 |
Matronics Email Lists
Web Forum Interface to the Matronics Email Lists
|
| View previous topic :: View next topic |
| Author |
Message |
pwmac(at)sisna.com
Guest
|
 Posted: Tue Jan 25, 2011 8:16 am Post subject: VOMs again. . . |
 |
|
Sure Lots of message for good meters. And the HF $4 unit is great for
checking voltages and continuity.
What about a low cost meter that can be used for low resistance
measurements? No need to go down to less than ~2 ohms. But a 20k
lower scale dosen't do much for my needs and I have to drag out my
ancient VTVM to see the resistance. I sure would be nice to have a
handy VOM that gets some low R values.
Any suggestions?
Like to measure sensors on my truck that are supposed to be 3 ohm.
and the truck is 1000 miles from the VTVM because I only carry the
cheepy VOM and leave the VTVM home. - Sigh.
PaulW
| | - The Matronics AeroElectric-List Email Forum - | | | Use the List Feature Navigator to browse the many List utilities available such as the Email Subscriptions page, Archive Search & Download, 7-Day Browse, Chat, FAQ, Photoshare, and much more:
http://www.matronics.com/Navigator?AeroElectric-List |
|
|
|
| Back to top |
|
 |
mdnanwelch7(at)hotmail.co
Guest
|
| Posted: Tue Jan 25, 2011 9:01 am Post subject: VOMs again. . . |
|
|
>I sure would be nice to have a
| Quote: | handy VOM that gets some low R values.
Any suggestions?
PaulW
|
Paul,
When this subject came up a couple of months ago, I had recommended
the Etek digital VOM, model #10709, sold at Walmart. It has a good feel in
your hands, and several extra functions (built-in flashlight, temp probe, etc.)
that make it a GREAT model for the money.
I had one I used in doing the electrics for my house I was building. Someone
ruined it by spilling coffee in it. I did like it, so I made it a point of going
back to Walmart and getting another one!
For $21 you simply can't go wrong!
Mike Welch
[quote][b]
| | - The Matronics AeroElectric-List Email Forum - | | | Use the List Feature Navigator to browse the many List utilities available such as the Email Subscriptions page, Archive Search & Download, 7-Day Browse, Chat, FAQ, Photoshare, and much more:
http://www.matronics.com/Navigator?AeroElectric-List |
|
|
|
| Back to top |
|
|
handainc(at)madisoncounty
Guest
|
| Posted: Tue Jan 25, 2011 9:23 am Post subject: VOMs again. . . |
|
|
The WalMart stores in our area no longer sell that model - what they've got in stock is just junk. Since my wasn't working, I took it back to get it replaced, and they no longer stock it. I'm trying to find another one now since I've got all the leads and everything.
M. Haught
On 1/25/2011 10:57 AM, Mike Welch wrote: [quote] >I sure would be nice to have a
> handy VOM that gets some low R values.
> Any suggestions?
> PaulW
Paul,
When this subject came up a couple of months ago, I had recommended
the Etek digital VOM, model #10709, sold at Walmart. It has a good feel in
your hands, and several extra functions (built-in flashlight, temp probe, etc.)
that make it a GREAT model for the money.
I had one I used in doing the electrics for my house I was building. Someone
ruined it by spilling coffee in it. I did like it, so I made it a point of going
back to Walmart and getting another one!
For $21 you simply can't go wrong!
Mike Welch
[b]
| | - The Matronics AeroElectric-List Email Forum - | | | Use the List Feature Navigator to browse the many List utilities available such as the Email Subscriptions page, Archive Search & Download, 7-Day Browse, Chat, FAQ, Photoshare, and much more:
http://www.matronics.com/Navigator?AeroElectric-List |
|
|
|
| Back to top |
|
|
pwmac(at)sisna.com
Guest
|
| Posted: Tue Jan 25, 2011 11:14 am Post subject: VOMs again. . . |
|
|
Mike what was it R scale? Max value?
PW
========
At 08:57 AM 1/25/2011, Mike Welch wrote:
| Quote: | >I sure would be nice to have a
> handy VOM that gets some low R values.
> Any suggestions?
> PaulW
Paul,
When this subject came up a couple of months ago, I had recommended
the Etek digital VOM, model #10709, sold at Walmart. It has a good feel in
your hands, and several extra functions (built-in flashlight, temp
probe, etc.)
that make it a GREAT model for the money.
I had one I used in doing the electrics for my house I was
building. Someone
ruined it by spilling coffee in it. I did like it, so I made it a
point of going
back to Walmart and getting another one!
For $21 you simply can't go wrong!
Mike Welch
|
| | - The Matronics AeroElectric-List Email Forum - | | | Use the List Feature Navigator to browse the many List utilities available such as the Email Subscriptions page, Archive Search & Download, 7-Day Browse, Chat, FAQ, Photoshare, and much more:
http://www.matronics.com/Navigator?AeroElectric-List |
|
|
|
| Back to top |
|
|
nuckolls.bob(at)aeroelect
Guest
|
| Posted: Tue Jan 25, 2011 11:18 am Post subject: VOMs again. . . |
|
|
At 11:07 AM 1/25/2011, you wrote:
| Quote: | --> AeroElectric-List message posted by: paul wilson <pwmac(at)sisna.com>
Sure Lots of message for good meters. And the HF $4 unit is great for checking voltages and continuity.
What about a low cost meter that can be used for low resistance measurements? No need to go down to less than ~2 ohms. But a 20k lower scale dosen't do much for my needs and I have to drag out my ancient VTVM to see the resistance. I sure would be nice to have a handy VOM that gets some low R values.
Any suggestions? |
Only my brother-in-law would get such a deal as I
have for you. See:
http://tinyurl.com/4l3tuj6
A few years back we were wrestling with some switch
and relay issues on fielded airplanes that required
accurate measurements below 1 ohm. As you've noted,
most multimeters don't have the resolution to tell
you much about low resistances. Further, the resistance
of the test leads become a significant portion of
the total resistance being measured.
I crafted a series of devices cited in the article
above. This paper was published to the HBC field
service community.
Setting up the adapter to generate a 0.1 amp
constant current means that resistance across
the 4-wire test connections has a voltage drop of
of 100 mV/ohm. So a reading of 1 volt indicates
a resistance value of 10 ohms. LM317 needs to
have about 2 volts of head-room so the 3 cell
instrument should not be depended on for
measurements above 20 ohms. The 4-cell
instrument can go up to 35 ohms. Depending
on resolution of your VOM, you can accurately
resolve very small resistance values. For
example, the HF $4 VOM on the 200 mV scale
displays 199.9 millivolts. The instrument
display offers you 1 milliom resolution at
2.0 ohms full scale.
Many small, low cost VOMs don't have 3/4"
spaced banana jacks. You can buy banana
plugs that mount on screws with a spacing
of your choice
[img]cid:.0[/img]
http://tinyurl.com/4d465gx
Alternatively, you can build the larger
adapter that stands alone and connects
to your multimeter of choice with appropriate
wiring.
| Quote: | Like to measure sensors on my truck that are supposed to be 3 ohm. and the truck is 1000 miles from the VTVM because I only carry the cheepy VOM and leave the VTVM home. - Sigh.
PaulW |
Build one of these critters up. You'll
be glad you did. I made up several and
gave them to guys in the shops.
Bob . . .
| | - The Matronics AeroElectric-List Email Forum - | | | Use the List Feature Navigator to browse the many List utilities available such as the Email Subscriptions page, Archive Search & Download, 7-Day Browse, Chat, FAQ, Photoshare, and much more:
http://www.matronics.com/Navigator?AeroElectric-List |
|
| Description: |
|
| Filesize: |
22.67 KB |
| Viewed: |
3035 Time(s) |
|
|
|
| Back to top |
|
|
mdnanwelch7(at)hotmail.co
Guest
|
| Posted: Tue Jan 25, 2011 11:42 am Post subject: VOMs again. . . |
|
|
Hi Paul,
20M, 2M, 200K, 20K, 2K & 200. Marvin was right about them not being
at Walmart, it appears. I did a Walmart online search, and they didn't come up.
I checked on eBay. There are two different sellers. One guy wants $40 + sh.
The other guy wants $32 total. Walmart sold them at $20-$21, but they were
quite a deal at that, IMO. Here's the cheaper guy's auction;
http://cgi.ebay.com/ebaymotors/E-Tek-10709-Professional-Digital-Multimeter-_W0QQcmdZViewItemQQhashZitem41563d5b42QQitemZ280619735874QQptZMotorsQ5fCarQ5fTruckQ5fPartsQ5fAccessories
> Date: Tue, 25 Jan 2011 11:08:51 -0800
[quote] To: aeroelectric-list(at)matronics.com
From: pwmac(at)sisna.com
Subject: RE: AeroElectric-List: VOMs again. . .
--> AeroElectric-List message posted by: paul wilson <pwmac(at)sisna.com>
Mike what was it R scale? Max value?
PW
| | - The Matronics AeroElectric-List Email Forum - | | | Use the List Feature Navigator to browse the many List utilities available such as the Email Subscriptions page, Archive Search & Download, 7-Day Browse, Chat, FAQ, Photoshare, and much more:
http://www.matronics.com/Navigator?AeroElectric-List |
|
|
|
| Back to top |
|
|
nuckolls.bob(at)aeroelect
Guest
|
| Posted: Tue Jan 25, 2011 2:50 pm Post subject: VOMs again. . . |
|
|
At 11:07 AM 1/25/2011, you wrote:
| Quote: | --> AeroElectric-List message posted by: paul wilson <pwmac(at)sisna.com>
Sure Lots of message for good meters. And the HF $4 unit is great for checking voltages and continuity.
What about a low cost meter that can be used for low resistance measurements? No need to go down to less than ~2 ohms. But a 20k lower scale dosen't do much for my needs and I have to drag out my ancient VTVM to see the resistance. I sure would be nice to have a handy VOM that gets some low R values.
Any suggestions? |
Only my brother-in-law would get such a deal as I
have for you. See:
http://tinyurl.com/4l3tuj6
A few years back we were wrestling with some switch
and relay issues on fielded airplanes that required
accurate measurements below 1 ohm. As you've noted,
most multimeters don't have the resolution to tell
you much about low resistances. Further, the resistance
of the test leads become a significant portion of
the total resistance being measured.
I crafted a series of devices cited in the article
above. This paper was published to the HBC field
service community.
Setting up the adapter to generate a 0.1 amp
constant current means that resistance across
the 4-wire test connections has a voltage drop of
of 100 mV/ohm. So a reading of 1 volt indicates
a resistance value of 10 ohms. LM317 needs to
have about 2 volts of head-room so the 3 cell
instrument should not be depended on for
measurements above 20 ohms. The 4-cell
instrument can go up to 35 ohms. Depending
on resolution of your VOM, you can accurately
resolve very small resistance values. For
example, the HF $4 VOM on the 200 mV scale
displays 199.9 millivolts. The instrument
display offers you 1 milliom resolution at
2.0 ohms full scale.
Many small, low cost VOMs don't have 3/4"
spaced banana jacks. You can buy banana
plugs that mount on screws with a spacing
of your choice
[img]cid:7.1.0.9.0.20110125164501.01d8a3a0(at)aeroelectric.com.1[/img]
http://tinyurl.com/4d465gx
Alternatively, you can build the larger
adapter that stands alone and connects
to your multimeter of choice with appropriate
wiring.
| Quote: | Like to measure sensors on my truck that are supposed to be 3 ohm. and the truck is 1000 miles from the VTVM because I only carry the cheepy VOM and leave the VTVM home. - Sigh.
PaulW |
Build one of these critters up. You'll
be glad you did. I made up several and
gave them to guys in the shops.
Bob . . .
| | - The Matronics AeroElectric-List Email Forum - | | | Use the List Feature Navigator to browse the many List utilities available such as the Email Subscriptions page, Archive Search & Download, 7-Day Browse, Chat, FAQ, Photoshare, and much more:
http://www.matronics.com/Navigator?AeroElectric-List |
|
| Description: |
|
| Filesize: |
22.67 KB |
| Viewed: |
3030 Time(s) |
|
|
|
| Back to top |
|
|
pwmac(at)sisna.com
Guest
|
| Posted: Tue Jan 25, 2011 3:17 pm Post subject: VOMs again. . . |
|
|
Bob, I remember this article well, which is why I asked if something is out there to buy. I seriously doubt a succesful build of your device considering my abilities.
Maybe you would consider a new product to sell us or even a kit?
Thanks, PaulW
=========
At 10:14 AM 1/25/2011, you wrote:
[quote]At 11:07 AM 1/25/2011, you wrote:
| Quote: | --> AeroElectric-List message posted by: paul wilson <pwmac(at)sisna.com>
Sure Lots of message for good meters. And the HF $4 unit is great for checking voltages and continuity.
What about a low cost meter that can be used for low resistance measurements? No need to go down to less than ~2 ohms. But a 20k lower scale dosen't do much for my needs and I have to drag out my ancient VTVM to see the resistance. I sure would be nice to have a handy VOM that gets some low R values.
Any suggestions? |
Only my brother-in-law would get such a deal as I
have for you. See:
http://tinyurl.com/4l3tuj6
A few years back we were wrestling with some switch
and relay issues on fielded airplanes that required
accurate measurements below 1 ohm. As you've noted,
most multimeters don't have the resolution to tell
you much about low resistances. Further, the resistance
of the test leads become a significant portion of
the total resistance being measured.
I crafted a series of devices cited in the article
above. This paper was published to the HBC field
service community.
Setting up the adapter to generate a 0.1 amp
constant current means that resistance across
the 4-wire test connections has a voltage drop of
of 100 mV/ohm. So a reading of 1 volt indicates
a resistance value of 10 ohms. LM317 needs to
have about 2 volts of head-room so the 3 cell
instrument should not be depended on for
measurements above 20 ohms. The 4-cell
instrument can go up to 35 ohms. Depending
on resolution of your VOM, you can accurately
resolve very small resistance values. For
example, the HF $4 VOM on the 200 mV scale
displays 199.9 millivolts. The instrument
display offers you 1 milliom resolution at
2.0 ohms full scale.
Many small, low cost VOMs don't have 3/4"
spaced banana jacks. You can buy banana
plugs that mount on screws with a spacing
of your choice
[img]cid:7.1.0.9.0.20110125143417.01e81300(at)sisna.com.1[/img]
http://tinyurl.com/4d465gx
Alternatively, you can build the larger
adapter that stands alone and connects
to your multimeter of choice with appropriate
wiring.
| Quote: | Like to measure sensors on my truck that are supposed to be 3 ohm. and the truck is 1000 miles from the VTVM because I only carry the cheepy VOM and leave the VTVM home. - Sigh.
PaulW |
Build one of these critters up. You'll
be glad you did. I made up several and
gave them to guys in the shops.
Bob . . . [b]
| | - The Matronics AeroElectric-List Email Forum - | | | Use the List Feature Navigator to browse the many List utilities available such as the Email Subscriptions page, Archive Search & Download, 7-Day Browse, Chat, FAQ, Photoshare, and much more:
http://www.matronics.com/Navigator?AeroElectric-List |
|
|
|
| Back to top |
|
|
|
|
You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot vote in polls in this forum
You cannot attach files in this forum
You can download files in this forum
|
Powered by phpBB © 2001, 2005 phpBB Group
|
Get Email Distribution Too!
FAQ
Search
Memberlist
Usergroups
Register
Profile
Log in to check your private messages
Log in
