AS114 - Lecture - Troubleshooting

Question 1

broken circuit / incomplete path for current flow means its a ____ _____

Answer 1

Open circuit

Question 2

Meter Indications on a Ohmmeter for an open circuit are:

Answer 2

Ohmmeter- RT will be infinite resistance

No needle movement on analog meter

OL on digital meter

location of open identified by showing infinite resistance across 2 point of circuit

all other resistance measurements will be normal

Question 3

Meter Indications on a Voltmeter for an open circuit are:

Answer 3

Voltmeter- ET will show normal system voltage

location of open identified by showing system (source) voltage across 2 points of circuit

there will be no other voltage drops in the circuit

Question 4

Meter Indications on a Ammeter for an open circuit are:

Answer 4

Ammeter- IT will be 0 amps (lower than normal in a parallel circuit)

Question 5

More resistance than there should be in the circuit is a fault known as

Answer 5

Added Resistance-

Question 6

Meter Indications on a Ohmmeter for added resistance read:

Answer 6

Ohmmeter- RT will be higher than normal

location of fault identified by showing higher resistance across 2 point of circuit (or resistance where there shouldn’t be any)

all other resistance measurements will be normal

Question 8

Meter Indications on a Voltmeter for added resistance read:

Answer 8

Voltmeter- ET will show normal system voltage

location of fault identified by showing higher than normal voltage drop across 2 points of circuit

all other voltage drops in the circuit will be lower than normal.

Question 9

Meter Indications on a Ammeter for added resistance read:

Answer 9

Ammeter- IT will be lower than normal

Question 10

When the current bypasses all or part of the load is know as

Answer 10

Short Circuit ( two types are Partial and Dead)

Question 11

When current is bypassing part of the electrical load

C/B or fuse may or may not pop
it is known as

Answer 11

Partial Short

Question 12

Meter Indications on a Ohmmeter for Partial Short Circuit read:

Answer 12

Ohmmeter- RT will be lower than normal

location of fault identified by showing no resistance (0 Ω) across 2 point of circuit

all other resistance measurements will be normal

Question 13

Meter Indications on a Voltmeter for Partial Short Circuit read:

Answer 13

Voltmeter- ET will show normal system voltage

location of fault identified by showing no voltage drop (0 v) across 2 points of circuit

all other voltage drops in the circuit will be higher than normal.

Question 14

Meter Indications on a Ammeter for Partial Short Circuit read:

Answer 14

Ammeter- IT will be higher than normal

Question 15

When the current is bypassing all of the electrical load

C/B or fuse will pop it is a:

Answer 15

Short Circuit

Question 16

Meter Indications on a Ohmmeter for Dead Short Circuit read:

Answer 16

Ohmmeter- RT will be 0 Ω

location of fault will be from the positive side of the battery/source across the load to ground.

Question 17

Meter Indications on a Voltmeter for Dead Short Circuit read:

Answer 17

Voltmeter- ET will show normal system voltage

location of fault cannot be identified with a voltmeter because power cannot be connected to the circuit (circuit breaker pops)

Question 18

Meter Indications on a Ammeter for Dead Short Circuit read:

Answer 18

Ammeter- IT will be higher than normal