2-2-12
A(n) ? installed in series with a fuse cutout can protect a worker when energizing a defective transformer. a.animal protective shield b.current-limiting fuse c.fuse enclosure d.lightning arrestor
B. Current limiting fuse
A short-circuited secondary, an overload, or a(n) ? current are the usual causes for a transformer to overheat. a.applied b.follow-through c.induced d.leakage
B. Follow through
A neutral is a grounded conductor while a ground wire is a(n) ? conductor. a.bonding b.grounding c.insulating d.isolating
B. Grounding
One of the two internal components that protect a CSP transformer is the ? . a.bi-metal link b.secondary breaker c.secondary current tap d.secondary fuse
B. Secondary breaker
An oil-filled transformer can withstand an overload of ? times the rated current for two seconds. a.4 b.10 c.22 d.25
D. 25
A follow-through current initiated by ? may overheat a transformer. a.a lightning arrester b.a Qualified Electrical Worker c.improper fusing d.lightning
D. Lightning
A ? fuse reduces nuisance fuse blowing from transient faults. a.K-link b.Kwik-link c.larger d.T-link
D. T-link
A surge arrestor is installed after the transformer primary terminal in order to stop overcurrent. Select one: True False
False
An isolation link of an underground transformer can be easily replaced in the field. Select one: True False
False
CSP transformers do not have an internal primary fuse and rely on a pole mounted open-link fuse for protection. Select one: True False
False
The KVA rating of a transformer decreases 3% for each degree below 30°C. Select one: True False
False
The neutral and ground connections are interconnected on a transformer and are therefore interchangeable. Select one: True False
False
The rating of a surge arrestor is specified at ? voltage as the circuit. a.a slightly higher b.a slightly lower c.the same level d.twice the
A. A slightly higher
A transformer can carry more current in January than in June. Select one: True False
True
Fuse size and speed are specified by the utility. Select one: True False
True
Heat and voltage surge are two reasons for insulation breakdown in a transformer. Select one: True False
True
A transformer fuse is coordinated so it will isolate a transformer before ? . a.downstream protection opens the primary circuit b.the customer's equipment is damaged c.the transformer's secondary opens d.upstream protection opens the primary circuit
d.upstream protection opens the primary circuit