B&K 2704C Operating Instructions
OPERATING INSTRUCTIONS
MODEL 2704C
DIGITAL MULTIMETER
10A
COM
mA
V
V
F
A
A
2704C
Hz V
SAFETY INFORMATION
The following safety information must be observed to ensure maximum personal
safety during the operation at this meter:
Use the meter only as specified in this manual or the protection provided by the
meter might be impaired.
Test the meter on a known voltage before using it to determine if hazardous
voltage is present.
Do not use the meter if the meter or test leads look damaged, or if you suspect
that the meter is not operating properly.
Never ground yourself when taking electrical measurements. Do not touch
exposed metal pipes, outlets, fixtures, etc., which might be at ground potential.
Keep your body isolated from ground by using dry clothing, rubber shoes, rubber
mats, or any approved insulating material.
Turn off power to the circuit under test before cutting, unsoldering, or breaking
the circuit. Small amounts of current can be dangerous.
Use caution when working above 60V dc or 30V ac rms. Such voltages pose a
shock hazard.
When using the probes, keep your fingers behind the finger guards on the
probes.
Measuring voltage which exceeds the limits of the multimeter may damage the
meter and expose the operator to a shock hazard. Always recognize the meter
voltage limits as stated on the front of the meter.
SPECIFICATIONS
Display: 3½ digit liquid crystal display (LCD) with a maximum reading of 1999.
Polarity: Automatic, positive implied, negative polarity indication.
Overrange: (OL) or (-OL) is displayed.
Zero: Automatic.
Low battery indication: The "
" is displayed when the battery voltage drops
below the operating level.
Measurement rate: 2.5 times per second, nominal.
Operating environment: 0
℃ to 50℃ at < 70% relative humidity.
Storage temperature: -20
℃ to 60℃, 0 to 80% relative humidity.
Accuracy: Stated accuracy at 23
℃ ±5℃, < 75% relative humidity.
Temperature Coefficient: 0.1 x (specified accuracy) per
℃. (℃ to 18℃, 28℃ to
50
℃).
Altitude: 6562 feet (2000m).
Power: Single stand ard 9-volt battery, NEDA 1604, JIS 006P, IEC 6F22.
Battery life: 150 hours typical with carbon-zinc.
Dimensions: 165mm (H) x78mm (W) x42.5mm (D).
Weight: Approx. 10.0 oz.(285g) including holster.
Accessories: One set test leads, one spare fuse, 9V battery (installed), and
Operating Instructions.
DC VOLTS
Ranges: 200mV, 2V, 20V, 200V, 1000V
Resolution: 0.1mV
Accuracy: ± ( 0.8% rdg + 1 dgt)
Input impedance: 10M
Ω
Overload protection: 1000VDC or 750VAC rms
600VDC/AC rms 15 seconds on 200mV range
AC VOLTS
(50Hz - 500Hz)
Ranges: 200mV, 2V, 20V, 200V, 750V
Resolution: 0.1mV
Accuracy:
± ( 1.5% rdg + 5 dgts) on 200mV to 20V ranges
± ( 2.0% rdg + 5 dgts) on 200V,750V ranges
Input impedance:
10M
Ω
Overload protection: 1000VDC or 750VAC rms
600VDC/AC rms 15 seconds on 200mV range
CURRENT
DC Ranges: 20mA, 200mA, 10A
DC Resolution: 10uA
DC Accuracy:
± ( 1.0% rdg + 1 dgts) on 20mA to 200mA ranges
± ( 3.0% rdg + 3 dgts) on 10A range
DC Input protection: 0.5A/500V fast blow ceramic fuse
10A/600V fast blow ceramic fuse
AC Ranges: 20mA, 200mA, 10A (50Hz ~ 500Hz)
AC Resolution: 10uA
AC Accuracy:
± ( 2.0% rdg + 5dgts) on 20mA to 200mA ranges
± ( 3.5% rdg + 5 dgts) on 10A range
AC Input protection: 0.5A/500V fast blow ceramic fuse
10A/600V fast blow ceramic fuse
10A AC & DC
Input : 10A for 60 seconds maximum followed
by a 10 minute cooling period
RESISTANCE
Ranges: 200
Ω, 2kΩ200kΩ, 20MΩ, 2000MΩ
Resolution: 0.1
Ω
Accuracy:
± ( 1.0% rdg + 4 dgts) on 200
Ωto 200kΩranges
± ( 2.0% rdg + 4 dgts) on 20M
Ωrange
± [ (5.0% rdg - 10 dgts) +10dgts] on 2000M
Ωrange
Open circuit volts: 0.3Vdc (3.0Vdc on 200
Ω, 2000MΩranges)
Overload protection: 500VDC or AC rms
CONTINUITY
Audible indication: Less than 100
Ω
Response time: 100ms
Overload protection: 500VDC or AC rms
DIODE TEST
Test current: Approx. 1.0mA
Accuracy: ±(1.5% rdg + 3dgts)
Open circuit volts: 3.0Vdc typical
Overload protection: 500VDC or AC rms
CAPACITANCE
Ranges: 2nF, 20nF, 200nF, 2uF, 20uF
Resolution: 1PF
Accuracy: ±(4% rdg + 10 dgts)
Discharge capacitor before connecting
TRANSISTOR hFE
Range: 0 ~ 1000
Base current: 10uAdc approx. (Vdc = 3.0Vdc)
FREQUENCY
(Autoranging)
Ranges: 2kHz, 20kHz, 200kHz, 2MHz,20MHz
Resolution: 1Hz
Accuracy: ±(0.1% rdg + 3 dgts)
Sensitivity: 2.0V RMS min
Minimum pulse width: 25ns
Duty cycle limits: >30% and <70%
Overload protection: 500VDC or AC rms
LOGIC TEST
Threshold: Logic Hi (2.8 ±0.8V)
Logic Lo (0.8 ±0.5V)
Indication: 40 msec beep at logic low
Overload protection: 500VDC or AC rms
OPERATION
Before taking any measurements, read the Safety Information Section. Always
examine the instrument for damage, contamination (excessive dirt, grease, etc.)
and defects. Examine the test leads for cracked or frayed insulation. If any
abnormal conditions exist do not attempt to make any measurements.
Input Warning Beeper
The meter has a beeper that warns the user when the test lead is in the current
jack while the meter is switched to make a voltage measurement. Another safety
feature to protect the meter and you.
Data Hold
Press [HOLD] button to lock the reading on display, and release it by pressing
the button again
.
MAX/MIN
Press MAX/MIN once begins recording MIN and MAX.
Press MAX/MIN to select current reading MIN or MAX.
Hold
down for 2 seconds to exit MAX/MIN function.
Voltage Measurements
1.Connect the red test lead to ”V
Ω” jack and the black test lead to the ”COM”
jack.
2.Set the Function/Range switch to the desired voltage type (AC or DC) and
range. If magnitude of voltage is not known, set switch to the highest range
and reduce until a satisfactory reading is obtained.
3.Connect the test leads to the device or circuit being measured.
4. For dc, a (-) sign is displayed for negative polarity; positive polarity is implied.
Current Measurements
1.Connect the red test lead to the ( mA or 10A) jack and the black test lead to the
“COM” jack.
2.Set the Function/Range switch to the DC or AC ranges.
3.Remove power from the circuit under test and open the normal circuit path
where the measurement is to be taken. Connect the meter in series with the
circuit.
4.Apply power and read the value from the display.
Resistance and Continuity Measurements
1.Set the Function/Range switch to the desired resistance range or continuity
position.
2.Remove power from the equipment under test.
3.Connect the red test lead to the “ V
Ω” jack and the black test lead to
the ”C O M ” jack.
4.Touch the probes to the test points. In ohms, the value indicated in the display
is the measured value of resistance. In continuity test, the beeper sounds
continuously, if the resistance is less than 100
Ω.
Note when using 2000M
ΩRange
The 2000M
Ωrange has a fixed 10-count offset in the reading. When the test
leads are shorted together in this range, the meter will display 010. This residual
reading must be subtracted from the reading. For example, when measuring
1100M
Ωon the 2000MΩrange, the display will read 1100, from which the 10
residual is subtracted to obtain the actual resistance of 1100M
Ω.
Diode Tests
1.Connect the red test lead to the “ V
Ω” jack and the black test lead to
the ”C O M ” jack.
2.Set the Function/Range switch to the “
“ position.
3.Turn off power to the circuit under test.
4.Touch probes to the diode. A forward-voltage drop is about 0.6V (typical for a
silicon diode).
5.Reverse probes. If the diode is good, “OL” is displayed. If the diode is shorted,
“000” or another number is displayed.
6. If the diode is open, “OL” is displayed in both directions.
Capacitance Measurements
1.Set the Function/Range switch to the desired F (capacitance) range.
2.Never apply an external voltage to the Cx sockets.
Damage to the meter rnay result.
3.Insert the capacitor directly into the Cx sockets.
4.Read the capacitance directly from the display.
Transistor hFE Measurements
1.Set the Function/Range switch to the desired hFE range (PNP or NPN type
transistor).
2.Never apply an external voltage to the hFE sockets.
Damage to the meter may result.
3.Plug the transistor directly into the hFE sockets. The sockets are labeled E, B,
and C for emitter, base, and collector.
4.Read the transistor hFE directly from the display.
Frequency
Measurements
1.Set the Function/Range switch to the ”Hz” position.
2.Connect the red test lead to the “V
Ω” jack and the black test lead to the ”COM”
jack.
3.Connect the test leads to the point of measurement and read the frequency
from the display.
Logic Measurements
1.Set the Function/Range switch to the “LOGIC” position.
2.Connect the red test lead to “V
Ω” jack and the black test lead to the ”C O M ”
jack.
3.Connect the red test lead to the test point and the black lead to the common
buss of the logic circuit.
4. A “
▲”
on the display indicates TTL logic high and a “
▼”indicates a TTL logic
low. Both indicators are on when the point of measurement is toggling high
and low.
MAINTENANCE
WARNING
Remove test leads before changing battery or fuse or
performing any servicing.
Battery Replacement
Power is supplied by a 9 volt battery. (NEDA 1604, IEC 6F22). The "
" appears
on the LCD display when replacement is needed. To replace the battery, remove
the three screws from the back of the meter and lift off the front case. Remove
the battery from case bottom.
Fuse Replacement
If no current measurements are possible. Check for a blown overload protection
fuse. For access to fuses, remove the three screws from the back of the meter
and lift off the front case. Replace F1 only with the original type 0.5A/500V, fast
acting ceramic fuse, 6.35x32mm .
Replace F2 only with the original type 10A/600V, fast acting ceramic fuse,
6.35x25.4mm .
Cleaning
Wipe the case with a damp cloth and mild detergent. Do not use abrasives or
solvents. Dirt or moisture in the terminals can affect readings.
Safety: Conforms to IEC61010-1 (EN61010-1), CATII 1000V, CATIII 600V, Class
II, Pollution degree 2 Indoor use.
CATII: Is for measurements performed on circuits directly connected to the
low-voltage installation.
CAT III: Is for measurements performed in the building installation.
EMC: Conforms to EN61326.
The symbols used on this instrument are:
Caution, refer to accompanying documents
Equipment protected throughout by Double insulation (Class II)
Alternating current
Direct current
Ground