False
Twenty- to thirty-minute overload peaks are of no concern when conducting a load test. Select one: True False
False
A balanced load on a transformer is when ? . a.both phase to neutral leads have the same load b.both phase to neutral leads have the same voltage c.the kVA of the transformer is at its maximum d.the kVA of the transformer is not reached
a.both phase to neutral leads have the same load
