Q: I am redoing my voltage distribution panel and can’t decide between a needle movement voltmeter or a digital illuminated voltmeter to monitor my house and starting battery voltages. Which way would be best? — J. Henshaw, Tampa FL
GORDON WEST REPLIES
I would say do both types of voltage monitors! Here’s why. The digital illuminated meter will show as little as 1/10th volt excursions when different switches are flipped on from the panel. This lets you spot subtle draws off your house batteries, even with some gear turned off at the unit’s face. An analog needle voltmeter, on the other hand, is better when monitoring engine or generator starting. A good starting battery may deflect down to 11 volts during cranking, but you know it may be time for a new starting battery if you see the needle deflect down to 10 or 9 volts during engine cranking. The digital voltmeter likely won’t show this dynamic dip during engine cranking, but with both types, you’ve got all your bases covered.
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