| Fluke 120B Series Specifications |
| Oscilloscope mode |
| Vertical |
Frequency response - dc
coupled |
Without probes and test leads
(with BB120) |
123B: dc to 20 MHz (-3 dB)
124B and 125B: dc to 40 MHz (-3
dB) |
With STL120-IV 1:1 shielded test
leads |
DC to 12.5 MHz (-3 dB) / dc to 20
MHz (-6 dB) |
| With VP41 10:1 Probe |
123B: dc to 20MHz (-3 dB)
124B and 125B: dc to 40 MHz (-3
dB) |
Frequency response - ac
coupled (lf roll off) |
Without probes and test leads |
<10 Hz (-3 dB) |
With STL120-IV 1:1 shielded test
leads |
<10 Hz (-3 dB) |
| With VP41 10:1 Probe |
<10 Hz (-3 dB) |
Rise time, excluding probes,
test leads |
123B <17.5 ns
124B and 125B <8.75 ns |
| Input impedance |
Without probes and test
leads |
1 MΩ//20 pF |
| With BB120 |
1 MΩ//24 pF |
With STL120-IV 1:1 shielded test
leads |
1 MΩ//230 pF |
| With VP41 10:1 Probe |
5 MΩ//15.5 pF |
| Sensitivity |
5 mV to 200 V/div |
| Analog bandwidth limiter |
10 kHz |
| Display modes |
A, -A, B, -B |
| Max. input voltage A and B |
Direct, with test leads, or with
VP41 Probe |
600 Vrms Cat IV, 750 Vrms
maximum voltage. |
| With BB120 |
600 Vrms |
Max. floating voltage, from any
terminal to ground |
600 Vrms Cat IV, 750 Vrms up to 400Hz |
| Horizontal |
| Scope modes |
Normal, Single, Roll |
| Ranges (normal) |
Equivalent sampling |
123B: 20 ns to 500 ns/div,
124B and 125B: 10 ns to 500
ns/div |
| Real time sampling |
1 µs to 5 s/div |
| Single (real time) |
1 µs to 5 s/div |
| Roll (real time) |
1s to 60 s/div |
Sampling rate (for both
channels simultaneously) |
Equivalent sampling (repetitive
signals) |
Up to 4 GS/s |
Real time sampling 1 µs to 60
s/div |
40 MS/s |
| Trigger |
| Screen update |
Free run, on trigger |
| Source |
A, B |
| Sensitivity A and B |
@ DC to 5 MHz |
0.5 divisions or 5 mV |
| @ 40 MHz |
123B: 4 divisions
124B and 125B: 1.5 divisions |
| @ 60 MHz |
123B: N/A
124B and 125B: 4 divisions |
| Slope |
Positive, negative |
| Advanced scope functions |
| Display modes |
Normal |
Captures up to 25 ns glitches and
displays analog-like persistence
waveform |
| Smooth |
Suppresses noise from a waveform |
| Glitch off |
Does not capture glitches between
samples |
| Envelope |
Records and displays the minimum
and maximum of waveforms over
time |
| Auto set (Connect-and-View™) |
Continuous fully automatic adjustments of amplitude, time base, trigger
evels, trigger gap, and hold-off. Manual override by user adjustment of
amplitude, time base, or trigger level. |
| Dual input meter |
| The accuracy of all measurements is within ±(% of reading + number of counts) from 18 °C to 28 °C. |
Add 0.1x (specific accuracy) for each °C below 18 °C or above 28 °C. For voltage measurements with 10:1
probe, add probe uncertainty +1%. More than one waveform period must be visible on the screen. |
| Input A and input B |
| DC voltage (VDC) |
| Ranges |
500 mV, 5 V, 50 V, 500 V, 750 V |
| Accuracy |
±(0.5% +5 counts) |
Common mode rejection
(CMRR) |
>100 dB @ dc, >60 dB @ 50, 60, or 400 Hz |
| Full scale reading |
5000 counts |
| True-rms voltages (V ac and V ac+dc) |
| Ranges |
500 mV, 5 V, 50 V, 500 V, 750 V |
Accuracy for 5% to 100% of range
(DC coupled) |
DC to 60 Hz (V ac+dc) |
±(1% +10 counts) |
| 1 Hz to 60 Hz (V ac) |
±(1% +10 counts) |
Accuracy for 5% to 100% of range
(AC or dc coupled) |
60 Hz to 20 kHz |
±(2.5% +15 counts) |
| DC rejection (only VAC) |
>50 dB |
Common mode rejection
(CMRR) |
>100 dB @ dc |
| >60 dB @ 50, 60, or 400 Hz |
| Full scale reading |
5000 counts, reading is independent of any signal crest factor. |
| Peak |
| Modes |
Max peak, Min peak, or pk-to-pk |
| Ranges |
500 mV, 5 V, 50 V, 500 V, 2200 V |
| Accuracy |
Accuracy Max peak or Min peak |
5% of full scale |
| Accuracy Peak-to-Peak |
10% of full scale |
| Full scale reading |
500 counts |
| Frequency (Hz) |
| Ranges |
123B: 1 Hz, 10 Hz, 100 Hz, 1 kHz, 10 kHz, 100 kHz,1 MHz, 10 MHz,
and 50 MHz |
124B and 125B: 1 Hz, 10 Hz, 100 Hz, 1 kHz, 10 kHz, 100 kHz, 1 MHz,
10 MHz, and 70 MHz |
| Frequency range |
15 Hz (1 Hz) to 50 MHz in continuous autoset |
| Accuracy @1 Hz to 1 MHz |
±(0.5% +2 counts) |
| Full scale reading |
10,000 counts |
| RPM |
| Max reading |
50.00 kRPM |
| Accuracy |
±(0.5% +2 counts) |
| Duty cycle (PULSE) |
| Range |
2% to 98% |
| Frequency range |
15 Hz (1 Hz) to 30 MHz in continuous autoset |
| Pulse width (PULSE) |
| Frequency range |
15 Hz (1 Hz) to 30 MHz in continuous autoset |
| Full scale reading |
1000 counts |
| Amperes (AMP) |
| With current clamp |
Ranges |
Same as V dc, V ac, V ac+dc, or
PEAK |
| Scale factors |
0.1 mV/A, 1 mV/A, 10 mV/A, 100
mV/A, 400 mV/A, 1 V/A, 10
mV/mA |
| Accuracy |
Same as V dc, V ac, V ac+dc, or
PEAK (add current clamp
uncertainty) |
| Temperature (TEMP) with optional temperature probe |
| Range |
200 °C/div (200 °F/div) |
| Scale factor |
1 mV/°C and 1 mV/°F |
| Accuracy |
As V dc (add temp. probe uncertainty) |
| Decibel (dB) |
| 0 dBV |
1 V |
| 0 dBm (600 Ω /50 Ω) |
1 mW referenced to 600 Ω or 50 Ω |
| dB on |
V dc, V ac, or Vac+dc |
| Full scale reading |
1000 counts |
| Crest factor (CREST) |
| Range |
1 to 10 |
| Full scale reading |
90 Counts |
| Phase |
| Modes |
A to B, B to A |
| Range |
0 to 359 degrees |
| Resolution |
1 degree |
| Power (125B only) |
| Configurations |
1 phase / 3 phase 3 conductor balanced loads (3 phase: fundamental
component only, AUTOSET mode only) |
| Power factor (PF) |
Ratio between watts and VA range - 0.00 to 1.00 |
| Watt |
RMS reading of multiplying corresponding samples of input A (volts)
and input B (amperes) |
| Full scale reading |
999 counts |
| VA |
Vrms x Arms |
| Full scale reading |
999 counts |
| VA reactive (var) |
v((VA)2-W2) |
| Full scale reading |
999 counts |
| Vpwm |
| Purpose |
To measure on pulse width modulated signals, like motor drive inverter
outputs |
| Principle |
Readings show the effective voltage based on the average value of
samples over a whole number of periods of the fundamental frequency |
| Accuracy |
As Vrms for sinewave signals |
| Input A to common |
| Ohm (Ω) |
| Ranges |
123B and 124B |
500 Ω , 5 kΩ, 50 kΩ, 500 kΩ, 5 MΩ, 30 MΩ |
| 125B |
50 Ω, 500 Ω , 5 kΩ, 50 kΩ, 500 kΩ, 5 MΩ, 30 MΩ |
| Accuracy |
±(0.6% + 5 counts) 50 Ω ±(2% + 20 counts) |
| Full scale reading |
50 O to 5 MΩ - 5000 counts, 30 MΩ - 3000 counts |
| Measurement current |
0.5 mA to 50 nA, decreases with increasing ranges |
| Open circuit voltage |
<4 V |
| Continuity (Cont) |
| Beep |
<(30 O ±5 Ω ) in 50 Ω range |
| Measurement current |
0.5 mA |
| Detection of shorts of |
=1 ms |
| Diode |
| Measurement voltage |
@0.5 mA |
>2.8 V |
| @open circuit |
<4 V |
| Measurement current |
0.5 mA |
| Polarity |
+ on input A, - on COM |
| Capacitance (CAP) |
| Ranges |
50 nF, 500 nF, 5 µF, 50 µF, 500 µF |
| Full scale reading |
5000 counts |
| Measurement current |
500 nA to 0.5 mA, increases with increasing ranges |
| Advanced meter functions |
| Zero Set |
Set actual value to reference |
| AutoHold (on A) |
Captures and freezes a stable measurement result. Beeps when stable.
AutoHold works on the main meter reading, with thresholds of 1 Vpp
for AC signals and 100 mV for DC signals. |
| Fixed decimal point |
Activated by using attenuation keys |
| Cursor Readout (124B and 125B) |
| Sources |
A, B |
| Single vertical line |
Average, min and max readout |
Average, min, max and time from start of readout (in ROLL mode;
instrument in HOLD) |
Min, max and time from start of readout (in RECORDER mode;
instrument in HOLD) |
| Harmonics values in POWER QUALITY mode. |
| Dual vertical lines |
Peak-peak, time distance and reciprocal time distance readout |
| Average, min, max and time distance readout (in ROLL mode; instrument in HOLD) |
| Dual horizontal lines |
High, low and peak-peak readout |
| Rise or fall time |
Transition time, 0%-level and 100%-level readout (manual or auto
leveling; auto leveling only
possible in single channel mode) |
| Accuracy |
As oscilloscope accuracy |
| Recorder |
The recorder captures meter readings in Meter Recorder mode or continuously captures waveform samples
in Scope Recorder mode. The information is stored on internal memory or on optional SD card (with the
125B or 124B). |
The results are displayed as Chart recorder display that plots a graph of min and max values of Meter
measurements over time or as a waveform recorder display that plots all the captured samples. |
| Meter readings |
| Measurement Speed |
Maximum 2 measurement/s |
| Record Size (min, max, average) |
2 M readings for 1 channel |
| Recorded Time Span |
2 weeks |
| Maximum number of events |
1024 |
| Waveform record |
| Maximum sample rate |
400 K sample/s |
| Size Internal memory |
400 M samples Recorded Time |
| Span internal memory |
15 minutes at 500 µs/div
11 hours at 20 ms/div |
| Record Size SD card |
1.5 G samples |
| Recorded Time Span SD card |
11 hours at 500 µs/div
14 days at 20 ms/div |
| Maximum number of events |
64 |
| Power Quality (125B only) |
| Readings |
Watt, VA, var, PF, DPF, Hz |
| Watt, VA, var ranges (auto) |
250 W to 250 MW, 625 MW, 1.56 GW |
| When selected: total (% r) |
±(2% + 6 counts) |
| When selected: fundamental (% f) |
±(4% + 4 counts) |
| DPF |
0.00 to 1.00 |
| PF |
0.00 to 1.00, ±0.04 |
| Frequency range |
10.0 Hz to 15.0 kHz
40.0 Hz to 70.0 Hz |
| Number of Harmonics |
DC to 51 |
Readings / Cursor readings
(fundamental 40 Hz to 70 Hz) |
Vrms / Arms /Watt |
Each harmonic from fundamental
maybe selected for individual
readings |
| Includes frequency of fundamental, phase Angle and K-factor (in Amp and Watt) |
| BusHealth tester (Fluke 125B only) |
| Type |
Subtype |
Protocol |
| AS-i |
NEN-EN50295 |
| CAN |
ISO-11898 |
| Interbus S |
RS-422 |
EIA-422 |
| Modbus |
RS-232 |
RS-232/EIA-232 |
| RS-485 |
RS-485/EIA-485 |
| Foundation Fieldbus |
H1 |
61158 type 1, 31.25 kBit |
| Profibus |
DP |
EIA-485 |
| PA |
61158 type 1 |
| Miscellaneous |
| Display |
Type |
5.7-inch color active matrix TFT |
| Resolution |
640 x 480 pixels |
| Waveform Display |
Vertical |
10 div of 40 pixels |
| Horizontal |
12 div of 40 pixels |
| Power |
External |
Via Power Adapter BC430 |
| Input voltage |
10 V DC to 21 V DC |
| Power consumption |
5 W typical |
| Input connector |
5 mm jack |
| Internal |
Via Battery Pack BP290 |
| Battery power |
Rechargeable Li-Ion 10.8 V |
| Operating time |
7 hours with 50% backlight brightness |
| Charging time |
4 hours with test tool off, 7 hours with test tool on |
| Allowable ambient temp |
0 to 40 °C (32 to 104 °F) during charging |
| Memory |
Internal memory can store
20 data sets (screen
waveform and setup) |
Micro SD card slot with optional SD card (max size of 32 GB) |
| Mechanical |
Size |
259 x 132 x 55 mm
(10.2 x 5.2 x 2.15 in) |
| Weight |
1.4 kg (3.2 lb) including battery pack |
| Interface |
Optically isolated |
Transfer screen copies (bitmaps), settings and data |
| USB to PC/laptop |
OC4USB optically isolated USB adapter/cable, (optional), using
FlukeView® software for Windows®. |
| Optional WiFi adapter |
Fast transfer of screen copies (bitmaps), settings and data to
PC/laptop, tablet, smartphone, etc. A USB port is provided for
attaching the WiFi dongle. Do not use the USB port with a cable
for safety reasons. |
| Environmental |
| Environmental |
MIL-PRF-28800F, Class 2 |
| Temperature |
Battery Operation |
0 to 40 °C (32 to 104 °F) |
| Power Adapter Operation |
0 to 50 °C (32 to 122 °F) |
| Storage |
-20 to 60 °C (-4 to 140 °F) |
| Humidity (Operating) |
@ 0 to 10 °C (32 to 50 °F) |
Non-condensing |
| @ 10 to 30 °C (50 to 86 °F) |
95% |
| @ 30 to 40 °C (86 to 104 °F) |
75% |
| @ 40 to 50 °C (104 to 122 °F) |
45% |
| Storage |
@ -20 to 60 °C (-4 to 140 °F) |
Non-condensing |
| Altitude |
Operating at 3 km (10,000 feet) |
CAT III 600 V |
| Operating at 2 km (6,600 feet) |
CAT IV 600 V |
| Storage |
12 km (40,000 feet) |
EMC electromagnetic
compatibility |
International |
IEC 61326-1: Industrial, CISPR 11: Group 1,
Class A |
| Korea (KCC) |
Class A Equipment (Industrial Broadcasting &
Communication Equipment) |
| USA (FCC) |
47 CFR 15 subpart B. This product is
considered an exempt device per clause
15.103. |
Wireless radio with
adapter |
Frequency range |
2412 MHz to 2462 MHz |
| Output power |
<100 mW |
| Enclosure protection |
IP51, ref: EN/IEC60529 |
| Safety |
General |
IEC 61010-1: Pollution Degree 2 |
| Measurement |
IEC 61010-2-033: CAT IV 600 V/CAT III 750 V |
Max. input voltage input
A and B |
Direct on input or with leads |
600 Vrms CAT IV for derating |
With Banana-to-BNC Adapter
BB120 |
600 Vrms for derating |
Max. floating voltage from
any terminal to ground |
600 Vrms Cat IV, 750 Vrms up to 400 Hz |