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variable load DC volt meter? Answered

I would like to build my own one of these with more settings and variable load and input voltages. Maybe someone has a more elegant solution?

Something that would fit in a small box or maybe even a something to put in between the DC source and my multimeter

Voltmeters



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lemonie

9 years ago

You want to read or control the power supply?

L

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NachoMahmalemonie

Reply 9 years ago

.  They are for reading battery voltage under load (in the neighborhood of 125-500mA, depending on battery, if I understood what I read).

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MentholNachoMahma

Reply 9 years ago

Absolutely right.

The variable load I was looking for is up to 1A(1000mA) but that would be correct.


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NachoMahmaMenthol

Reply 9 years ago

.  If I were going to build one, I'd use a meter, a rheostat that will handle about twice your expected power (see Ohm's Law), and a switch to swap the meter between volts and amps (see VOM schematics for wiring info). Adjust rheostat to get desired mA then switch to volts. It won't maintain constant current as the battery discharges, but it should be good enough for your purposes.

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Menthollemonie

Reply 9 years ago

I would want to read the powersupply under load.