Fluke 21 User manual

77/75/23/21 English Instruction Sheet
Page 1
®
77/75/23/21
Series III Multimeter
Instruction Sheet
WRead First: Safety Information
•Never use the meter if the meter or test leads look damaged.
•Be sure the test leads and switch are in the correct position for
the desired measurement.
•Never measure resistance in a circuit when power is applied.
•Never touch the probes to a voltage source when the test
leads are plugged into the 10 A or 300 mA input jack.
•Never apply more than the rated voltage between any input
jack and earth ground.
•Be careful when working with voltages above 60 V dc or 30 V
ac rms. Such voltages pose a shock hazard.
•Keep your fingers behind the finger guards on the test probes
when making measurements.
WWarning
To avoid false readings, which could lead to
possible electric shock or personal injury, replace
the battery as soon as the battery indicator (M)
appears.
Symbols
WRead First: Safety Information
YDangerous Voltage May Be Present
TDouble Insulation
Overvoltage Installation Category per IEC 1010:
CAT II
CAT III
Typical locations include; main wall outlets,
local appliances, and portable equipment.
Typical locations include switches in the fixed
installation and equipment for industrial use
permanently connected to the fixed installation.
PN 650512 August 1997 Rev.2, 7/98
1997, 1998 Fluke Corporation. All rights reserved. Printed in U.S.A.
All product names are trademarks of their respective companies

77/75/23/21 English Instruction Sheet
Page 2
Input Jacks
V
600V
1000V
FUSED
CAT
CAT
Volts, Ohms,
Diode Test
Common
Terminal
Amp
Milliamp
hc1f.eps
See Specifications for overload protection.
Autorange
The meter defaults to autorange when you turn on the meter.
Manual Range
Manual ranging is available in V ac, V dc, ohms, A ac, and A dc.
RANGE
CAT
CAT
+_
RANGE
MANUAL
MANUAL
Momentary
hc11f.eps
To return to autorange, press for 1 second or turn the
rotary switch.

77/75/23/21 English Instruction Sheet
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Automatic Touch Hold  Mode
WWarning
To avoid electric shock, do not use the Touch Hold
mode to determine if a circuit with high voltage is
dead. The Touch Holdmode will not capture
unstable or noisy readings.
The Touch Holdmode automatically captures and displays
stable readings for all functions.
Single Beep
RANGE
+__
RANGE
+_
RANGE
CAT
CAT
+
HOLD
HOLD
HOLD HOLD
AUTO
Momentary
HOLD
V V V
hc4f.eps
When the meter captures new input, it beeps and a new reading
is displayed.
Note
Stray voltages can produce a new reading.
To exit the Touch Holdmode, press momentarily or
turn the rotary switch.
Bar Graph
The bar graph shows readings relative to the full scale value of
the displayed measurement range and indicates polarity.
hc15f.eps

77/75/23/21 English Instruction Sheet
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Standby
If the meter is on but is inactive for an hour (20 minutes in diode
test), the display goes blank and displays four bar graph
segments. To resume operation, turn the rotary switch or press a
button.
AC and DC Voltage (KLmL)
RANGE
CAT
CAT
+__
RANGE
CAT
CAT
+_
RANGE
CAT
CAT
+
Volts AC Volts DC Millivolts DC
VVmV
hc3f.eps
Resistance (e)
Turn off the power and discharge all capacitors. An external
voltage across a component will give invalid resistance readings.
RANGE
CAT
CAT
+_
hc7f.eps

77/75/23/21 English Instruction Sheet
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Diode Test (G)
RANGE
CAT
+__
Forward Bias Single Beep
RANGE
CAT
CAT
+
Reverse Bias
_
RANGE
CAT
CAT
+
Shorted
Open and
Good Diode Good Diode
Bad Diode
_
RANGE
CAT
CAT
+
Bad Diode
hc5f.eps

77/75/23/21 English Instruction Sheet
Page 6
Continuity Test ( R)
RANGE
CAT
CAT
+_
RANGE
CAT
CAT
+_
hc8f.eps
If continuity exists (resistance < 210 Ωfor Models 21/75 and
<270 Ωfor Models 23/77), the beeper sounds continuously. The
meter beeps twice if it is in Touch Holdmode.
Current (?A)
WWarning
To avoid injury, do not attempt a current
measurement if the open circuit voltage exceeds the
rated voltage of the meter.
To avoid blowing an input fuse, use the 10 A jack until you are
sure that the current is less than 300 mA.
Turn off power to the circuit. Break the circuit. (For circuits of
more than 10 amps, use a current clamp.) Put the meter in series
with the circuit as shown and turn power on.
RANGE
_
CAT
CAT
+
+
1
2
4
3
A
hc10f.eps

77/75/23/21 English Instruction Sheet
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Probe Holder
hc14f.eps
Maintenance
WWarning
To avoid electric shock, remove the test leads
before opening the case, and close the case before
using the meter. To prevent fire and possible arc-
flash, use fuses with ratings shown on the back of
the meter.
Caution
To avoid contamination or static damage, do not
touch the circuit board without proper static
protection.
Internal Fuse Test
RANGE
10 A300 mA Ω
<.5
Ω
4-8 OKOK OK
OK
hc9f.eps

77/75/23/21 English Instruction Sheet
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Battery Replacement
Note
Before opening the case, make sure the test leads are
removed and the rotary switch is turned to OFF.
hc12f.eps
Fuse Replacement
F2
F2
F1
F1
23/77 21/75
hc13f.eps
Cleaning
To clean the meter, use a damp cloth and mild detergent; do not
use abrasives or solvents on the meter.

77/75/23/21 English Instruction Sheet
Page 9
Service and Parts
To contact Fluke, call one of the following telephone numbers:
USA and Canada: 1-888-99-FLUKE (1-888-993-5853)
Europe: [phone]
Japan: [phone]
Singapore: +65-*-276-6196
Anywhere in the world: [phone]
Or, visit Fluke’s Web site at www.fluke.com.
Item Description Fluke
PN Quan.
BT1 Battery, 9 V, NEDA 1604/IEC 6F22, or
NEDA 1604A/IEC 6LR61 696534 614487 1
F1* Models 21/75: Fuse, F630 mA, 250 V, Min Interrupt
Rating 1500 A or IEC 127-1 740670 1
F2* Fuse, F11 A, 1000 VAC/DC,
Min Interrupt Rating 17 kA 943118 1
F1* Models 23/77: Fuse, F44/100 A, 1000 VAC/DC,
Min Interrupt Rating 10 kA 943121 1
F2* Fuse, F11 A, 1000 VAC/DC,
Min Interrupt Rating 17 kA 943118 1
* For safety, use exact replacement
Specifications
Accuracy is specified for a period of one year after calibration, at
18°C to 28°C (64°F to 82°F) with relative humidity to 90%. AC
conversions are ac-coupled, average responding, and calibrated
to the RMS value of a sine wave input.
Accuracy specifications are given as:
±([% of reading] + [number of least significant digits])
Maximum Voltage Between
any Terminal and Earth
Ground
Rated voltage
Display Digital: 3,200 counts, updates 2.5/sec
Analog: 31 segments, updates 25/sec
Response Time of Digital
Display V ac < 2 s
V dc < 1 s
Ω< 1s to 320 kΩ, < 2s to 3.2 MΩ,
< 10 s to 32 MΩ
Operating Temperature 0°C to 50°C
Storage Temperature -40°C to 60°C
Temperature Coefficient 0.1 x (specified accuracy)/°C
(<18°C or >28°C)

77/75/23/21 English Instruction Sheet
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Electromagnetic Compatibility
In RF field of 3 V/m on all
functions.
Total accuracy = Specified accuracy
+ 0.1% of range.
Relative Humidity
except 32 MΩrange
32 MΩrange only
0% to 90% (0°C to 35°C)
0% to 70% (35°C to 50°C)
0% to 80% (0°C to 35°C)
0% to 70% (35°C to 50°C)
Altitude Operating: 2000 meters
Storage: 12,000 meters
Battery Type 9 V NEDA 1604 or 6F22 or 006P,
or NEDA 1604A or 6LR61
Battery Life 2000 hrs typical with alkaline
1600 hrs typical with carbon zinc
Continuity Beeper 4096 Hz
Shock, Vibration per MIL-T-PRF 28800F Class III,
Sinusoidal, Non Operating
Size (H x W x L) 3.7 cm x 8.9 - 7.8 cm x 19 cm
(1.5 in x 3.5 - 3.1 in x 7.49 in)
Weight 365 g (12.9 oz)
Safety Models 21/75 Series III: 600 V CAT III,
Models 23/77 Series III: 600 V CAT III
and 1000 V CAT II per ANSI/ISA
S82.01-1994, EN 61010-1: 1993, CSA
C22.2 No 1010.1-92, UL 3111-1.
EMC Regulations EN 61326-1 1997.
Certifications/Listings