Don’t scrimp on your digital multimeter
All Digital Meters are not alike
I have three cheapo meters, and I can’t get a consensus amongst the three. It’s really trying to try to chase down problems when none of your meters agree!
You’ve read that for real troubleshooting, many factory ‘battery level’ indicators are all but useless, and you’ve probably also seen that the old-style analog meters with the swinging needle are equally so.
The voltage difference between a fully charged 12 volt battery bank, vs. depleted to the point of needing recharging, for example, is only .4 volts DC. You just can’t tell with an inaccurate meter.
For the best results, get a high-impedance digital multimeter which measures to an accuracy of at least two decimal places. Just because it’s a digital meter though, don’t assume that it’s a high-impedance meter. A high-impedance meter draws no power from the circuit being measured and doesn’t affect the measurement you’re trying to take.
Even better, a true RMS meter if you’re dealing with AC voltages of the non-pure sine wave kind, which are the kind most non-expensive inverters supply. RMS is a way to calculate the effective value of a varying or alternating voltage.
The true RMS value is helpful when you need to measure an AC voltage that is not a pure sine wave. Most meters are calibrated with pure sine waves and measure average AC voltage. In measuring a pure sine wave, you get an accurate reading. But if the sine wave is not pure (like most inverters supply) responding meters display an incorrect value, by as much as 11 percent.
I don’t have web store so I’m not tryin’ to sell ya anything, I’m just sayin’…
