CBET Electronics and Electrical Safety 2

Question 1

What is the maximum allowable leakage current for a Type CF (cardiac floating) applied part according to IEC 60601-1?

Accepted Answer

10 microamps

Answer

Type CF applied parts must have a maximum patient leakage current of 10 microamps under normal conditions to prevent microshock.

Question 2

In a hospital electrical system, what is the purpose of an isolation transformer in an isolated power system?

Accepted Answer

To prevent ground-fault current from flowing through patients

Answer

An isolation transformer prevents ground-fault current from flowing through patients by electrically isolating the secondary circuit from ground.

Question 3

What component in an electrical circuit allows current to flow in only one direction?

Accepted Answer

Diode

Answer

A diode is a semiconductor device that allows current to flow in one direction (forward bias) while blocking current in the reverse direction.

Question 4

When measuring the resistance of a component with a multimeter, why must the circuit power be turned off first?

Accepted Answer

Because the multimeter supplies its own test current and external voltage will cause inaccurate readings

Answer

A multimeter in resistance mode supplies a small known current and measures the resulting voltage to calculate resistance. External circuit voltage would produce incorrect readings and could damage the meter.

Question 5

What is the purpose of a ground wire (green or green/yellow) in a medical device power cord?

Accepted Answer

To provide a low-impedance fault current path to trip the circuit breaker

Answer

The ground wire provides a low-impedance path for fault current to flow back to the source, tripping the circuit breaker quickly and protecting patients and staff.

CBET - Certified Biomedical Equipment Technician Practice Test

CBET - Certified Biomedical Equipment Technician Practice Test

CBET Electronics and Electrical Safety 2