Reddit reviews SMAKN® Blue 0.28" Mini 2 Wire DC Voltmeter 2.50~30v Digital Display Voltmeter Gauge LED Voltage Detector
We found 3 Reddit comments about SMAKN® Blue 0.28" Mini 2 Wire DC Voltmeter 2.50~30v Digital Display Voltmeter Gauge LED Voltage Detector. Here are the top ones, ranked by their Reddit score.
Measuring range:DC 2.50~30V Two-wire accessMeasurement precision:0.01V(3-10V); 0.1V (10-30V)Display:Three 0.28 " LED digital tubeDisplay Color:bluePower supply same Source,self-Power
If you are in a hurry and want to spend a little more, Amazon. (Prime)
http://www.amazon.com/SMAKN-Voltmeter-3-0~30v-Digital-Detector/dp/B00M50SEYC/ref=sr_1_2?ie=UTF8&qid=undefined&sr=8-2&keywords=smakn+.28
If you're patient and frugal, Ebay. (Chinese shipping)
http://www.ebay.com/itm/301015797525?_trksid=p2059210.m2749.l2649&ssPageName=STRK%3AMEBIDX%3AIT
I ordered some off of ebay, but I got tired of waiting, so I got this guy from amazon
That switch would be connected in parallel to the voltage output or battery voltage and the voltmeter connected in series. The switch only needs to be rated for the current draw of your voltmeter.
http://www.amazon.com/Voltmeter-2-50~30v-Digital-Display-Detector/dp/B00M50SEYC/ref=pd_sim_hi_3?ie=UTF8&refRID=1DZFXRY28KSPPA0VVS0R
> "Current consumption: generally 5-15mA, less than 20mA"
So no, that switch doesn't need to be rated for the full current load of 20 amps.