Operation Manual
FK38 Series
Digital Multimeter
1.
Description
FK38 series meters are a series of battery-driven digital multimeters with high reliability
and high performance. The meters adopt 26mm LCD display with clear reading, unit
symbol display, overload protection functions, more convenient to use.
The series meters are mainly used to measure DC voltage, AC voltage, DC current, AC
current, resistance, capacitance, inductance, diode test, transistor hFE, continuity,
temperature and frequency etc.
2. Safety Information
FK38 series meters have been designed and tested in accordance of IEC publication
1010, Safety Requirement for Electronic Measuring Apparatus. READ SAFETY
INFORMATION FIRST before you do any operations.
2-1. Do not apply any measurements above 1000V DC or 750V AC, the measurements limits
on this meter, when using the meter to measure the voltages.
2-2. Always check whether test leads have been connected properly, well-insulated etc. to
avoid electrical shock hazard.
2-3. Always keep away from test points in switching of ranges or functions.
2-4. Avoid mistakable operations when switching between proper ranges or functions.
Although these series meters have been designed with full-range protection, due to
safety issues, please pay much attention.
2-5. Do not apply any measurements above 20A current when using the meter to measure the
current.
2-6. Safety Symbols:
“
” Dangerous Voltage.
“ ” GND
“ ” Double Insulation.
“ ” Operators must refer to manual.
“ ” Low Battery.
3. Specification
3-1. General Specification.
3-1-1. Display: LCD Display
3-1-2. Maximum Display: 1999(3 1/2 digit) automatic polarity display (FK381~FK385,
FK388), 19999 (4 1/2 digit) automatic polarity display (FK386~FK387).
3-1-3.
Measurements Method: Double integrating type A/D converting.
3-1-4.
Sampling Rate: 3/sec approximately.
3-1-5.
Maximum Common Mode Voltage: 500V DC/AC rms.
3-1-6.
Over-Range Display: “1” on highest digit bit.
3-1-7.
Low Battery Indication: “ ” is displayed when the battery drops below the
operating level.
3-1-8.
Operating Environment: 0~40°C at <80% relative humidity.
3-1-9.
Storage Environment: -10~50°C at <80% relative humidity.
3-1-10. Power: Single standard 9V battery (NEDA 1604/6F22 or equal model).
3-1-11. Dimensions: 190mm (D) x88.5mm (W) x27.5mm (H).
3-1-12. Weight: Approx. 240g including battery.
3-1-13.
Accessories: Operating Manual, 9V battery, one pair test leads, leather bag, antishock Holster, Color box.
3-2. Technology Specification:
3-2-1. Accuracy: r(% reading + No. of digits)
3-2-2. Performance (“Ⴃ” means this function is contained).
Model
Function
DC VOLTS
FK381
FK382
FK384
FK385
FK386
FK387
FK388
Ⴃ
Ⴃ
Ⴃ
Ⴃ
Ⴃ
Ⴃ
Ⴃ
AC VOLTS
Ⴃ
Ⴃ
Ⴃ
Ⴃ
Ⴃ
Ⴃ
Ⴃ
DC Current
Ⴃ
Ⴃ
Ⴃ
Ⴃ
Ⴃ
Ⴃ
Ⴃ
AC Currentt
Ⴃ
Ⴃ
Ⴃ
Ⴃ
Ⴃ
Ⴃ
Ⴃ
Resistance
Ⴃ
Ⴃ
Ⴃ
Ⴃ
Ⴃ
Ⴃ
Ⴃ
Diode Test &
Continuity
Transistor
Ⴃ
Ⴃ
Ⴃ
Ⴃ
Ⴃ
Ⴃ
Ⴃ
Ⴃ
Ⴃ
Ⴃ
Ⴃ
Ⴃ
Ⴃ
Ⴃ
Capacitance
Ⴃ
Ⴃ
Ⴃ
Ⴃ
Ⴃ
Ⴃ
Ⴃ
Ⴃ
Ⴃ
Temperature
ഒ or ഘ
Ⴃ
Frequency
Ⴃ
Inductance
Ⴃ
Ⴃ
Ⴃ
Ⴃ
Ⴃ
Ⴃ
Backlight
Ⴃ
3-2-3. Technology Parameters (“*” means this range is not available)
3-2-3-1. DC Voltages (DCV)
Accuracy
Model᧤3 1/2 digit᧥
Range
FK381
FK382
FK384
FK385
FK388
200mV
2V
s(0.5%᧧3d)
20V
200V
1000V
s(1.0%᧧5d)
Accuracy
Range
200mV
2V
20V
Model᧤4 1/2 digit᧥
FK386
FK387
s(0.05%᧧3d)
s(0.1%᧧3d)
Resolution
100uV
1mV
10mV
100mV
1V
Resolution
10uV
100uV
1mV
200V
1000V
s(0.1%᧧5d)
s(0.2%᧧5d)
10mV
100mV
Input Resistance: 10M: for all ranges.
Overload Protection: 250V DC or AC peak voltage in 200mV range, 1000V DC or AC peak
voltage for other ranges.
3-2-3-2. AC Voltage (ACV)
Accuracy
Resolutio
Model᧤3 1/2 digit᧥
Range
n
FK381
FK382
FK384
FK385
FK388
200mV
2V
20V
200V
750V
200mV
2V
s(1.2%᧧3)
s(1.2%᧧5d)
Model᧤4 1/2 digit᧥
FK386
FK387
Resolution
10uV
s(1.0%᧧25d)
s(0.8%᧧20d)
100uV
1mV
10mV
100mV
1V
s(0.8%᧧5d)
Accuracy
Range
*
s(1.2%᧧3)
s(0.8%᧧25d)
100uV
20V
200V
750V
s(1.0%᧧25d)
1mV
10mV
100mV
Input Resistance: 10M:, 1M: in 4 1/2 Digit.
Overload Protection: 250V DC or AC peak voltage in 200mV range, 1000V DC or AC peak
voltage in other ranges.
Frequency Range: 40~400Hz in ranges below 200V, 40~200Hz at 750V range.
Indication: Sine rms (mean value response).
3-2-3-3. DC Current (DCA)
Accuracy
Resolutio
Model᧤3 1/2Digit᧥
Range
n
FK385
FK381
FK382
FK384
FK388
200uA
*
*
0.1uA
2mA
1uA
*
s(0.8%᧧3d)
s(0.8%᧧3d)
20mA
*
10uA
200mA
100uA
s(1.2%᧧4d)
20A
s(2.0%᧧5d)
Accuracy
Range
Model᧤4 1/2 digit᧥
10mA
Resolution
FK386
2mA
20mA
200mA
FK387
s(0.5%᧧4d)
s(0.8%᧧6d)
0.1uA
1uA
10uA
20A
1mA
s(2.0%᧧15d)
Maximum Measurement Voltage Drop: 200mV
Maximum Input Current: 20A (Do not exceed 15s)
Overload Protection: 0.2A/250V fast blow ceramic fuse, no fuse in 20A range.
3-2-3-4. AC Current (ACA)
Accuracy
Model᧤3 1/2 digit᧥
Range
FK381
FK382
FK385
FK388
FK384
200uA
*
*
2mA
*
s(1.0%᧧5d)
s(1.0%᧧5d)
20mA
*
200mA
s(2.0%᧧5d)
0.1uA
1uA
20A
10mA
s(3.0%᧧10d)
Resolution
10uA
100uA
Accuracy
Range
Model᧤4 1/2 digit᧥
FK386
FK387
Resolution
200mA
s(1.2%᧧25d)
10uA
20A
s(2.5%᧧35d)
Maximum Measurements Voltage Drop: 200mV.
Maximum Input Current: 20A (Do not exceed 15s)
Overload Protection: 0.2A/250V fast blow ceramic fuse, no fuse in20A.
Frequency Range: 40~200Hz.
Indication: Sine rms (mean value response)
3-2-3-5. Resistance (:)
Accuracy
Model᧤3 1/2 digit᧥
Range
FK381
FK382
FK384
FK385
FK388
200˖
s(0.8%᧧5d)
2k˖
20k˖
200k˖
2M˖
1mA
Resolution
0.1˖
1˖
s(0.8%᧧3d)
10˖
100˖
1 k˖
s(1.0%᧧15d)
20M˖
200M˖
s[5%(Reading-10d)᧧20d]
*
2000M˖
Accuracy
Range
200˖
10 k˖
*
s[5%(Reading-10d)+20d]
Model᧤4 1/2 digit᧥
FK386
FK387
s(0.2%᧧10d)
s(0.5%᧧15d)
2 k˖
20 k˖
200 k˖
2M˖
100 k˖
1 M˖
Resolution
0.01˖
0.1˖
s(0.2%᧧5d)
s(0.5%᧧10d)
1˖
10˖
100˖
20M˖
s(0.5%᧧25d)
s(1.0%᧧35d)
1 k˖
Open Circuit Voltage: < 3V.
Overload Protection: 250V DC or AC peak voltage.
Cautions: a. Short test leads and get the measurement value of wire then reduce the value
after measuring the target when using 200Mȍ range. b. When using 200Mȍ, short test leads
the reading will be 1.0Mȍ, this doesn’t affect measuring accuracy, reduce this value in the
real measuring. eg. If the being measured resistance is 100Mȍ, the reading will be 101.0Mȍ,
the correct value equals the value after reading reduce short circuit resistance, 101.01.0=100.0Mȍ.
3-2-3-6. Capacitance
Accuracy
Range
FK381
2nF
*
20nF
*
200nF
*
2uF
*
20uF
200uF
Accuracy
Range
2nF
Model᧤3 1/2 digit᧥
FK382
FK384
FK385
FK388
*
s(2.5%᧧20d)
*
s(5%᧧5d)
Model᧤4 1/2 digit᧥
FK386
FK387
s(2 5%᧧50d)
Resolution
1pF
10pF
100pF
1nF
10nF
100nF
Resolution
0.1pF
20nF
200nF
2uF
20uF
Overload Protection: 36V DC or AC peak voltage.
3-2-3-7. DIODE Test and Continuity
Model
Range
Indication
Diode voltage drop
FK38 Series
Beeper buzzes,
measuring point
1pF
10pF
100pF
1nF
Test Conditions
Current approx.
1mA,Inverse
Voltage approx.
3V
Open Circuit
Voltage approx.
3V
resistance<50˖
Overload Protection: 250V DC or AC peak voltage.
WARNING: DO NOT INPUT VOLTAGES IN THE RANGE DUE TO SAFETY.
3-2-3-8. Temperature
Accuracy
Range
Model (3 1/2 digit)
FK384
FK385
FK388
Resolution
-40ഒ~1000ഒ
s(0.75%᧧3d)᧸400ഒ
1ഒ
s(1.5%᧧15d)ุ400ഒ
-40ഘ~1832 ഘ
s(0.75%᧧5d)᧸450ഘ
*
s(1.5%᧧15d)ุ450ഘ
Sensor: Ni-Cr or Ni-Si Thermocouple.
3-2-3-9. Frequencies.
Accuracy
Model᧤3 1/2 digit᧥
Range
FK384
FK385
FK388 (FREQ)
2kHZ
*
20kHZ
200kHZ
s(0.5%᧧4d)
s(1.5%᧧15d)
2MHZ
20MHZ
1oF
Resolution
1HZ
10HZ
100HZ
*
Accuracy
Range
Model᧤4 1/2 digit᧥
FK386
FK387
20 kHZ
s(1.5%᧧25d)
1kHZ
10kHZ
Resolution
1HZ
3-2-3-10. Transistor Parameters Test (hFE).
Model
Range
Indication
FK38 Series
NPN or PNP
0~1000
3-2-3-11. Inductance (L).
Accuracy
Range
Measuring Condition
Base Current Approx.
10uA.Vce Approx. 3V
Model᧤4 1/2 digit᧥
FK385
FK388
2mH
20mH
200mH
s(2.5%᧧20d)
2H
20H
Overload Protection: 36V DC or AC peak voltage.
4. Operating Instructions:
4-1. Operating Panel Instructions.
1. LCD Display: number and unit will display on it.
2. DC/AC Switch.
3. Meter Model.
4. Transistor Socket.
5. Juggle: switch functions and ranges.
6. Voltage, Resistance, Frequency and Temperature “+” socket.
Resolution
1uH
10uH
100uH
1mH
10mH
7.
8.
9.
10.
11.
12.
Common GND.
<200mA current testing and temperature “-” socket.
20A current testing socket.
Capacitance, inductance sockets.
Power ON/OFF: Turn on or turn off power.
Hold Button: When pressing this button, current number will remain on the LCD
display, symbol displays“ + ” on the LCD at the same time, press again, Remaining
function is disabled and “ + ” disappears.
4-2. Measuring DC Voltage.
4-2-1. Insert black test lead to “COM” jack, red test lead to “V/:” jack.
4-2-2. Set Range switch to desired DC range, then connect test leads to the circuit being
measured, the measurement point voltage of red test lead will display on the LCD
display.
CAUTIONS:
1. If you don’t know the range before measuring, switch range to the maximum range, and
then switch corresponding range according the indication.
2. If the highest digit bit displays “1”, which means it’s out of range, set Range switch to a
higher range.
Input DC should be below 1000V, it might damage the meter when exceeding
3.
maximum limits.
4. Avoid touching high-energy circuit when measuring high voltage circuit.
4-3. Measuring AC Voltage.
4-3-1. Insert black test lead to “COM” jack, red test lead to “V/:” jack.
4-3-2. Set Range switch to desired AC range, then connect test leads to the circuit being
measured, (press DC/AC switch when using FK385, FK388).
CAUTIONS:
1. If you don’t know the range before measuring, switch range to the maximum range,
then switch corresponding range according the indication.
2. If the highest digit bit displays “1”, which means it’s out of range, set Range switch to a
higher range.
3. Input AC should be below 750Vrms, it might damage the meter when exceeding
maximum limits.
4. Avoid touching high-energy circuit when measuring high voltage circuit.
4-4. Measuring DC Current.
4-4-1. Insert black test lead to “COM” jack, red test lead to “mA” jack (Maximum 200mA),
or red test lead to “20A” jack (Maximum 20A).
4-4-2. Set Range switch to desired DCA range, then connect test leads to the circuit being
measured.
CAUTIONS:
1. If you don’t know the range before measuring, switch range to the maximum range,
then switch corresponding range according the indication.
2. If the highest digit bit displays “1”, which means it’s out of range, set Range switch to a
higher range.
3.
Maximum input current is 200mA or 20A (according to the jack of red test lead),
overload current will blow the fuse, be cautious when doing measurement in 20A range,
overload current might heat the meter or damage it cause of no overload protection in
the range.
4-5. Measuring AC Current.
4-5-1. Insert black test lead to “COM” jack, red test lead to “mA” jack (Maximum 200mA),
or red test lead to “20A” jack (Maximum 20A).
4-5-2. Set Range switch to desired ACA range, then connect test leads to the circuit being
measured.
CAUTIONS:
1. If you don’t know the range before measuring, switch range to the maximum range, then
switch corresponding range according the indication.
2. If the highest digit bit displays “1”,which means it’s out of range, set Range switch to a
higher range.
3.
Maximum input current is 200mA or 20A (according to the jack of red test lead),
overload current will blow the fuse, be cautious when doing measurement in 20A range,
overload current might heat the meter or damage it cause of no overload protection in the
range
4-6. Measuring Resistance.
4-6-1. Insert black test lead to “COM” jack, red test lead to “V/:”.
4-6-2. Set Range switch to desired resistance range, then connect test leads to the circuit
being measured.
CAUTIONS:
1. It will display “1” on LCD if the resistance value is out of range, set Range switch to a
higher range in this situation; when the value of being-measured resistance is above
1Mȍ, it takes several seconds for the reading to get stable, it’s normal in resistance
measurement.
2. When input point is open circuit, the display is same as overload situation.
3. When measuring resistance in a circuit, make sure all powers have been turned off and
all capacitances have been charge-released.
4.
Never input voltage in resistance ranges, it’s definitely forbidden, although there’s
voltage protection in these ranges
4-7. Measuring Capacitance.
Insert capacitance to the capacitance socket and set Range switch to desired range.
CAUTIONS:
1. It will display “1” on LCD if the capacitance value is out of range, set Range switch to a
higher range in this situation.
2. Before inserting the capacitance to the capacitance socket, the reading of LCD might not
be “0”, remaining reading will become “0” gradually, and it won’t affect the
measurement accuracy in this situation.
3. Unit 1ȝF=1000nF; 1nF=1000pF
4.
Release capacitance charge before measurement to avoid any damages to the meter
4-8. Transistor hFE.
4-8-1. Set Range switch to hFE rank.
4-8-2. Judge NPN or PNP type, plug transistor to the hFE sockets, which are labeled E, B
and C for emitter, base and collector.
4-9. DIODE Test.
4-9-1. Insert black test lead to “COM” jack, red test lead to “V/:” jack (red test lead polarity
is “+”).
4-9-2. Set Range switch to
rank, connect test leads to the diode being measured,
the reading is the approximate value of diode voltage drop.
4-9-3. Connect test leads to the measurement points of being-measured circuit, if the internal
beeper buzzes, the resistance between measurement points is below 50ȍ.
4-10. Measuring Frequency.
4-10-1. Insert test leads or shielded wire to “COM” and “V/:” jacks.
4-10-2. Set Range switch to desired range, connect test leads to signal source or beingmeasured load.
CAUTIONS:
1. When input is over 10Vrms, the reading might be over accuracy.
2. Under noisy circumstance, better choose shielded wire for low output signal measuring.
3. When measuring high voltage circuit, avoid touching the circuit.
Never input over 250V DC or AC peak voltage to avoid damaging the meter.
4.
4-11. Measuring Temperature.
When measuring temperature, insert thermocouple cool point (free point) to temperature
measuring jack, black is “-“, red is “+”, thermocouple working point (temperature measuring
point) to the face or inside of being-measured object. Read the number directly from the
LCD display, reading is Centigrade or Fahrenheit.
4-12. Measuring Inductance.
Insert inductance to the inductance jacks, set Range switch to desired inductance range.
CAUTIONS: If the inductance is over range, the LCD display will display “1”, in this
situation switch range to a higher rank.
4-13. Data Hold
Press Data Hold switch, current data will remain on the display (peak value for JT388)
4-14. Automatic Power-Off.
The meter will automatically turn off power and switch to stand-by status if there’s no
operation in 15 minutes, the stand-by current is approximate 10µA. To restart the meter,
press POWER button twice (only for FK384, FK386, FK387).
5. Maintenance.
These series meters are exact meters, do not make any change to the circuits.
CAUTIONS:
5-1. Do not apply 1000V DC or 750V AC rms on this meter.
5-2. Do not measure voltage when function is in : rank.
5-3. Do not use this meter to do any measurements when back is not properly covered or
batter is not properly installed.
5-4. Remove test leads from testing point and turn OFF meter when replacing battery or fuse.
5-4-1. Battery should be replaced when LCD displays “ ” symbols.
Replacement Instructions:
5-4-1-1. Remove the screws from the back of meter and lift off battery door.
5-4-1-2. Remove battery and replace it with a 9V battery, although any standard 9V battery
is available, for long term using, you’d better choose alkali-battery.
5-4-1-3. Install battery door and tighten screws.
5-4-2. Fuse Replacement.
When replacing fuse, please use fuse with same specification.
This Instruction Manual is subject to modification without notice.
We believe that the content of the Instructions is correct. In case users find
any mistake or omission, please contact with the distributor.
This Company shall not take any responsibility for any accident or harm
due to improper operation of users.
Any function explained in this Instructions shall not justify the special use
of this Product.