Measure triangle wave with DC ammeter

Status
Not open for further replies.
K

kenw232

Newbie level 3
Joined
Jan 13, 2014
Messages
4
Helped
0
Reputation
0
Reaction score
0
Trophy points
1
Activity points
29
If I measure a positive only triangle/sawtooth wave with an analog DC ammeter will it give me a relatively accurate current measurement?
 

An everyday analog (D'Arsonval) movement automatically averages a waveform.

Suppose the triangle peaks are 1 A, troughs at zero. The average is 1/2 A. This is what your meter will read. (It can be derived geometrically based on the formula for the area of a triangle.)

When measuring current, the meter inserts a certain amount of resistance. A different resistor for each range. The highest ranges insert lesser ohms.

You must select the highest ampere range which gives a usable reading
 

Thanks for your response. This applies to extreme waveforms too then correct? Such as a 1200V sawtooth like the one measured here on my scope? This is being discharged from a .33uF capacitor, I'm trying to get a general measurement of the current.



I don't seem to have a way to adjust anything on my cheap DC analog ammeter.
 

Yes, it should give you a general measurement.

Here is a simulation, comparing the sawtooth waveform with unchanging DC.

The first circuit has an averaging circuit which resembles a meter movement.

By stopping the scope trace at the halfway point on the sawtooth, it confirms that current is the same as through the DC circuit.

 
Status
Not open for further replies.

Similar threads

Menu
Log in
Register
Cookies are required to use this site. You must accept them to continue using the site. Learn more…