need advice for multimeter with pc interface

This is the place for any magazine-related discussions that don't fit in any of the column discussion boards below.
Post Reply
skrallman
Posts: 26
Joined: Tue Jan 07, 2003 1:01 am
Location: Coeur d'Alene, ID
Contact:

need advice for multimeter with pc interface

Post by skrallman » Mon Apr 07, 2003 10:09 am

I'm want to buy a multimeter that I can interface with my pc, primarily for data logging.
Does anyone have and experience with these or any advice?<p>CSI345 $39.95 http://www.circuitspecialists.com/prod.itml/icOid/4003
or
Radio Shack #22-812 $49.99
Thanks
Scott

User avatar
MrAl
Posts: 3862
Joined: Fri Jan 11, 2002 1:01 am
Location: NewJersey
Contact:

Re: need advice for multimeter with pc interface

Post by MrAl » Tue Apr 08, 2003 1:18 am

Hello,<p>What is it you want to know about them?<p>I ended up creating my own software for the
interface not being satisfied at all with what
came with the meter.<p>Also, remember you have to have your computer
running all the while when you are logging data.
This may mean you want to have a dedicated comp
just for that. The good news is that the interface
is usually slow, much less then 28k bits per sec,
so you can use an old computer and still be able
to log data.<p>Good luck with your circuits,
Al
LEDs vs Bulbs, LEDs are winning.

skrallman
Posts: 26
Joined: Tue Jan 07, 2003 1:01 am
Location: Coeur d'Alene, ID
Contact:

Re: need advice for multimeter with pc interface

Post by skrallman » Tue Apr 08, 2003 12:01 pm

I guess I didn't really have any specific questions about the meters. Just wondering if there were any strong opinions about them.
For right now I just want to monitor battery charging and discharging. I've made a NIMH battery charger but I dont think its terminating at the correct time - I've been data logging with a pencil and a stop watch and its getting kind of old.
Scott

grant fair
Posts: 184
Joined: Sun Feb 23, 2003 1:01 am
Location: Toronto
Contact:

Re: need advice for multimeter with pc interface

Post by grant fair » Tue Apr 08, 2003 9:55 pm

I have an older RS# 22-168. The software is slow and simple, but for simple logging it is fine. I tried writing some QuickBasic code to read it, but did not succeed. If autoranging capacity is available and works while datalogging, that can be a distinct advantage. (Mine is not autoranging).<p>If it does not log and autorange at the same time, when the range of your input swings beyond the limits of one range you have no meaningful data, other than 'out of range'. You can manually change ranges but then you need to keep an eye on it.<p>Good luck.<p>Grant
Grant

User avatar
MrAl
Posts: 3862
Joined: Fri Jan 11, 2002 1:01 am
Location: NewJersey
Contact:

Re: need advice for multimeter with pc interface

Post by MrAl » Thu Apr 10, 2003 1:40 am

scottk:
That's why i got my meter too, to log batteries as they were charged and
discharged.
Since the meter i got only has one input, you can only monitor voltage
or current but not both at the same time. Two inputs would have
been much better. I ended up using a constant current load and monitored
the voltage.
I was also thinking of building a multiplexing
circuit to switch between current and voltage
measurement, every other second or so.<p>GrantFair:
Interesting, i think i used QBasic for my first computer interface, then
moved on to a language called "Euphoria" that is quite a step up from
QBasic and allows you to create windows and controls. All the program
did was to check the meter every 2 seconds or something and write the
result to a text file for later reviewing. The format the meters use
is fairly simple.<p>Good luck with your circuits,
Al
LEDs vs Bulbs, LEDs are winning.

myp71
Posts: 585
Joined: Wed Apr 23, 2003 1:01 am
Location: Colorado
Contact:

Re: need advice for multimeter with pc interface

Post by myp71 » Thu Apr 24, 2003 9:49 pm

I have a digital multimeter R.S cat. no 22-805 I think that it works great along with the meter for
a battery monitor to monitor solar battery charging.

skrallman
Posts: 26
Joined: Tue Jan 07, 2003 1:01 am
Location: Coeur d'Alene, ID
Contact:

Re: need advice for multimeter with pc interface

Post by skrallman » Fri Apr 25, 2003 7:49 am

Thanks everyone,
I ended up getting the RS meter.
MrAl: Good point about two inputs. I looked around, but the price seemed to go up dramatically.
Does anyone know why most of the meters log at only 1 sample/sec? If you were to write your own program could you increase the sample rate, or is the meter the limiting factor?<p>Thanks
Scott

Post Reply

Who is online

Users browsing this forum: No registered users and 51 guests