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# How much current is being used?

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Forumite
157 Posts
Forumite
I have a multimeter set on the 2m current range and I have a reading of 1.181 with a 2 showing at the decimal point when there is no load on the output.

This is from a voltage regulator for a lithium battery.

I want to know if I should put a switch in the circuit or is the reading minuscule?

What is the current being used?

## Replies

• Forumite
999 Posts
Forumite
What is the 2m current range - I assume 2 milliamps max deflection?

If so, you are pulling 1.181 milliamps

(Not sure what you mean about a 2 showing - unless that is the range indictor.)

Is it miniscule? It depends on the capacity of the battery. If it is a tiny watch battery then it's a lot. If it's an electric car battery it is miniscule
• edited 25 January at 1:04PM
Forumite
157 Posts
Forumite
edited 25 January at 1:04PM
Yes the 2 is the range indicator so 1.181 milliamps  seems about right.

The battery is a 18650 with a voltage regulator set at an output of 12 volts to power a waterpump for 3 seconds once or twice a day.

It is an automatic watering system.
• edited 24 January at 9:16PM
6.8K Posts
edited 24 January at 9:16PM
The 18650 battery is rated between 2600 and 3500mAh, so a draw of 1.2mA isn't going to flatten it too fast.
Edit: Some specs say 1200mAh, so see what your is rated at.

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• Forumite
999 Posts
Forumite
You can find out how long the battery will last (in hours) by dividing the capacity in mAh by 1.181