A handy 3 to 30 Vol meter

[Bob WilsonParticipant @bobwilson59101]

This may be of interest to R/C fans:

A handy little 3 to 30 Volt DC tester The meter module was obtained from Ebay, China (Post free) for a mere £1.20. I bolted it to a piece of 4mm brown acrylic, and put two input terminals and leads below the meter. Its range is 3 Volts to 30 Volts. After bolting it to the acrylic, it was still a bit too light, so I glued a piece of 0.35 inch-thick steel to the back (insulated from the terminals), to give it some weight. I will be using it to check my rechargeable 6V and 12V sealed lead acids. Its lowest reliable reading is 3 Volts! Very handy when I don't always want to dig my normal test meter out just to check the lead acids!

Bob

Edited By Bob Wilson on 19/12/2016 09:43:07

[Bob WilsonParticipant @bobwilson59101]

[ashley needhamParticipant @ashleyneedham69188]

Bob. That is a handy little meter to be sure.

Given your background I can understand your enthusiasm for little gizmos like this. I bet you would have loved to have this 40 years ago (or whenever) !!

​Unfortunately I have a cheap wattmeter gadget which I use to check current consumption and so on, and only have to plug this on to a battery to see what's watt. However for a bit of fault finding, a gizmo like this in the tool box could be a winner. It would be a bit fiddly but I suppose a Lipo on-board buzzer could be used for the same thing, with a bit of thin wire.

Ashley

[Bob WilsonParticipant @bobwilson59101]

Ashley,

Well, it only measures 3 to 30 Volts, but is quite convenient for checking my two lead acids, 6V and 12V. For anything more complicated, I use my multimeter. But this little device can be left next to the battery charger.

Can't really understand what you mean about the wattmeter. Just connecting to the battery could only show the voltage at best. To measure current, the meter has to be inserted in one of the leads!

Bob

[Dave MilbournParticipant @davemilbourn48782]

Bob

The type of 'wattmeters' which Ashley and I use are connected between the ESC and the battery pack. If you use the small tactile button on them you can cycle through voltage and current readings for their present values and also the maximum values achieved during a run. Mine also can act as a low-battery alarm **LINK**

For Kevin's continued education – as has been said often in this forum and elsewhere – you can't reliably tell how much capacity is left in any battery unless you actually run it flat while monitoring the current and time – which rather defeats the original objective!

Dave M

[Bob WilsonParticipant @bobwilson59101]

So part of it is in series, and the other part is across the voltage, so it can work out the wattage W = E x I. I can understand it now! Thanks.

Bob

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