220 Answers to Chapter Exercises
d. Leaking collector bars—can occur due to overheating and
leakage of bath at start-up or through later perimeter joint or
cathode slot failure. Such leakages can be sealed up and oper-
ated with successfully for years afterward as long as the original
leakage is documented and monitored regularly (collector bar
current distribution) from then onward.
e. High cathode voltage drop or large upward cathode heave—
probably indicative of cathode block failure that has resealed
itself with frozen bath. Needs to be removed from circuit within
a short period (2–3 months) and monitored intensively (iron,
cathode current distribution, noise, overheating) until this time.
f. Pots that are prone to high noise, d