Which bonding method is allowed for PBB connections?

• A. Exothermic or 2 Hole Irreversible Compression Lug
• B. Soldered joints only
• C. Twist-on wire connectors
• D. Crimp-only lugs

Answer: (A)

For PBB connections, the goal is a permanent, low-resistance bond that remains reliable under vibration, moisture, and temperature changes. Exothermic welding achieves this by melting and fusing the conductors together into a single, continuous metal path, creating a metallurgical bond that resists corrosion and loosening. A two-hole irreversible compression lug provides a crimped connection that, once set with the proper tool, cannot be easily undone and also delivers a solid, low-resistance bond suitable for bonding paths.

Soldered joints aren’t ideal in these environments because they can become brittle with thermal cycling and vibration, and they’re more susceptible to degradation over time. Twist-on wire connectors aren’t rated for the high-current, high-stress bonding roles required by PBB connections and can loosen. Crimp-only lugs may not guarantee the irreversible, non-loosening connection necessary for a dependable PBB bond unless they’re designed and installed to the specified irreversible crimp standard.