Electronics and Electrical Safety Flashcards

What is the maximum allowable chassis leakage current for a patient-connected device in a general care area according to NFPA 99?

Answer: 100 µA

NFPA 99 limits chassis leakage current to 100 µA for patient-connected equipment in general care areas.

A Zener diode is primarily used in electronic circuits to:

Answer: Regulate voltage

Zener diodes operate in reverse breakdown to maintain a stable reference voltage, making them ideal for voltage regulation.

Which type of transformer configuration is used in medical-grade isolated power systems to prevent shock hazard?

Answer: Isolation transformer

Isolation transformers break the galvanic connection between utility power and the patient care area, preventing ground-fault shock.

In a series RLC circuit at resonance, the impedance is:

Answer: Minimum and purely resistive

At resonance, XL and XC cancel each other, leaving only resistance, so impedance is at its minimum and purely resistive.

What does the term 'macroshock' refer to in electrical safety?

Answer: Large current entering the body through the skin

Macroshock involves relatively large currents (milliamps) applied externally to the body, typically causing ventricular fibrillation at 100 mA.

A hospital-grade receptacle differs from a standard commercial receptacle primarily by:

Answer: Green dot marking and reinforced contacts

Hospital-grade receptacles are identified by a green dot and feature stronger contacts and construction to withstand repeated plug insertions.

Which logic gate outputs HIGH only when all inputs are HIGH?

Answer: AND gate

An AND gate produces a HIGH output only when every input is simultaneously HIGH.