Master Electrician Practice Exam

In a hospital setting, what is the maximum rating for a branch circuit serving x-ray equipment using a hard service cord?

1. 20 amperes

2. 25 amperes

3. 30 amperes

4. 35 amperes

The correct answer is: 30 amperes

In a hospital setting, the appropriate maximum rating for a branch circuit serving x-ray equipment using a hard service cord is determined by the National Electrical Code (NEC) and the specific requirements for medical electrical equipment. For x-ray equipment, the NEC stipulates that the branch circuit must be capable of safely handling the load generated by the equipment while considering factors such as the continuous operation of the equipment and potential inrush currents. The maximum rating of 30 amperes is specified for circuits serving larger medical equipment due to its ability to manage the substantial power demands and to ensure safe operation without risk of overheating or tripping. This rating provides sufficient capacity for the typical current draw of x-ray machines while allowing for flexibility in equipment operation. Lower ratings would not suffice to handle the demands of x-ray equipment, which often operates at high currents, particularly during the start-up phase or under full load. On the other hand, higher ratings could potentially expose circuits to unsafe conditions, as they may not adequately protect against overloads specific to medical applications. Thus, 30 amperes is established as a standard to ensure safety, compliance, and effective operation of x-ray equipment in healthcare environments.