Author Topic: Hantek 1008 as super cheap 8 channel voltage logger?  (Read 3742 times)

0 Members and 1 Guest are viewing this topic.

Offline newmaster

  • Contributor
  • Posts: 11
  • Country: ee
Hantek 1008 as super cheap 8 channel voltage logger?
« on: December 29, 2015, 09:49:17 pm »
Hey

I´m not too familiar with Digital or PC oscilloscopes, so maybe someone can answer some questions about this unit.

my idea is to  make a device with integrated Lithium battery, and built in charger.  to test efficiency, I would like to record the charging and discharging from many test points at once.
I tried to find voltage/ current logger that could do that, but the prices are not worth it atm.

second idea was to build the logger myself.  based on Arduino for example, but there are some difficulties with that also.

then I saw this 8 channel PC "oscilloscope" and maybe I can use it?
could´nt find information I needed online, so maybe somebody who owns it, can answer?
(please excuse me if I dont know some of the technical words)

first and most important:  how many data points I can record, or is it only limited by my PC?  also, can I adjust the measuring resolution?  ( no need to take hundreds of samples per second if I´want to record battery discharging on the course of hours or even days.  a few samples per minute is more than enough)

are the input grounds isolated from each other?  (my system is mostly common ground, but battery ground to the charger is separate. hope that it makes sense)



things I want to log:
*5v charging input voltage and current
*battery voltage
*BMS output voltage and current
*boost converter output voltage and current

things I want to see or calculate from the results:
*battery charging and discharging time
*BMS overcharge cut-off voltage
*BMS over discharge cut-off voltage
*boost converter efficiency (at every given battery voltage and average value)

main reason to do all that is to test different charging and boosting modules.
could do it manually  :-DMM but I rather let the electrons do all the work.
 

Offline mtdoc

  • Super Contributor
  • ***
  • Posts: 3581
  • Country: us
Re: Hantek 1008 as super cheap 8 channel voltage logger?
« Reply #1 on: December 29, 2015, 10:05:33 pm »
I would think it is possible - though I doubt the included software supports extended data logging. It only has a memory depth of 4K (single channel) but as a PC oscilloscope you should be able to stream data to a disk at the slow speeds this scope allows. Likely to require custom software.

User manual is here
 

Offline artag

  • Frequent Contributor
  • **
  • Posts: 527
  • Country: gb
Re: Hantek 1008 as super cheap 8 channel voltage logger?
« Reply #2 on: December 30, 2015, 12:29:59 am »
I have one, but I haven't spent much time using it so answers are a bit vague.

There seems to be no indication that there is any ground isolation. However, I'm surprised to find that inputs 1-7 have a common ground but 8 is not connected. I can't see it being isolated on a cheap unit like this - it's probably just broken.

The PC software allows a timebase as long as 20000 secs per division, and a 16M acquisition file. Not sure what that works out to in samples (there's several samples per division , and 8 channels at 12 bits per channel) but it's probably quite a long time.

There doesn't seem to be any continuous logging facility - you just have to capture that 16M file and then save it.
 

Offline newmaster

  • Contributor
  • Posts: 11
  • Country: ee
Re: Hantek 1008 as super cheap 8 channel voltage logger?
« Reply #3 on: December 30, 2015, 04:38:16 pm »
it says in tha manual:  Horizontal:
scanning speed range (Sec/Div) : 1ns/div ~20000s/div (1-2-5 sequences)

i´m wondering what that last part means? 

but logically, when I could set the time base to 20000s/div, then it´s over 5,5 hours per division, and I hope it can record at least one screen, that is 10 divisions ( by the picture in the manual)  so I should have more than 2 days logging capability. then by single channel, it should be 1 sample every 50 seconds, or 7 channels sample every 350 seconds.

that is of course only if 2 things are true:  my logic has to be correct and this product has to be logically made  (in both cases I have some doubt )
 

Online Fungus

  • Super Contributor
  • ***
  • Posts: 11262
  • Country: 00
Re: Hantek 1008 as super cheap 8 channel voltage logger?
« Reply #4 on: December 30, 2015, 06:24:48 pm »
I'd use small Arduinos to build a system.

Pro Minis are a couple of $ each. Each has 8 analog inputs. I'd daisy-chain them all to an Arduino which communicate results to the PC via bluetooth. It could also have an SD card module in case you don't want to leave the PC switched on.

PS: I don't know if the Hantek 1008 will do what you want, it's all down to the software. Check very carefully before buying.
« Last Edit: December 30, 2015, 06:29:14 pm by Fungus »
 

Offline G7HUP

  • Newbie
  • Posts: 1
  • Country: gb
Hantek 1008 as 8 channel voltage logger- V drift is quite significant
« Reply #5 on: April 04, 2017, 09:30:58 am »
Hi,
Using the Hantek 1008C as a voltage logger for a the mentioned to record multiple channels over more than a minute is a nightmare due to the poor reference stability.

The only work around to log charge or discharge curves over minutes or an hour or two is to have a spare channel and short out the input to provide a reference as to the voltage drift, then load all the data into a spreadsheet and use it to massage the recorded against the reference.

The drift can be as much as a volt in one hour from initial 5 min wake up in hope of it settling..  Unfortunately not So.

Hantek support haven't come back to me with a fix as of yet to improve stability and I cant find a schematic anywhere to dabble to provide a mod to correct the issue, of which if I do find or come up with I'll share.

Good cheap item for simple fault finding on your Cars or for hobby and good value for what it is, but currently is a serious issue for logging such as charging or discharging voltage and current, or changes on channels for longer than a minute or longer

Mark T
 


Share me

Digg  Facebook  SlashDot  Delicious  Technorati  Twitter  Google  Yahoo
Smf