Digital clamp on ammeter video - PeachParts Mercedes-Benz Forum

funola · #1 12-04-2011, 11:27 AM

I just bought one and used it to check my starter cranking current. Works great! I jumped the terminal block on the fender so the engine was not getting fuel or glow on the plugs. As can be seen, it averages around 300 amps. It'll come in handy for checking glow plugs with ease.

ps meter available at Radio Shack for $60. Got mine on Ebay for $24

CLICK TO PLAY!

Biodiesel300TD · #2 12-04-2011, 11:51 AM

Those work well for checking glow plugs as well. You can put it around the bundle of GP wires and see if it's pulling the right number of amps. I think each GP pulls about 20amps.

kerry · #3 12-04-2011, 11:55 AM

That's a great tool.

kerry · #4 12-04-2011, 12:42 PM

One question: Will the clamp fit around each of the glow plug wires? Aren't some of the wires in difficult enough locations to reach that the clamp won't fit?

funola · #5 12-04-2011, 12:57 PM

Quote:

Originally Posted by Biodiesel300TD

Those work well for checking glow plugs as well. You can put it around the bundle of GP wires and see if it's pulling the right number of amps. I think each GP pulls about 20amps.

Yep. Before I bought this digital clamp ammeter, I was using an inductive ammeter for 15 years. The digital one is much easier to use and more accurate.

Here's another video of the glow plugs. I turned them on before shooting the video so did not capture the initial turn on current. You can see the current dropping as they heat up. This one should be better quality since I selected higher quality pics on my new Android phone.

CLICK TO PLAY!

funola · #6 12-04-2011, 01:00 PM

Quote:

Originally Posted by kerry

One question: Will the clamp fit around each of the glow plug wires? Aren't some of the wires in difficult enough locations to reach that the clamp won't fit?

If you cut back the outer jacket on the bundle to the glow plug relay, you should be able to get the clamp around individual glow plug wires.

Stretch · #7 12-05-2011, 03:31 AM

Nice one funola - something else added to my long long Christmas wish list.

funola · #8 12-05-2011, 01:52 PM

Quote:

Originally Posted by Army

Nice one funola - something else added to my long long Christmas wish list.

Anyone who works on a car's electrical system should have one of these.

Here's a video on one glow plug. Note that it starts at 20 amps and drops to around 10 amps as it heats up. The chime in the backgound is an alert to let me know the glow plugs are on so I do not run down the battery if I forget to turn off the manual glow plugs.

By measuring a new glow plug's current and monitoring it as the glow plug age could tell you if the plug is wearing out (getting less hot) or not.

CLICK TO PLAY!

vstech · #9 12-06-2011, 06:24 AM

the tool is handy, and it's great that there is FINALLY a clamp on meter for DC, but the meter is NOT high quality. most of the readings are unreliable. temp, ac/voltage, heck, the dc amps is flaky it's a good thing they included the zero button...

DIESELVOLVO · #10 12-06-2011, 08:26 PM

I have had my "amp clamp" for about eight years now. I use it all the time and feel it is accurate enough for my needs. The only complaint I have is that is is sensitive to EF and can get a little wacky if you get it too close to the alt. or gen. when trying to get certain readings.

The glowplug test is one of my favorite uses for it. Multiply the amp draw per plug by the number of plugs and it is easy to tell if you have a plug out or not. You can also see if the amp draw decreases like it should over the duration of the glow cycle. Good video by the way. I always appreciate the folks who take the time to post stuff like that.

funola · #11 12-07-2011, 12:28 AM

Quote:

Originally Posted by vstech

the tool is handy, and it's great that there is FINALLY a clamp on meter for DC, but the meter is NOT high quality. most of the readings are unreliable. temp, ac/voltage, heck, the dc amps is flaky it's a good thing they included the zero button...

Digital DC clamp meters has been avaialable for a long time. They're nothing new. They were just very expensive but that has changed. You found a very affordable one. For the price I paid, I am happy with the accuracy, which is not bad. I'll do more testing with mine. I don't mind the zero button, I think it is necessary only on the amps function. I believe these meters use a hall effect sensor at the clamp gap and the zero button is necessary to cancel out stray currents in the vicinity before you take a measurement.

funola · #12 12-07-2011, 12:31 AM

Quote:

Originally Posted by DIESELVOLVO

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The glowplug test is one of my favorite uses for it. Multiply the amp draw per plug by the number of plugs and it is easy to tell if you have a plug out or not. You can also see if the amp draw decreases like it should over the duration of the glow cycle. Good video by the way. I always appreciate the folks who take the time to post stuff like that.

Yep, sure beats taking all the plugs out and powering them up one at a time and then putting them back in.

WINGAS · #13 12-07-2011, 05:08 AM

Man-o-man funola; I;m in "messin' with GPs" mode now and this would be a dream for diagnostics. Esp for $25 piasters! Thnx for sharing.

vstech · #14 12-07-2011, 08:14 AM

Quote:

Originally Posted by funola

Digital DC clamp meters has been avaialable for a long time. They're nothing new. They were just very expensive but that has changed. You found a very affordable one. For the price I paid, I am happy with the accuracy, which is not bad. I'll do more testing with mine. I don't mind the zero button, I think it is necessary only on the amps function. I believe these meters use a hall effect sensor at the clamp gap and the zero button is necessary to cancel out stray currents in the vicinity before you take a measurement.

heh, yeah... I should have said FINALLY an AFFORDABLE one is available... Fluke and other high end meters have had the feature for years, but ... well in excess of 150.00 no thank you.