All metallic conductors must be tested with a meter to verify stray voltages between the conductors and ground that exceed how many volt(s) ac/dc?

All metallic conductors must be tested with a meter to verify stray voltages between the conductors and ground that exceed how many volt(s) ac/dc?

• A. 1 volt
• B. 0.5 volt
• C. 2 volts
• D. 5 volts

Answer: (A)

Stray voltage on metallic conductors is checked to make sure there isn’t a potential that could cause nuisance alarms or contact hazards. In fire alarm installations, any difference between a conductor and ground that is greater than one volt (whether measured as AC or DC) is considered unacceptable and needs investigation. The reason one volt is used is that it’s a small, detectable level: most normal leakage or coupling may show tiny readings, but anything over one volt can indicate a grounding problem, insulation leakage, or improper bonding that could affect performance or safety. Values like half a volt are generally tolerated, while voltages in the couple-volt or higher range are clearly outside acceptable limits and demand corrective action.

Stray voltage on metallic conductors is checked to make sure there isn’t a potential that could cause nuisance alarms or contact hazards. In fire alarm installations, any difference between a conductor and ground that is greater than one volt (whether measured as AC or DC) is considered unacceptable and needs investigation. The reason one volt is used is that it’s a small, detectable level: most normal leakage or coupling may show tiny readings, but anything over one volt can indicate a grounding problem, insulation leakage, or improper bonding that could affect performance or safety. Values like half a volt are generally tolerated, while voltages in the couple-volt or higher range are clearly outside acceptable limits and demand corrective action.