Battery use

Discussion about the new DM41X calculator
EM41
Posts: 160
Joined: Mon Mar 30, 2020 12:10 am
Location: Overijssel Netherlands

Battery use

Post by EM41 »

The 41X battery indicator was at 50% when I received it and I managed to burn the rest of the capacity in 3 days.
Now I have to admit that I was more or less playing with the thing all day :D .
I put a new Duracell battery in and after 2 days battery is 80% V=2,7V and slowly going down.

I have the feeling that this is going too fast, what is a normal battery life in hours programming/playing in SLOW mode
Its on USB now most of time and I can see the processor speed nicely change in SLOW FAST and USB mode.
Auto switch off works fine also.

In diagnostics there are different power modes, my HW version = 2 but the manual does not give a default value for it.
Is there any effect on power drain.

Erik
HP41C (2x), HP41CV, HP41CX, DM41X β, DM41X, DM42, HP11C, HP48G, HP97
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Walter
Posts: 1715
Joined: Tue May 02, 2017 11:13 am
Location: Close to FRA, Germany

Re: Battery use

Post by Walter »

EM41 wrote:
Wed Apr 08, 2020 12:49 pm
Is there any effect on power drain.

Erik
Shall I confirm your statement or do you want to ask a question??
DM42 SN: 00041 β
WP 43S running on this device

HP-35, HP-45, ..., HP-35S, WP 34S, WP 31S, DM16L
EM41
Posts: 160
Joined: Mon Mar 30, 2020 12:10 am
Location: Overijssel Netherlands

Re: Battery use

Post by EM41 »

Walter wrote:
Wed Apr 08, 2020 1:07 pm
EM41 wrote:
Wed Apr 08, 2020 12:49 pm
Is there any effect on power drain.

Erik
Shall I confirm your statement or do you want to ask a question??
The statement was a question (? missing and without proper preamble)
What I like to know, is it useful to play with this setting to minimise battery use ?
Is there a preferred setting for HW V2 ?
HP41C (2x), HP41CV, HP41CX, DM41X β, DM41X, DM42, HP11C, HP48G, HP97
Olivier de Nantes
Posts: 83
Joined: Mon Mar 16, 2020 9:37 am
Location: France

Re: Battery use

Post by Olivier de Nantes »

Just a question.

You calculate the battery level by the number of bars in the battery indicator or is there a way (like for DM42) to know the voltage of the battery (and to display it, again like DM42) ?

Olivier
Olivier de Nantes (Bretagne)


HP41 (x3 : 2CV / 1CX), HP 42S, HP 48G+, HP 71B, HP 15C LE, HP 35S, HP PRIME

DM41L, DM 41X (Beta - SN: 00078), DM 42 (SN: 1028)
EM41
Posts: 160
Joined: Mon Mar 30, 2020 12:10 am
Location: Overijssel Netherlands

Re: Battery use

Post by EM41 »

Olivier de Nantes wrote:
Wed Apr 08, 2020 2:57 pm
Just a question.

You calculate the battery level by the number of bars in the battery indicator or is there a way (like for DM42) to know the voltage of the battery (and to display it, again like DM42) ?

Olivier
Yes it is under setup, 4 system, 2 system menu, 8 selftest, 5 diagnostics
You cannot exit diagnostics but it times out in a few minutes.
batt is 2,7V now
HP41C (2x), HP41CV, HP41CX, DM41X β, DM41X, DM42, HP11C, HP48G, HP97
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PierreMengisen
Posts: 127
Joined: Wed Nov 29, 2017 1:38 pm
Location: Neuchâtel CH

Re: Battery use

Post by PierreMengisen »

I am surprised to see that the voltage indicated is accurate to 1/1000 of a Volt. Is this real? :geek:
Pierre
[TI59 with PC100C; TI-84 Plus CE-T; HP41CV with HP IL loop & 2*82161A DCD & 82162 TP; HP15C; HP28S; DM41; DM41L; DM42; DM41X]
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Walter
Posts: 1715
Joined: Tue May 02, 2017 11:13 am
Location: Close to FRA, Germany

Re: Battery use

Post by Walter »

PierreMengisen wrote:
Wed Apr 08, 2020 5:18 pm
I am surprised to see that the voltage indicated is accurate to 1/1000 of a Volt. Is this real? :geek:
Believe it or not ;)
DM42 SN: 00041 β
WP 43S running on this device

HP-35, HP-45, ..., HP-35S, WP 34S, WP 31S, DM16L
EM41
Posts: 160
Joined: Mon Mar 30, 2020 12:10 am
Location: Overijssel Netherlands

Re: Battery use

Post by EM41 »

You can see the last two digits of the voltage change up and down when you press a key.
Its not too difficult to measure 0.001 V resolution with a simple Successive approximation AD converter, even the measurement uncertainty could be reasonable. There is of course the calibration so in absolute terms this 0.001V resolution has no meaning.
HP41C (2x), HP41CV, HP41CX, DM41X β, DM41X, DM42, HP11C, HP48G, HP97
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PierreMengisen
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Location: Neuchâtel CH

Re: Battery use

Post by PierreMengisen »

1 tenth +/- 5 hundredths is enough for me. What's important to me is to always have a spare battery ... and a USB connection. :lol:
Pierre
[TI59 with PC100C; TI-84 Plus CE-T; HP41CV with HP IL loop & 2*82161A DCD & 82162 TP; HP15C; HP28S; DM41; DM41L; DM42; DM41X]
EM41
Posts: 160
Joined: Mon Mar 30, 2020 12:10 am
Location: Overijssel Netherlands

Re: Battery use

Post by EM41 »

PierreMengisen wrote:
Wed Apr 08, 2020 6:48 pm
1 tenth +/- 5 hundredths is enough for me. What's important to me is to always have a spare battery ... and a USB connection. :lol:
But how long does one battery last in hours, it seems one or two weeks max if i calculate the speed the voltage goes down with one hour a day on battery.
If this is not normal I will hook up my multimeter and a powersupply tomorrow to see the current.
This thing gives me a true HP41 with cardreader feeling :D
HP41C (2x), HP41CV, HP41CX, DM41X β, DM41X, DM42, HP11C, HP48G, HP97
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