
Drive Measurement Details  
Motor Type  3 phase asynchronous (induction)  
Power Source  Variable Frequency Drive  
Motor Frequency Range  40Hz to 70Hz  
Over/Under Voltage from Nominal V/f Curve (%)  15% to +15%  
Carrier Frequency Range  2.5kHz–20kHz  
Variable speed drive technology that is covered by the 438II  
Inverter Type  VSI only (voltage controlled) *  
Control Method  V/f control, openloop vector, closed loop vector, drives with encoders.  
Frequency  40 to 70 Hz  
* VSI drives are the most common drives. The alternative CSI drives are used in higher power applications.  
Variable speed drive technology NOT covered by the 438II  
Inverter Type  CSI (current source inverter)  
Motors type  Nonsynchronous (DC, stepper, permanent magnet etc.)  
Motor Frequency  <40 and >70 Hz  
Mechanical specifications  
Mechanical measurements can be performed on direct online motors with a 3 wire connection.  
Range  Resolution  Accuracy  Default limit  
Motor measurement  
Mechanical motor
Power 
0.7 kW to 746 kW
1 hp to 1000 hp 
0.1 kW
0.1 hp 
±3%^{1}
±3%^{1} 
100% = rated power
100% = rated power 

Torque  0 Nm to 10 000 Nm
0 lb ft to 10 000 lb ft 
0.1 Nm
0.1 lb ft 
±5%^{1}
±5%^{1} 
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* Factor (NEMA) 
0 to 0.20  –  ±1.5%  0.15  
Unbalance Derating* Factor 
0.7 to 1.0  –  indicative  NA  
Harmonics Derating* Factor 
0.7 to 1.0  –  indicative  NA  
Total NEMA Derating* Factor 
0.5 to 1.0  –  indicative  NA  
* Derating factors do not apply to motors powered by variable frequency drives.  
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. 

^{1}Add 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 (23 hours if the motor is 50 HP or higher) to obtain stable temperature 

Electrical specifications  
Model  Measurement range  Resolution  Accuracy  
Volt  
Vrms (ac+dc)  435II  1 V to 1000 V phase to neutral  0.01 V  ±0.1% of nominal voltage****  
Vpk  –  1 Vpk to 1400 Vpk  1 V  5% of nominal voltage  
Voltage Crest Factor (CF)  –  1.0 > 2.8  0.01  ±5%  
Vrms½  435II  0.1 V  ±0.2% of nominal voltage  
Vfund  435II  0.1 V  ±0.1% of nominal voltage  
Amps (accuracy excluding clamp accuracy)  
Amps (ac +dc)  i430Flex 1x  5 A to 6000 A  1 A  ±0.5% ±5 counts  
i430Flex 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  i430Flex  8400 Apk  1 Arms  ±5%  
1mV/A  5500 Apk  1 Arms  ±5%  
A Crest Factor (CF)  –  1 to 10  0.01  ±5%  
Amps½  i430Flex 1x  5 A to 6000 A  1 A  ±1% ±10 counts  
i430Flex 10x  0.5 A to 600 A  0.1 A  ±1% ±10 counts  
1mV/A 1x  5 A to 2000 A  1A  ±1% ±10 counts  
1mV/A 10x  0.5 A A to 200 A (ac only)  0.1 A  ±1% ±10 counts  
Afund  i430Flex 1x  5 A to 6000 A  1 A  ±0.5% ±5 counts  
i430Flex 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  
Hertz  
Hz  Fluke 435 @ 50 Hz nominal  42.500 Hz to 57.500 Hz  0.001 Hz  ±0.01 Hz  
Fluke 435 @ 60 Hz nominal  51.000 Hz to 69.000 Hz  0.001 Hz  ±0.01 Hz  
Power  
Watts (VA, var)  i430Flex  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)  i430Flex 10x  Depends on clamp scaling and V nominal  ±1% ±10 counts  
Energy loss  i430Flex 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 6100047  
Interharmonic order (n)  –  OFF, 1 to 50 Grouping: Harmonic and Interharmonic subgroups according to IEC 6100047  
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% *  
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(1min) 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 MILPRF28800F Class 2  
Display  Brightness: 200 cd/m 2 typ. using power adapter, 90 cd/m 2 typical using battery power Size: 127 mm x 88 mm (153 mm/6.0 in diagonal) LCD Resolution: 320 x 240 pixels Contrast and brightness: useradjustable, temperature compensated  
Memory  8GB SD card (SDHC compliant, FAT32 formatted) standard, upto 32GB optionally Screen save and multiple data memories for storing data including recordings (dependent on memory size)  
Realtime 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 noncondensing +30 °C ~ +40 °C: 75% RH noncondensing +40 °C ~ +50 °C: 45% RH noncondensing 

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) 

ElectroMagneticCompatibility (EMC)  EN 61326 (200512) for emission and immunity  
Interfaces  miniUSBB, 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  
* ±5% if ≥ 1 % of nominal voltage ±0.05% of nominal voltage if < 1% of nominal voltage 
Fluke 438II Power Quality and Motor Analyzer

Drive Measurement Details  
Motor Type  3 phase asynchronous (induction)  
Power Source  Variable Frequency Drive  
Motor Frequency Range  40Hz to 70Hz  
Over/Under Voltage from Nominal V/f Curve (%)  15% to +15%  
Carrier Frequency Range  2.5kHz–20kHz  
Variable speed drive technology that is covered by the 438II  
Inverter Type  VSI only (voltage controlled) *  
Control Method  V/f control, openloop vector, closed loop vector, drives with encoders.  
Frequency  40 to 70 Hz  
* VSI drives are the most common drives. The alternative CSI drives are used in higher power applications.  
Variable speed drive technology NOT covered by the 438II  
Inverter Type  CSI (current source inverter)  
Motors type  Nonsynchronous (DC, stepper, permanent magnet etc.)  
Motor Frequency  <40 and >70 Hz  
Mechanical specifications  
Mechanical measurements can be performed on direct online motors with a 3 wire connection.  
Range  Resolution  Accuracy  Default limit  
Motor measurement  
Mechanical motor
Power 
0.7 kW to 746 kW
1 hp to 1000 hp 
0.1 kW
0.1 hp 
±3%^{1}
±3%^{1} 
100% = rated power
100% = rated power 

Torque  0 Nm to 10 000 Nm
0 lb ft to 10 000 lb ft 
0.1 Nm
0.1 lb ft 
±5%^{1}
±5%^{1} 
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* Factor (NEMA) 
0 to 0.20  –  ±1.5%  0.15  
Unbalance Derating* Factor 
0.7 to 1.0  –  indicative  NA  
Harmonics Derating* Factor 
0.7 to 1.0  –  indicative  NA  
Total NEMA Derating* Factor 
0.5 to 1.0  –  indicative  NA  
* Derating factors do not apply to motors powered by variable frequency drives.  
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. 

^{1}Add 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 (23 hours if the motor is 50 HP or higher) to obtain stable temperature 

Electrical specifications  
Model  Measurement range  Resolution  Accuracy  
Volt  
Vrms (ac+dc)  435II  1 V to 1000 V phase to neutral  0.01 V  ±0.1% of nominal voltage****  
Vpk  –  1 Vpk to 1400 Vpk  1 V  5% of nominal voltage  
Voltage Crest Factor (CF)  –  1.0 > 2.8  0.01  ±5%  
Vrms½  435II  0.1 V  ±0.2% of nominal voltage  
Vfund  435II  0.1 V  ±0.1% of nominal voltage  
Amps (accuracy excluding clamp accuracy)  
Amps (ac +dc)  i430Flex 1x  5 A to 6000 A  1 A  ±0.5% ±5 counts  
i430Flex 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  i430Flex  8400 Apk  1 Arms  ±5%  
1mV/A  5500 Apk  1 Arms  ±5%  
A Crest Factor (CF)  –  1 to 10  0.01  ±5%  
Amps½  i430Flex 1x  5 A to 6000 A  1 A  ±1% ±10 counts  
i430Flex 10x  0.5 A to 600 A  0.1 A  ±1% ±10 counts  
1mV/A 1x  5 A to 2000 A  1A  ±1% ±10 counts  
1mV/A 10x  0.5 A A to 200 A (ac only)  0.1 A  ±1% ±10 counts  
Afund  i430Flex 1x  5 A to 6000 A  1 A  ±0.5% ±5 counts  
i430Flex 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  
Hertz  
Hz  Fluke 435 @ 50 Hz nominal  42.500 Hz to 57.500 Hz  0.001 Hz  ±0.01 Hz  
Fluke 435 @ 60 Hz nominal  51.000 Hz to 69.000 Hz  0.001 Hz  ±0.01 Hz  
Power  
Watts (VA, var)  i430Flex  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)  i430Flex 10x  Depends on clamp scaling and V nominal  ±1% ±10 counts  
Energy loss  i430Flex 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 6100047  
Interharmonic order (n)  –  OFF, 1 to 50 Grouping: Harmonic and Interharmonic subgroups according to IEC 6100047  
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% *  
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(1min) 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 MILPRF28800F Class 2  
Display  Brightness: 200 cd/m 2 typ. using power adapter, 90 cd/m 2 typical using battery power Size: 127 mm x 88 mm (153 mm/6.0 in diagonal) LCD Resolution: 320 x 240 pixels Contrast and brightness: useradjustable, temperature compensated  
Memory  8GB SD card (SDHC compliant, FAT32 formatted) standard, upto 32GB optionally Screen save and multiple data memories for storing data including recordings (dependent on memory size)  
Realtime 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 noncondensing +30 °C ~ +40 °C: 75% RH noncondensing +40 °C ~ +50 °C: 45% RH noncondensing 

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) 

ElectroMagneticCompatibility (EMC)  EN 61326 (200512) for emission and immunity  
Interfaces  miniUSBB, 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  
* ±5% if ≥ 1 % of nominal voltage ±0.05% of nominal voltage if < 1% of nominal voltage 