Oxidized Terminal Blocks - Continuous 300 C Temp
NORMALLY in a hostile environment, we would have recommended treating the surface DeoxIT ® contact cleaner first. If the area was seriously oxidized, we would have suggested either allowing the contacts/connectors to sit over night in a DeoxIT ® contact cleaner solution or simply applying the DeoxIT ® the night before, and wiping the oxidation off in the morning.
Once all the oxidation/contaminants were removed, we would have recommended treating the contact surface with DeoxIT ® SHIELD (formerly PreservIT) as a final step, making the surface impenetrable for quite a while.
IN YOUR CASE, due to the continuous temperature of 300c, it would probably be best to clean the area with the DeoxIT ®, as instructed above, and following with DeoxIT ® GOLD GxL (formerly ProGold GxL), which is specifically formulated to withstand temperatures up to 400c.
Your maintenance, under these adverse conditions, will be more often than someone whose application does not have a criteria as hostile as yours.