Properties of an AC circuit which opposes any change in current? (Alternating current)
Resistance, Inductive reactance and Capacitive reactance.
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Describe impedance in AC circuit.
The total opposition to the current flow in an AC circuit consisting of either resistance and reactance, or elements of both capacitive or inductive.
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What is common use of most multimeters?
Troubleshooting and measurements of voltage, resistance, current continuity, Capacitance and inductance.
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Define Short Circuit.
Low resistance path between two poles (a component and/or a conductor and ground).
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Using a multimeter, how would a technician read current?
Inserting the multimeter in series by opening or breaking the circuit. The positive side of the meter (RED) is connected towards the positive voltage source.
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Why would you not perform a specific gravity check of electrolyte NI-CAD battery?
The specific gravity does not change with the state of charge.
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How many cells make up a lead-acid battery rated at 24 volts?
12 cells.
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When reading specific gravity of a fully charged lead-acid battery, what indicates high state of charge?
Specific gravity reading between 1.275 and 1.300.
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What is considered to be the open-circuit voltage of a fully charged 12 cell lead-acid battery?
Approximately 26.4 volts. Or (12 x 2.2 volts) 28 volts are required for charging.
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What is the open-circuit cell voltage of a NI-CAD battery?
1.25 volts.
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What is a hazard when storing NI-CAD batteries and lead-acid batteries in the same area?
The fumes from one type can contaminate the electrolyte in the other type.
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Can NI-CAD batteries be interchangeable with lead-acid types?
yes
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How does a capacitor store electricity?
In the form of an electrostatic charge or field that exists between two conductors separated by an insulator.
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What should be done when interchanging a NI-CAD battery with a lead-battery?
Clean, dried & neutralized with Boric acid or ammonia, then completely air/oven dried.
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What is a probable cause when troubleshooting a NI-CAD battery for failing to deliver its rated capacity?