BATTERY PLACEMENT

by Edwin J. Somers, CAS

Batteries… those indispensable little items that we all depend on for remote operation or backup. How many times have you put a cell in backwards? Come on now, admit it! I'll bet every one of you has done it at least once. Remember that panic battery change in the middle of the night, in total darkness, when the director was screaming at you?

With equipment using two or four cells, the mistake is usually very evident because of improper or non-operation after the battery change. What about the Nagra or a field mixing panel that used a dozen D cells? If you accidentally put a cell in backwards, it will still work fine and is hard to detect. They do make batteries very distinctive in appearance to reduce the problem, but it still happens.

What is the effect of this mistake? A reversed cell will still conduct; however, the battery voltage will be several volts lower, and that is a very easy warning sign to miss. Now, for the bad news: That cell will discharge very quickly, rupture, and release very caustic liquid electrolyte. If the equipment is stored in a position where the electrolyte leaks onto circuit boards and chassis parts, they will be destroyed and will have to be replaced. It is almost impossible to stop this corrosion once it starts.

If you open a battery compartment and find leaking cells, and none of them are reversed, take a good photograph before removing the batteries. Battery manufacturers will not warranty equipment where a cell has been reversed.

My recommendation is to be extremely careful during a battery change, take it very seriously, and don't let anyone rush you.