What I must buy in order to measure mAh please

[DenisJ]

Thanks a lot... maybe I'll make one of this,
but now I need to buy one as soon is possible :-)

Denis

[skywatch]

@DenisJ in typical sleep mode it could take 6 or 7 days to register 1mAh. Maybe why you always see '0' in that range? What is the longest time period you left it to measure for?

[DenisJ]

Usually I let it now 30 seconds in order to see the value in sleep mode.
Today I just buy this one... I'll try it tomorrow.

Thanks a lot
Denis

[DenisJ]

I just retry with the newone and it give me about 9,1 uAmp :-)

Thanks all

[Nca78]

Having a common plug for mA and µA range as the one you bought is the minimum, else you have to unplug/re-plug before the nodes gets out of sleep and obviously this will make measurement impossible. Unfortunately a lot of cheap multimeters have a separate plug and are useless in this scenario.

Best is to find a multimeter with more digits and that can use them all in the µA range. With 20 000 count you can go up to 20mA which is usually enough to measure power consumption for both sleeping and running node.

[DenisJ]

@Nca78 said in What I must buy in order to misure mAh please:

you have to unplug/re-plug before the nodes gets out of sleep and obviously this will make measurement impossible.

I use the multimeters in this mode:
-first I musure the work mA in the work session, with the switch on mA... this give me about 19 mA
-then I put the switch on uA but I also put a direct wire that is in paralel to the multimeters in order to have suficient current
...when the Arduino go in sleep mode, I take out the direct wire and the remained wire of multimeter will misure the uA :-)

Thanks a lot for the answer.
Denis

[Nca78]

@DenisJ you can just wait for the arduino to be in sleep mode to switch from mA to uA.

[DenisJ]

Yes now I know :-)
But the tester that I had before this one,
when it was switching from mA to uA, it was reseting the board.

Now all is greate :-)
Thanks a lot

[OldSurferDude]

@DenisJ Are you measuring a USB device? Look at something like this https://www.aliexpress.com/item/33019457512.html?gps-id=pcDetail404&scm=1007.16891.96945.0&scm_id=1007.16891.96945.0&scm-url=1007.16891.96945.0&pvid=824c24fa-034b-4801-b51d-50b2ad877945&_t=gps-id:pcDetail404,scm-url:1007.16891.96945.0,pvid:824c24fa-034b-4801-b51d-50b2ad877945,tpp_buckets:668%230%23131923%2330_668%230%23131923%2330_668%23888%233325%239_668%23888%233325%239_668%232846%238110%231995_668%232717%237561%23332__668%233374%2315176%2335_668%232846%238110%231995_668%232717%237561%23332_668%233164%239976%23761_668%233374%2315176%2335

(AliExpress: Cheap prices and one could question the quality, but for the most part they work. Shipping takes about a month. rarely faster)

[DenisJ]

I already have something like this, but this one have no misurement in uAh
Thanks a lot
Denis