Oklahoma Electrical Practice Exam

For the supply of incandescent signs, what is the load calculated at the largest of how many amperes?

1. 10 amperes

2. 15 amperes

3. 20 amperes

4. 25 amperes

The correct answer is: 20 amperes

When calculating the load for incandescent signs, the National Electrical Code (NEC) requires that the load be determined based on specific criteria designed to ensure safety and efficiency. In this case, the correct answer indicates that the load for these signs should be calculated at 20 amperes. This figure is derived from the NEC standards that set guidelines for the electrical load on circuits. For signage, especially where incandescent lighting is involved, a higher amperage is justified due to the greater power consumption associated with incandescent technology compared to other lighting sources. Incandescent lights typically require more current to operate effectively, thus necessitating a load calculation that accommodates this demand to prevent overloading circuits. Choosing 20 amperes allows for sufficient capacity to handle the operational needs of the signs while also providing a margin of safety. This amperage level takes into account both the typical requirements for light operation and expected fluctuations in power draw, which is particularly important in commercial settings where the signs may be used frequently and for extended periods. In summary, the selection of 20 amperes is not only aligned with the code requirements but ensures that the electrical system will be robust enough to support the signage without risking circuit overload or safety issues.