DEE 2313: Instrumentation and Managements
Tutorial: Chapter2 (Part 1)
1. A 1mA meter movement with an internal resistance of 100Ω is to be converted into a 0 –
100mA. Calculate the value of shunt resistance required.
2. Design an Aryton shunt to provide an ammeter with current ranges 0 – 10mA, 100mA
and 500mA using a D’Arsonval movement having an internal resistance of 50Ω and full
scale deflections of 1mA.
3. An ammeter that has an internal resistance of 78Ω is used to measure the current
through resistor Rc. Determine the percentage of error of the reading due to ammeter
insertion.
Ra = 1 kO
E= 3V
Rb = 1 kO
Rc = 1 kO
4. A basic D’Arsonval movement with a full scale deflection of 50µA and internal resistance
of 500Ω is used as a voltmeter. Determine the value of the multiplier resistan ce needed
to measure a voltage range 0-10V.
5. Calculate the value of multiplier resistance for the multiple range DC voltmeter circuit as
shown in figure below. Given Rm=1kΩ and I fs = 50µA
5V
10V
50V
6. In the circuit below, two voltmeters are be used to measure the voltage across resistor
RB.
25kΩ
30V
5kΩ
Meter A: S=1kΩ/V, range=10V
Meter B: S=20kΩ/V, range=10V
a)
b)
c)
d)
Calculate voltage across resistor R B without any voltmeter is connected.
Calculate voltage across resistor R B with voltmeter A is used.
Calculate voltage across resistor R B with voltmeter B is used.
Determine the percentage of error of the reading of each voltmeter due to voltmeter
insertion.
7. In the circuit below, what is the value Rx if the meter reads half-scale?
Rz =4.6 kΩ
Ifs = 50uA
Rm = 2kΩ
R = 1kΩ
Rsh = 500Ω
E=1.5V
Rx