UNI-T UT71C high battery current auto shutdown mode

[mij59]

Two weeks ago i  replaced the battery in my UT71C.
Yesterday i wanted use it and again the battery was flat.

I left the multimeter in the dc volt setting, and auto shutdown is on.
Turns out that the battery current in shutdown mode is about 1 mA !

Wondering if there is something wrong with the multimeter.
 

[Wytnucls]

I had a check on my 71B: After auto power off: 47uA
Depending on selection, normal current flow varies between 2.7mA and 8.2mA. It goes up to 20mA with full backlight on.

So, there is something wrong with your meter.

[mij59]

I had a check on my 71B: After auto power off: 47uA
Depending on selection, normal current flow varies between 2.7mA and 8.2mA. It goes up to 20mA with full backlight on.

So, there is something wrong with your meter.

Thank you, https://www.eevblog.com/forum/Smileys/default/icon_smile_thumbsup.gif

I also checked my Fluke 87V,  battery current is 50 uA in power down mode.

[mij59]

So, there is something wrong with your meter.

Seems like the uc is not in sleep mode.

[Wytnucls]

Try different timings for the APO setting if you haven't done that yet.

If you have the equipment, you can check that the 'sleep' bit goes high when the uC commands APO.
If the signal is correct and the meter enters APO, but the quiescent current is too high, the Cyrustek iC may be faulty.

If everything else if fine, live with the fault, otherwise Cyrustek could send you a new ES51966, if you ask nicely.

[mij59]

If you have the equipment, you can check that the 'sleep' bit goes high when the uC commands APO.

Checked, sleep bit is set just before the meter enters power down mode.

I will leave the meter as it is.

Thank for the support.

[Wytnucls]

Might be worth checking the 3.7mA on Vdc during normal operation. If it is reading more than that by a wide margin, there might be leakage somewhere else.

[mij59]

Might be worth checking the 3.7mA on Vdc during normal operation. If it is reading more than that by a wide margin, there might be leakage somewhere else.

Battery current varies a bit, average is about 4,5 mA, seems ok.