Multimeter question

Hi,

   Thank you for your question regarding Multimeter,it was not straight forward answer, I need some help from our supplier and they have suggested bench multimeter as shown below.

Thank you,

This is an interesting question, but I have to admit I am not sure I fully understand what a 'diverse successive  pulse shaped DC current' is exactly. I am scared to even take a punt on this, in case I get made to look a fool, but in the interest of collaboration I'll take a stab.

I think (I am going to make a lot of assumptions here) that a 'diverse successive  pulse shaped DC current' could be interpreted to be some sort of PWM signal. The signal modulation is occurring in some kind of repetitive pattern at 2-5Hz. maybe for example this is a test for a PWM dimmer being swept from lowest to highest setting repetitively (or something like that, but I could be way off base here). If this is the case, I think I would probably abandoned all hope of using a DMM and go for a scope with current probe. A good DSO should be able to integrate the measured current between the cursors, or you could extract the data and do the analysis offline. Admittedly a scope is not as accurate as a DMM, but I don't know what kind of accuracy is required, but as it's repetitive, you should be able to get some back by averaging successive captures.

Interestingly I took a look at the  34401A34401A also it's my fall back DMM of choice and what I did wonder was if increasing the integration time on a DC current measurement to 100 power line cycles might work as a fudge to get a reasonably accurate measurement but really I have no idea what this signal really looks like May its it just a 2-5Hz square wave

Ok, that's my thinking at the moment, but I'll keep musing over it. Would be nice if there was some more info available on the signal of interest and accuracy requirements, what's being driven etc.

Hi,

    I received reply from Our supplier, please if you can supply following information, which will help us to suggest right instrument.

"

It does say DC Current in the original question, so assumed it is DC.

I'd be more interested to know exactly what diverse successive  pulse shaped DC current means (hopefully a sketch of what the signal looks like) if I was your supplier, and what measurment accuracy is required.

Dear All,

my 2 cents thoughts

We can breakdown into 3 simple parts

diverse => Different kinds, behavior

successive => repeatitive

pulse shaped DC current => As the name per says

Below is an example (correct me if I am wrong) . I guess customer might be using this kind of pulses for some form of electrotherapy experiment.

Hi Edmund,

You could be right.

I was thinking it might be more along the lines of the below. For example if you program a pattern in to a pulse pattern generator say 110011101001111010 and then have it repeat at 2 to 5 Hz, I would think this could be described as a diverse (it's changing), successive (on each pulse) and shaped DC current. However I think that your example and mine prove a point, who knows exactly what's going on here, it's open to interpretation, and until there is more detail, it's difficult to advise one way or the other, as there could potentially be high frequency components in the signal which certain measurement solutions would filter out and therefore not take account of in any subsequent measurement.

(note: the red lines just indicate the start and stop of repeating pattern).

Hopefully the original poster will reply with some more info, if not, I don't think there much else I can add, so I'll get back to my real work

Hello,

        Thank you all for your help,it is very challenging , very interesting situation, but Agilent is trying to help us with this inquiry and I can give you Agilent contact details, if you can contact Agilent direct, they are willing to help you.