A helper staged aluminum USE-2 for a rooftop DC run, copper-only lugs in a combiner, and no anti-oxidant or torque tools for a hot coastal site. Which judgment about conductor and termination compatibility should the lead enforce before landing wires?

The required judgment is to use lugs rated for aluminum, prepare the conductors and lugs as instructed, apply inhibitor when the lug instructions call for it, torque to the maker’s specification with suitable tools, and provide protection for coastal salt exposure. Copper-only lugs are not suitable for the staged aluminum USE-2. Using aluminum-rated lugs, cleaning and compounding the conductors, and applying the specified torque is not enough if added coastal sealing is omitted; the connection still needs protection appropriate to the site. Preparing and sealing aluminum-rated lugs for salt air also falls short if inhibitor is omitted despite the lug instructions, because cleaning does not replace a specified preparation step. Aluminum-rated lugs, proper preparation, and specified torque likewise do not meet the requirement if the connection is left exposed to coastal salt spray. The complete approach combines compatible lugs, required preparation, specified torque, and coastal protection. A sound general practice may still be wrong when it omits a step required by the terminal instructions or installation conditions. Exam caveat: do not assume every aluminum termination requires the same inhibitor or sealing product; follow the lug listing, maker’s instructions, and applicable code. Practical check: verify the conductor and lug markings, confirm the required preparation and torque, and make sure the appropriate tools and corrosion-protection materials are available before landing.