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Products => Test Equipment => Topic started by: TomerP on August 19, 2017, 04:33:03 pm

Title: A DMM upto 20$ with PC connection for logging?
Post by: TomerP on August 19, 2017, 04:33:03 pm
Hi, is there a DMM with a PC connection for logging (either USB/COM) that also costs less than 20$?
Title: Re: A DMM upto 20$ with PC connection for logging?
Post by: jpb on August 19, 2017, 05:06:01 pm
It would probably need to be second hand if there was one.

If accuracy is not that important then alternatives such as the analogue inputs on a rasberry pi might be an option.
Title: Re: A DMM upto 20$ with PC connection for logging?
Post by: Lightages on August 19, 2017, 06:35:51 pm
The least expensive data logging meter that I know of is the Digitek DT-4000ZC, also known as TekPower TP4000ZC. They sell for around $40.
Title: Re: A DMM upto 20$ with PC connection for logging?
Post by: retiredcaps on August 19, 2017, 11:16:39 pm
Quote from: Lightages on August 19, 2017, 06:35:51 pm
The least expensive data logging meter that I know of is the Digitek DT-4000ZC, also known as TekPower TP4000ZC. They sell for around $40.
It first sold for around $29 USD when I brought it to Martin's attention 5+ years ago.  Then it got popular and sellers raised prices.

http://www.mjlorton.com/forum/index.php?topic=81.0 (http://www.mjlorton.com/forum/index.php?topic=81.0)

https://www.youtube.com/watch?v=kXzAD74C5As (https://www.youtube.com/watch?v=kXzAD74C5As)

https://www.youtube.com/watch?v=7pbRLom7bNc (https://www.youtube.com/watch?v=7pbRLom7bNc)
Title: Re: A DMM upto 20$ with PC connection for logging?
Post by: Fungus on August 21, 2017, 12:22:56 am
Quote from: TomerP on August 19, 2017, 04:33:03 pm
Hi, is there a DMM with a PC connection for logging (either USB/COM) that also costs less than 20$?

What do you need to measure? How accurate?
Title: Re: A DMM upto 20$ with PC connection for logging?
Post by: TomerP on August 28, 2017, 06:36:54 pm
Vdc and Current, as accurate as 1% I guess.
Title: Re: A DMM upto 20$ with PC connection for logging?
Post by: Fungus on August 28, 2017, 06:49:34 pm
Quote from: TomerP on August 28, 2017, 06:36:54 pm
Vdc and Current, as accurate as 1% I guess.

How many volts? How many amps? Will you need to switch voltage ranges or is it fixed?

Title: Re: A DMM upto 20$ with PC connection for logging?
Post by: TomerP on August 28, 2017, 07:00:16 pm
220v ac, much less dc, up to 30 amper (I don't know if its a reasonable requirement for that price range)
Title: Re: A DMM upto 20$ with PC connection for logging?
Post by: Fungus on August 28, 2017, 07:45:46 pm
Quote from: TomerP on August 28, 2017, 07:00:16 pm
220v ac, much less dc, up to 30 amper (I don't know if its a reasonable requirement for that price range)

a) You don't really need to measure 220V AC, it hardly ever gives a wrong value (not unless you're using a generator or something).
b) Look into current clamps for Arduino.

https://encrypted.google.com/search?q=arduino+current+clamp



Title: Re: A DMM upto 20$ with PC connection for logging?
Post by: TomerP on August 28, 2017, 08:45:15 pm
true, but measuring dc voltage of up to lets say 50v is something I'd like to be able to do with it
Title: Re: A DMM upto 20$ with PC connection for logging?
Post by: Fungus on August 28, 2017, 08:53:19 pm
Quote from: TomerP on August 28, 2017, 08:45:15 pm
true, but measuring dc voltage of up to lets say 50v is something I'd like to be able to do with it

Make a 10:1 resistor divider, connect it to the Arduino.