You can use an infrared pyrometer to analyze the temperature and cooling water flow to a stuffing box and make adjustments. Typically, stuffing-box temperatures should be no greater than 30 F above the ambient water temperature; if it’s warmer, the box is either overtightened or lacks sufficient water flow. Using the pyrometer to scan such energized DC circuits as batteries, battery connections, cables, switches, circuit breakers, and fuses can quickly identify areas of high resistance or impending faults. Batteries within the same bank should, while being charged, operate at roughly the same temperature. If one or more are significantly higher, it could mean that they’re either packed together too tightly—there should be at minimum a .25-inch gap separating batteries—or an internal short has developed.