Help regarding DC voltmeter.

Thread Starter


Joined Sep 21, 2008
Topic name: "DC voltmeter for 5V using PMMC movement. (Ifsd = 5μA , Rin = 250Ω)"

Points to be covered: 1) Introduction and review. 2) building blocks of the above. 3) Circuit/Block Diag. 4) Relevant literature 5) Applications and future scope.

I think I can manage with the intro and review part, no big deal there. What I am confused in, however, is regarding the buliding blocks.

Umm, if my basic knowledge serves me right, all we have in a basic Voltmeter using PMMC is the PMMC and series multiplier resistor.

What Block diagram could one possibly do in it? The internet does show many weird Blocks.

Please help me as soon as possible.

Yash Arya.


Joined Apr 20, 2004
You have the resistance of the d'Arsonval movement and the current for full scale deflection. All you have to do is figure the series resistance that allows 5 volts to cause the FS current to flow through the meter movement.

Your term -
series multiplier resistor
- is incorrect. You're not multiplying anything, just limiting current.