Pins should be applied on what maximum centers?

• A. 18 inch centers
• B. 12 inch centers
• C. 6 inch centers
• D. 24 inch centers

Answer: (B)

Pins should be placed with a maximum center-to-center spacing of twelve inches. This spacing provides enough room for the pin insulators and their clamps to fit properly on the cross-arm while keeping the live parts separated to prevent arcing or interference between components. If pins are placed closer than twelve inches, the hardware can crowd together, complicating installation and reducing clearance, which raises the risk of contact or arcing under load and weather conditions. If the pins are spaced much wider, like eighteen or twenty-four inches, the arrangement can become unstable on the arm, worsen conductor geometry, and require different hardware or longer spans to maintain stability. Twelve inches strikes a practical balance, ensuring safe clearance, proper alignment, and stable mounting for typical distribution setups.