Vertical runs of metal wireways should be securely supported at intervals not exceeding ____ feet.

In electrical installation practices, the proper support of vertical runs of metal wireways is crucial for ensuring safety and compliance with electrical codes. Vertical wireways are typically required to be supported to prevent sagging, which can lead to mechanical stresses and potential damage to electrical conductors over time.

The support interval specified in the codes assists in maintaining the integrity of the wireway, protecting the wiring from physical damage, and ensuring that connections remain secure. Specifically, the standard support spacing for vertical runs of metal wireways is established to be no farther than 20 feet apart. This distance allows for adequate support while also providing flexibility during installation.

By adhering to this 20-foot support requirement, electricians help ensure that the wireways will function properly over their lifespan, facilitate easier access for future maintenance, and promote overall safety in electrical systems. It's essential to understand this requirement for both compliance with electrical codes and for maintaining good practices in the field.