Quickly and easily discover electrical and mechanical performance of electric motors, and evaluate power quality with a single test tool
The Fluke 438-II Power Quality and Motor Analyzer adds key mechanical measurement capabilities for electric motors to the advanced power quality analysis functions of the Fluke 435 Series II Power Quality Analyzers. Quickly and easily measure and analyze key electrical and mechanical performance parameters such as power, harmonics, unbalance, motor speed, torque and mechanical power without the need of mechanical sensors. Fluke 434-II, 435-II and 437-II Power Quality Analyzer users can add motor analysis capabilities to their existing units with the Fluke-438-II/MA Motor Analyzer upgrade kit.
The ideal portable motor analysis test tool, the 438-II can help locate, predict, prevent, and troubleshoot power quality problems in three-phase and single-phase power distribution systems, while giving technicians the mechanical and electrical information they need to effectively evaluate motor performance.
- Measure key parameters on direct-on-line motors including torque, RPM, mechanical power and motor efficiency
- Perform dynamic motor analysis by plotting of motor derating factor against load according to NEMA/IEC guidelines
- Calculate mechanical power and efficiency without the need of mechanical sensors, just connect to the input conductors and you're ready to go
- Measure electrical power parameters such as voltage, current, power, apparent power, power factor, harmonic distortion and unbalance to identify characteristics that impact motor efficiency
- Identify power quality issues such as dips, swells, transients, harmonics and unbalance
- PowerWave data technology captures fast RMS data, and shows half-cycle averages and waveforms to characterize electrical system dynamics (generator start-ups, UPS switching etc.)
- Waveform capture function captures 100/120 cycles (50/60 Hz) of each event detected event, in all modes, without set-up
- Automatic transient mode captures waveform data at 200 kS/s on all phases simultaneously up to 6 kV
- Fluke Connect® compatible* – view data locally on the instrument, via Fluke Connect mobile app and PowerLog 430-II desktop software
- Safety rated for industrial applications 600 V CAT IV/1000 V CAT III rated for use at the service entrance and downstream
Fluke 438-II mechanical metering functions
Calculates the amount of rotational force (displayed in lb.ft or Nm) developed by a motor and transmitted to a driven mechanical load. The motor torque is the single most critical variable that characterizes the instantaneous mechanical performance of rotating equipment driven by electric motors.
Provides the instantaneous motor shaft rotational speed. Combined with the motor torque, motor speed provides a snapshot of the mechanical performance of rotating equipment driven by electric motors.
Motor mechanical load
Measures the actual mechanical power (displayed in hp or kW) produced by motors and provides a direct link to overloading conditions without simply basing it on the motor current.
Shows the effectiveness of each motor within a machine, assembly line, plant, and/or facility in converting electric power to useful mechanical work. By properly aggregating the efficiencies of a population of motors the total (aggregate) efficiency can be estimated. Comparisons to expected motor efficiencies at observed operating conditions can help quantify the cost associated with motor energy inefficiency.
How it works
Using proprietary algorithms, the Fluke 438-II Power Quality and Motor Analyzer uses three-phase current and voltage waveforms to calculate motor torque, speed, load and efficiency at a 1 second update rate. The motor air gap field, as observed via the voltage/current waveforms, provides the basis for the measurements. Mechanical sensors and intrusive no-load motor testing are not required, making it faster than ever to analyze overall electric motor performance.
Electrical motor analysis
The Fluke 438-II provides a complete breakdown of electrical parameters. Prior to beginning motor analysis, it's recommended to make base line power quality measurements to assess the state of harmonics and unbalance on the electrical service output as these two properties can have a serious negative impact, on motor performance.
When in Motor Analysis mode, results are summarized for electrical performance, mechanical performance and derating (according to NEMA recommendations).
The easy to understand four-level color severity scale indicates motor performance in relation to the recommended electrical parameter levels including rated power, power factor, unbalance and harmonics.
For mechanical power you can instantly view the mechanical output power along with motor torque and speed. The mechanical output power is instantly compared with electrical power to provide you with live efficiency measurements. With this feature you can easily measure machine performance during each operation cycle.
The NEMA derating screen is updated as the load and the electrical conditions change, and each new measurement is plotted on the tolerance graph as a "+". In this example we can see that motor is within tolerance but is close to the service factor. This indicates that there may be a need for power quality mitigation, motor maintenance or some other performance improving adjustment. By frequently performing these tests over time, known benchmarks and performance trends can be created, enabling informed maintenance investment decisions.
Motor measurement Range Resolution Accuracy Default limit Mechanical motor
0.7 kW to 746 kW
1 hp to 1000 hp
100% = rated power
100% = rated power
Torque 0 Nm to 10 000 Nm
0 lb ft to 10 000 lb ft
0.1 lb ft
100% = rated torque
100% = rated torque
rpm 0 rpm to 3600 rpm 1 rpm ±3%1 100% = rated rpm Efficiency 0% to 100% 0.10% ±3%1 NA Unbalance (NEMA) 0% to 100% 0.10% ±0.15% 5% Harmonics Voltage
0 to 0.20 0.1 ±1.5% 0.15 Unbalance Derating
0.7 to 1.0 0.1 indicative NA Harmonics Derating
0.7 to 1.0 0.1 indicative NA Total NEMA Derating
0.5 to 1.0 0.1 indicative NA Notes: Supports motor design types NEMA A, B, C, D & E and IEC type H and N.
Rated torque is calculated from rated power and rated speed.
Update rate of Motor Measurements is 1x per second.
Default Trend duration is 1 week.
1Add 5% error when selecting Motor design type Other
Specification valid for Motor Power > 30% of rated power
Specification valid at stable operating temperature. Run the motor for at least 1 hour at full load
(2-3 hours if the motor is 50 HP or higher) to obtain stable temperature
Product Specifications Volt Model Measurement Range Resolution Accuracy Vrms (AC + DC) 1 V to 1000 V phase to neutral 0.01 V ±0.1% of nominal voltage1 Vpk 1 Vpk to 1400 Vpk 1 V 5% of nominal voltage Voltage Crest Factor (CF) 1.0 > 2.8 0.01 ±5% Vrms½ 0.1 V ±0.2% of nominal voltage Vfund 0.1 V ±0.1% of nominal voltage Amps (accuracy excluding clamp accuracy) Amps (AC + DC) i430-Flex 1x 5 A to 6000 A 1 A ±0.5% ±5 counts i430-Flex 10x 0.5 A to 600 A 0.1 A ±0.5% ±5 counts 1mV/A 1x 5 A to 2000 A 1A ±0.5% ±5 counts 1mV/A 10x 0.5 A A to 200 A (AC only) 0.1 A ±0.5% ±5 counts Apk i430-Flex 8400 Apk 1 Arms ±5% 1mV/A 5500 Apk 1 Arms ±5% A Crest Factor (CF) 1 to 10 0.01 ±5% Amps½ i430-Flex 1x 5 A to 6000 A 1 A ±1% ±10 counts i430-Flex 10x 0.5 A to 600 A 0.1 A ±1% ±10 counts 1mV/A 1x 5 A to 2000 A 1 A ±1% ±10 counts 1mV/A 10x 0.5 A A to 200 A (AC only) 0.1 A ±1% ±10 counts Afund i430-Flex 1x 5 A to 6000 A 1 A ±0.5% ±5 counts i430-Flex 10x 0.5 A to 600 A 0.1 A ±0.5% ±5 counts 1mV/A 1x 5 A to 2000 A 1 A ±0.5% ±5 counts 1mV/A 10x 0.5 A A to 200 A (AC only) 0.1 A ±0.5% ±5 counts Hz Fluke 434 @ 50 Hz Nominal 42.50 Hz to 57.50 Hz 0.01 Hz ±0.01 Hz Fluke 434 @ 60 Hz Nominal 51.00 Hz to 69.00 Hz 0.01 Hz ±0.01 Hz Power Watts (VA, var) i430-Flex max 6000 MW 0.1 W to 1 MW ±1% ±10 counts 1 mV/A max 2000 MW 0.1 W to 1 MW ±1% ±10 counts Power Factor (Cos j/DPF) 0 to 1 0.001 ±0.1% @ nominal load conditions Energy kWh (kVAh, kvarh) i430-Flex 10x Depends on clamp scaling and V nominal ±1% ±10 counts Energy Loss i430-Flex 10x Depends on clamp scaling and V nominal ±1% ±10 counts Excluding line resistance accuracy Harmonics Harmonic Order (n) DC, 1 to 50 Grouping: Harmonic groups according to IEC 61000-4-7 Inter-Harmonic Order (n) OFF, 1 to 50 Grouping: Harmonic and Interharmonic subgroups according to IEC 61000-4-7 Volts % f 0.0% to 100% 0.1% ±0.1% ±n x 0.1% r 0.0% to 100% 0.1% ±0.1% ±n x 0.4% Absolute 0.0 to 1000 V 0.1 V ±5%1 THD 0.0% to 100% 0.1% ±2.5% Amps % f 0.0% to 100% 0.1% ±0.1% ±n x 0.1% r 0.0% to 100% 0.1% ±0.1% ±n x 0.4% Absolute 0.0 to 600 A 0.1 A ±5% ±5 counts THD 0.0% to 100% 0.1% ±2.5% Watts % f or r 0.0% to 100% 0.1% ±n x 2% Absolute Depends on clamp scaling and V nominal — ±5% ±n x 2% ±10 counts THD 0.0% to 100% 0.1% ±5% Phase Angle -360° to +0° 1° ±n x 1° Flicker Plt, Pst, Pst (1 min) Pinst 0.00 to 20.00 0.01 ±5% Unbalance Volts % 0.0% to 20.0% 0.1% ±0.1% Amps % 0.0% to 20.0% 0.1% ±1% Mains Signaling Threshold Levels Threshold, limits and signaling duration is programable for two signaling frequencies — — Signaling Frequency 60 Hz to 3000 Hz 0.1 Hz Relative V % 0% to 100% 0.10% ±0.4% Absolute V3s (3 second avg.) 0.0 V to 1000 V 0.1 V ±5% of nominal voltage General Specifications Case Design Rugged, shock proof with integrated protective holster Drip and dust proof IP51 according to IEC60529 when used in tilt stand position Shock and vibration Shock 30 g, vibration: 3 g sinusoid, random 0.03 g 2 /Hz according to MIL-PRF-28800F Class 2 Display Brightness: 200 cd/m 2 typ. using power adapter, 90 cd/m 2 typical using battery power Size: 127 x 88 mm (153 mm/6.0 in diagonal) LCD Resolution: 320 x 240 pixels Contrast and brightness: user-adjustable, temperature compensated Memory 8GB SD card (SDHC compliant, FAT32 formatted) standard, upto 32 GB optionally Screen save and multiple data memories for storing data including recordings (dependent on memory size) Real-Time Clock Time and date stamp for Trend mode, Transient display, System Monitor and event capture Environmental Operating Temperature 0°C ~ +40°C; +40°C ~ +50°C excl. battery Storage Temperature -20°C ~ +60°C Humidity +10°C ~ +30°C: 95% RH non-condensing
+30°C ~ +40°C: 75% RH non-condensing
+40°C ~ +50°C: 45% RH non-condensing
Maximum Operating Altitude Up to 2,000 m (6666 ft) for CAT IV 600 V, CAT III 1000 V
Up to 3,000 m (10,000 ft) for CAT III 600 V, CAT II 1000 V
Maximum storage altitude 12 km (40,000 ft)
Electro-Magnetic-Compatibility (EMC) EN 61326 (2005-12) for emission and immunity Interfaces Mini-USB-B, Isolated USB port for PC connectivity SD card slot accessible behind instrument battery Warranty Three years (parts and labor) on main instrument, one year on accessories View full family specifications » 1. ±5% if ≥ 1% of nominal voltage ±0.05% of nominal voltage if < 1% of nominal voltage
2. 50Hz/60Hz nominal frequency according to IEC 61000-4-30
3. 400Hz measurements are not supported for Flicker, Mains Signaling and Monitor Mode
4. For nominal voltage 50 V to 500 V
Batteries, Chargers & Adapters
Cases & Holsters
Model Name Description Fluke C435 Fluke C435 Hard Rolling Case
Model Name Description Fluke i30s Fluke i30s AC/DC Current Clamp Fluke Store Fluke-i310s Fluke i310s Current Probe Fluke Store Fluke i400s Fluke i400s AC Current Clamp Fluke Store Fluke i430 Fluke i430 Flex 4 Pack Fluke Store Fluke i5S Fluke i5S AC Current Clamp Fluke Store Fluke i5sPQ3 Fluke i5sPQ3, 5 A AC Current Clamps, 3-pack Fluke Store Fluke-i6000s Flex Fluke i6000sFlex AC Current Probe
Model Name Description Fluke HH290 Fluke HH290 Hanging Hook for ScopeMeter 190-Series II
Test Leads, Probes & Clips
Model Name Description FLK-FC-SD CARD Fluke Connect Wireless SD Card
Title 438-II Users Manual Download 438-II Users Manual Download 438-II Users Manual Download 438-II Users Manual Download 438-II Users Manual Download 438-II Users Manual Download 438-II Users Manual Download 438-II Users Manual Download 438-II Users Manual Download 438-II Users Manual Download 438-II Users Manual Download 438-II Users Manual Download
Title Fluke 438-II Power Quality and Motor Analyzer Data Sheet Download