background image

-17-

RESISTANCE MEASUREMENTS

1) Connect the black test lead to the “COM” terminal.
2) Connect the red test lead to the “V

MA” terminal.

3) Set the range switch to the desired “

” position.

4) If the resistance being measured is connected to a circuit, turn off the power to the circuit being tested and

discharge all of the capacitors.

5) Connect the leads across the resistor to be measured and read the display.

When measuring high

resistance, be sure not to contact adjacent points even if insulated. Some insulators have relatively low
resistance and will cause the measured resistance to be lower than the actual resistance.

DIODE CHECK

1) Connect the black test lead to the “COM” terminal.
2) Connect the red test lead to the “V

MA” terminal.

3) If the diode being measured is connected to a circuit, turn off all power to the circuit and discharge all

capacitors.

4) Set the range switch to “       ”.

Forward Voltage Check
5) Connect the red lead to the anode and the black lead to the cathode of the diode. Normally the forward

voltage drop of a good silicon diode reads between 450 and 900mV.

Reverse Voltage Check
6) Reverse the leads to the diode. If the diode is good, an overrange indication is given (a 1 in the most

significant digit and blanks in the remaining digits). If the diode is bad, “000” or some other value is
displayed.

h

FE

MEASUREMENTS

1) Set the range switch to h

FE

and insert the test transistor into the appropriate NPN or PNP

holes in the transistor socket.

2) Read the h

FE

of the transistor.

BATTERY & FUSE REPLACEMENT

If “     ” appears on the display, it indicates that the battery should be replaced.
To replace battery and fuse (250mA/250V), remove the 2 screws in the bottom of the case.
Simply remove the old fuse/battery and replace with a new fuse/battery.

QUIZ

1. The function of the A/D converter is to . . .

A) convert digital to analog.
B) divide the analog signal by 2.
C) convert analog to digital.
D) convert AC to DC.

2. The divider used for DC voltage measurements is a . . .

A) divide by 20.
B) capacitance divider.
C) divide by 5.
D) resistor divider.

3. When the AC voltage is measured, it is first . . .

A) divided by 2.
B) rectified.
C) divided by 100.
D) sent to a high pass filter.

4. When measuring current, the shunt resistors convert the
current to . . .

A) –0.199 to +0.199 volts.
B) –1.199 to +1.199 volts.
C) –0.099 to +0.099 volts.
D) –199 to +199 volts.

5. The DC voltage divider resistors add up to . . .

A) 100

.

B) 1000

.

C) 100k

.

D) 1M

.

Answer

s:

1.C

, 2.

D, 3.

B, 4.

A,

5.D

, 6.

A, 7.B

, 8.

C, 9.

B, 10.

B

6. Resistance measurements are made by . . .

A) comparing voltage drops in the unknown resistor and a

reference resistor.

B) measuring the current in the unknown resistor.
C) measuring the current in the reference resistor.
D) equalizing the voltage drops in the unknown and the

reference resistors.

7. The measurement cycle performed by the A/D converter can be

divided into time periods known as . . .

A) long and short.
B) autozero, integrate and read.
C) zero, read and interphase.
D) convert, integrate and display.

8. A resistor with the band colors green-black-green-brown-green is . . .

A) 50.5k

+5%.

B) 5.15k

+10%.

C) 5.05k

+.5%.

D) 5.05k

+1%.

9. The M-1005K has . . .

A) A 3 digit display.
B) A 3 1/2 digit display.
C) A 4 1/2 digit display.
D) None of the above.

10.When measuring 450mA, the meter leads should be connected to . . .

A) COM and V

mA.

B) COM and 10A.
C) 10A and V

mA.

D) COM and Building GND.

+

Summary of Contents for M-1006K

Page 1: ...DIGITAL MULTIMETER KIT MODEL M 1006K Assembly and Instruction Manual Elenco Electronics Inc Copyright 2001 Elenco Electronics Inc 753096...

Page 2: ...ld 162200 1 R2 352k 5 1 2W orange green red orange green 163551 5 R18 R22 470k 5 1 4W yellow violet yellow gold 164700 1 R1 548k 5 1 2W green yellow gray orange green 165451 1 R23 1M 5 1 4W brown blac...

Page 3: ...nit 1 000 nano units 1 micro unit 1 000 milli units 1 unit 1 000 kilo units 1 kilo unit METRIC UNITS AND CONVERSIONS IDENTIFYING CAPACITOR VALUES Capacitors will be identified by their capacitance val...

Page 4: ...Component Lead Solder Soldering Iron Drag Foil 1 Solder all components from the copper foil side only Push the soldering iron tip against both the lead and the circuit board foil 2 Apply a small amou...

Page 5: ...W Resistor white brown black black brown see Figure A R14 4 7k 5 1 4W Resistor yellow violet red gold see Figure A R13 100 5 1 4W Resistor brown black brown gold see Figure A R19 470k 5 1 4W Resistor...

Page 6: ...e component side as shown in Figure D Adjust the wire so that it sticks out the other solder side of the PC board 3 16 of an inch Solder the wire to the PC board on the component side only Be sure tha...

Page 7: ...ver backing Place the LCD zebra frame and zebras into the top case as shown in Figure E Be sure that the LCD tab is in the same direction as shown in the figure Cut open the plastic envelope containin...

Page 8: ...Place the PC board over the selector knob Be sure that the 8 pin socket slides into its hole Then fasten the PC board with two 6mm screws as shown in Figure G Insert the 0 25A 250V fuse into the fuse...

Page 9: ...t wire so that there is less wire between the 10A DC and COM sockets If the meter reads low resolder the shunt wire so that there is more wire between the sockets 1 ACV Range 750 0 0 0 200 0 0 0 2 DCA...

Page 10: ...e following table Read the currents shown and compare to a known accurate meter If any of the above tests fail a Check the fuse b Check the value and soldering of resistors R7 R8 and R9 DC VOLTS TEST...

Page 11: ...ring of resistors R1 R6 and R12 hFE 1 Set the range switch to hFE and insert a small transistor into the appropriate NPN or PNP holes in the transistor socket 2 Read the hFE of the transistor The hFE...

Page 12: ...t is clocked at about two readings per second The digitized measurements are presented to the display as four decoded digits seven segments plus polarity The decimal point position on the display is d...

Page 13: ...switch closes This applies a known reference voltage to the input to the A D converter The polarity of this voltage is automatically selected to be opposite that of the unknown input voltage thus cau...

Page 14: ...erters One inverter shown for clarity 7 6 4 OSC 1 OSC 2 OSC 3 DIGITAL SECTION ANALOG SECTION of 7106 CREF RINT CAZ CINT INT CREF REF HI REF LO CREF BUFFER V 35 42 44 43 41 36 37 1 AUTO ZERO A Z Z1 A Z...

Page 15: ...alue required to give the correct RMS reading CURRENT MEASUREMENT Figure 6 shows a simplified diagram of the current measurement function Internal shunt resistors convert the current to between 0 199...

Page 16: ...mple series circuit is formed by the voltage source a reference resistor from the voltage divider selected by the selector switches and the test unknown resistor The ratio of the two resistors is equa...

Page 17: ...t known set the switch to the highest range 4 Connect the leads across the points to be measured and read the display If the range switch is too high reduce it until a satisfactory reading is obtained...

Page 18: ...lay it indicates that the battery should be replaced To replace battery and fuse 250mA 250V remove the 2 screws in the bottom of the case Simply remove the old fuse battery and replace with a new fuse...

Page 19: ...18 SCHEMATIC DIAGRAM...

Page 20: ...Elenco Electronics Inc 150 W Carpenter Avenue Wheeling IL 60090 847 541 3800 www elenco com e mail elenco elenco com...

Reviews: