Fluke 1738 Advanced Power Logger

The Fluke 1738 power logger is ideal for conducting energy studies and more advanced power quality analysis.







Available December, 2015

Comprehensive power quality and energy studies – get the data you need to make critical decisions in real-time

The Fluke 1738 Three-Phase Advanced Power Logger built with Fluke Connect® mobile app and desktop software compatibility gives you the data you need to make critical power quality and energy decisions in real-time. Like the Fluke 1736 Power Logger, the 1738 Advanced Power Logger automatically captures and logs over 500 power quality parameters while also allowing you to troubleshoot more advanced power quality issues. Perform advanced analysis with an enhanced Power Quality Health Summary (EN50160) function that provides you with fast insight into overall electrical system health. The Power Quality Health Summary is based on detailed power quality data including viewable event waveform captures so you have even more visibility into the data you need to optimize system reliability and savings.

An optimized user interface, flexible current probes, and an intelligent measurement verification function that allows you to reduce measurement errors by digitally verifying and correcting common connection errors makes setup easier than ever and reduces measurement uncertainty. Access and share data remotely with your team via the Fluke Connect® app, or access your logger through your facilities WiFi infrastructure so you can maintain safer working distances and make critical decisions in real-time, reducing the need for protective equipment, site visits and check-ins. You can also quickly and easily chart and graph measurements to help identify issues and create detailed reports with the included Fluke Energy Analyze Plus software package. Optionally, you can create IEEE519 Reports giving you more insight into harmonic levels, voltage and current distortion, and load current (license required).

The Fluke 1738 is the ideal test tool for conducting energy studies and more advanced power quality logging.


Key measurements: Automaticall­y capture and log voltage, current, power, harmonics and associated power quality values.

Fluke Connect® compatible*: View data locally on the instrument, via Fluke Connect mobile app and desktop software or through your facilities WiFi infrastructure.

Convenient instrument powering: Power instrument directly from the measured circuit.

Highest safety rating in the industry: 600 V CAT IV/1000 V CAT III rated for use at the service entrance and downstream.

Measure all three phases and neutral: With included 4 flexible current probes.

Comprehensive logging: More than 20 separate logging sessions can be stored on the instruments. In fact, all measured values are automatically logged so you never loose measurement trends. They can even be reviewed during logging sessions and before downloading for real-time analysis.

Capture dips, swells, and inrush currents: Includes event waveform snapshot and high resolution RMS profile, along with date, timestamp and severity to help pinpoint potential root causes of power quality issues.

Power Quality Health Summary: Summarizes the most important power quality health parameters to provide fast insight into overall electrical system health, indicating whether more detailed analysis and reporting should be done.

Bright, color touch screen: Perform convenient in-the-field analysis and data checks with full graphical display.

Optimized user interface: Capture the right data every time with quick, guided, graphical setup and reduce uncertainty about your connections with the intelligent verification function.

Complete “in-the-field” setup through the front panel or Fluke Connect App: No need to return to the workshop for download and setup or to take a computer to the electrical panel.

Fully integrated logging: Connect other Fluke Connect devices to the Fluke 1738 to simultaneously log up to two other measurement parameters, virtually any parameter available on a Fluke Connect wireless digital multimeter.*

Energy Analyze Plus application software: Download and analyze every detail of energy consumption and power quality state of health with our automated reporting.


ParameterRangeResolutionIntrinsic Accuracy at Reference Conditions (% of Reading +% of Full Scale)
Voltage1000 V0.1 V±(0.2% + 0.01%)
Current: Direct inputi17xx-flex 1500 12″150 A0.1 A±(1% + 0.02%)
1500 A1 A±(1% + 0.02%)
i17xx-flex 3000 24″300 A1 A±(1% + 0.03%)
3000 A10 A±(1% + 0.03%)
i17xx-flex 6000 36″600 A1 A±(1.5% + 0.03%)
6000 A10 A±(1.5% + 0.03%)
i40s-EL clamp4 A1 mA±(0.7% + 0.02%)
40 A10 mA±(0.7% + 0.02%)
Frequency42.5 Hz to 69 Hz0.01 Hz±(0.1%)
Auxillary input±10 V dc0.1 mV±(0.2% + 0.02%)
Voltage min/max1000 V0.1 V±(1% + 0.1%)
Current min/maxDefined by accessoryDefined by accessory±(5% + 0.2%)
THD on voltage1000%0.1%±0.5
THD on current1000%0.1%±0.5
Voltage harmonics 2nd to 50th1000 V0.1 V≥ 10 V: ±5% of reading
< 10 V: ±0.5V
Current harmonics 2nd to 50thDefined by accessoryDefined by accessory≥ 3% of current range: ±5% of reading
< 3% of current range: ±0.15% of range
Intrinsic Uncertainty ±(% of reading +% of range)¹
ParameterInfluence quantityiFlex1500-12iFlex3000-24iFlex6000-36i40S-EL
150 A / 1500 A300 A / 3000 A600 A / 6000 A4 A / 40 A
Active Power PPF ≥ 0.991.2% + 0.005%1.2% + 0.0075%1.7% + 0.0075%1.2% + 0.005%
Active Energy EaPF ≥ 0.991.2% + 0.005%1.2% + 0.0075%1.7% + 0.0075%1.2% + 0.005%
Apparent power S0 ≤ PF ≤ 11.2% + 0.005%1.2% + 0.0075%1.7% + 0.0075%1.2% + 0.005%
Apparent Energy Eap0 ≤ PF ≤ 11.2% + 0.005%1.2% + 0.0075%1.7% + 0.0075%1.2% + 0.005%
Reactive power Q0 ≤ PF ≤ 12.5% of measured apparent power
Reactive Energy Er0 ≤ PF ≤ 12.5% of measured apparent power
Power Factor PF±0.025
Displacement Power Factor±0.025
Additional uncertainty in% of range¹VP-N>250 V0.015%0.0225%0.0225%0.015%
¹Range = 1000 V x Irange
Reference conditions:

  • Environmental: 23 °C ±5 °C, instrument operating for at least 30 minutes, no external electrical/magnetic field, RH <65%
  • Input conditions: Cosϕ/PF=1, Sinusoidal signal f=50 Hz/60 Hz, power supply 120 V/230 V ±10%.
  • Current and power specifications: Input voltage 1 ph: 120 V/230 V or 3 ph wye/delta: 230 V/400 V Input current: I > 10% of Irange
  • Primary conductor of clamps or Rogowski coil in center position
  • Temperature coefficient: Add 0.1 x specified accuracy for each degree C above 28 °C or below 18 °C


Electrical Specifications
Power Supply
Voltage range100 V to 500 V using safety plug input when powering from the measurement circuit
100 V to 240 V using standard power cord (IEC 60320 C7)
Power consumptionMaximum 50 VA (max. 15 VA when powered using IEC 60320 input)
Efficiency≥ 68.2% (in accordance with energy efficiency regulations)
Maximum no-load consumption< 0.3 W only when powered using IEC 60320 input
Mains power frequency50/60 Hz ±15%
BatteryLi-ion 3.7 V, 9.25 Wh, customer-replaceable
On-battery runtimeFour hours in standard operating mode, up to 5.5 hours in power saving mode
Charging time< 6 hours
Data Acquisition
Resolution16-bit synchronous sampling
Sampling frequency10.24 kHz at 50/60 Hz, synchronized to mains frequency
Input signal frequency50/60 Hz (42.5 to 69 Hz)
Circuit types1-φ, 1-φ IT, Split phase, 3-φ delta, 3-φ wye, 3-φ wye IT, 3-φ wye balanced, 3-φ Aron/Blondel (2-element delta), 3-φ delta open leg, Currents only (load studies)
Data storageInternal flash memory (not user replaceable)
Memory sizeTypical 10 logging sessions of 8 weeks with 1-minute intervals and 500 events¹
¹The number of possible logging sessions and logging period depends on user requirements.
Basic Interval
Measured parametersVoltage, current, aux, frequency, THD V, THD A, power, power factor, fundamental power, DPF, energy
Averaging intervalUser selectable: 1 sec, 5 sec, 10 sec, 30 sec, 1 min, 5 min, 10 min, 15 min, 30 min
Averaging time min/max valuesVoltage, Current: Full cycle RMS updated every half cycle (URMS1/2 according to IEC61000-4-30 Aux, Power: 200ms
Demand Interval (Energy Meter Mode)
Measured parametersEnergy (Wh, varh, VAh), PF, maximum demand, cost of energy
IntervalUser selectable: 5 min, 10 min, 15 min, 20 min, 30 min, off
Power Quality Measurements
Measured parameterVoltage, frequency, unbalance, voltage harmonics, THD V, current, harmonics, THD A, TDD
Averaging interval10 min
Individual harmonics2nd to 50th harmonic
Total harmonic distortionCalculated on 50 harmonics
EventsVoltage: dips, swells, interruptions, current: inrush current
Triggered recordingsFull cycle RMS updated every half cycle of voltage and current (Urms1/2 according to IEC61000-4-30)
Waveform of voltage and current
Standards Compliance
HarmonicsIEC 61000-4-7: Class 1
IEEE 519 (short time harmonics)
Power qualityIEC 61000-4-30 Class S, IEC62586-1 (PQI-S device)
PowerIEEE 1459
Power quality complianceEN50160 (for measured parameters)
USB-AFile transfer via USB flash drive, firmware updates
Max. current: 120 mA
WiFiFile transfer and remote control via direct connection or WiFi infrastructure
BluetoothRead auxiliary measurement data from Fluke Connect® 3000 series modules (requires 1738 or 1736 upgrade option)
USB-miniData download device to PC
Voltage Inputs
Number of inputs4 (3 phases and neutral)
Maximum input voltage1000 Vrms, CF 1.7
Input impedance10 MΩ
Bandwidth (-3 dB)42.5 Hz – 3.5 kHz
Scaling1:1 and variable
Measurement category1000 V CAT III/600 V CAT IV
Current Inputs
Number of inputs4, mode selected automatically for attached sensor
Input voltageClamp input: 500 mVrms/50 mVrms; CF 2.8
Rogowski coil input150 mVrms/15 mVrms at 50 Hz, 180 mVrms/18 mVrms at 60 Hz; CF 4; all at nominal probe range
Range1 A to 150 A/10 A to 1500 A with thin flexible current probe i17XX-flex1500 12″
3 A to 300 A/30 A to 3000 A with thin flexible current probe i17XX-flex3000 24″
6 A to 600 A/60 A to 6000 A with thin flexible current probe i17XX-flex6000 36″
40 mA to 4 A/0.4 A to 40 A with 40 A clamp i40s-EL
Bandwidth (-3 dB)42.5 Hz – 3.5 kHz
Scaling1:1 and variable
Auxiliary Inputs
Number of inputs2
Input range0 to ±10 V dc, 1reading/s
Scale factor (available 2014)Format: mx + b (gain and offset) user configurable
Displayed units (available 2014)User configurable (7 characters, for example, °C, psi, or m/s)
Wireless Connection
Number of inputs2
Supported modulesFluke Connect® 3000 series
Acquisition1 reading/s
Environmental Specifications
Operating temperature-10 °C to +50 °C (14 °F to 122 °F)
Storage temperature-20 °C to +60 °C (-4 °F to 140 °F), with battery: -20 °C to +50 °C (-4 °F to 122 °F)
Operating humidity10 °C to 30 °C (50 °F to 86 °F) max. 95% RH
30 °C to 40 °C (86 °F to 104 °F) max. 75% RH
40 °C to 50 °C (104 °F to 122 °F) max. 45% RH
Operating altitude2000 m (up to 4000 m derate to 1000 V CAT II/600 V CAT III/300 V CAT IV)
Storage altitude12,000m
EnclosureIP50 in accordance with EN60529
VibrationMIL-T-28800E, Type 3, Class III, Style B
SafetyIEC 61010-1
IEC Mains Input: Overvoltage Category II, Pollution Degree 2
Voltage Terminals: Overvoltage Category IV, Pollution Degree 2
IEC 61010-2-031: CAT IV 600 V / CAT III 1000 V
Electromagnetic compatibilityEN 61326-1: Industrial CISPR 11: Group 1, Class A
Korea (KCC): Class A Equipment (industrial broadcasting and communication equipment)
USA (FCC): 47 CFR 15 subpart B. This product is considered an exempt device per clause 15.103
Temperature coefficient0.1 x accuracy specification/°C
General Specifications
Color LCD display4.3-inch active matrix TFT, 480 pixels x 272 pixels, resistive touch panel
WarrantyInstrument and power supply: Two-years (battery not included)
Accessories: one-year
Calibration cycle: two-years
DimensionsInstrument: 19.8 cm x 16.7 cm x 5.5 cm (7.8 in x 6.6 in x 2.2 in)
Power supply: 13.0 cm x 13.0 cm x 4.5 cm (5.1 in x 5.1 in x 1.8 in)
Instrument with power supply attached: 19.8 cm x 16.7 cm x 9 cm (7.8 in x 6.6 in x 3.5 in)
WeightInstrument: 1.1 kg (2.5 lb)
Power supply: 400 g (0.9 lb)
Tamper protectionKensington lock slot
i17xx-flex 1500 12″ Flexible Current Probe Specifications
Measuring range1 to 150 A ac/10 to 1500 A ac
Nondestructive current100 kA (50/60 Hz)
Intrinsic error at reference condition*±0.7% of reading
Accuracy 173x + iFlex±(1% of reading + 0.02% of range)
Temperature coefficient over operating temperature range0.05% of reading/°C 0.09% of reading/°F
Working voltage1000 V CAT III, 600 V CAT IV
Probe cable length305 mm (12 in)
Probe cable diameter7.5 mm (0.3 in)
Minimum bending radius38 mm (1.5 in)
Output cable length2 m (6.6 ft)
Weight115 g
Probe cable materialTPR
Coupling materialPOM + ABS/PC
Output cableTPR/PVC
Operating temperature-20 °C to +70 °C (-4 °F to 158 °F) temperature of conductor under test shall not exceed 80 °C (176 °F)
Temperature, non-operating-40 °C to +80 °C (-40 °F to 176 °F)
Relative humidity, operating15% to 85% non-condensing
IP ratingIEC 60529:IP50
* Reference condition:

  • Environmental: 23 °C ±5 °C, no external electrical/magnetic field, RH 65%
  • Primary conductor in center position



Models (4)
Model NameDescription
Fluke 1738/BFluke 1738/B Advanced Power Logger
Fluke 1738/EUSFluke 1738/EUS Advanced Power Logger
Fluke 1738/INTLFluke 1738/INTL Advanced Power Logger
Fluke 1738/WINTLFluke 1738/WINTL Advanced Power Logger



Cables & Hardware (2)
Model NameDescription
FLUKE-173X AUXFluke 173X AUX
173X-Hanger KitFluke 173X Hanger Strap
Cases & Holsters (1)
Model NameDescription
C173XFluke C17XX Soft Case
Current Clamps (11)
Model NameDescription
FLUKE-17XX i40s-ELFluke 17XX i40s-EL Clamp-on Current Transformers
FLUKE-17XX i40s-EL/3pkFluke 17XX i40s-EL Clamp-on Current Transformers 3 pack
i17XX-flex1500Fluke i17XX-flex1500 iFlex® Current Clamp
i17XX-flex1500/3pkFluke i17XX-flex1500/3pk iFlex® Current Clamps
i17XX-flex1500/4pkFluke i17XX-flex1500/4pk iFlex® Current Clamps
i17XX-flex3000Fluke i17XX-flex3000 iFlex® Current Clamp
i17XX-flex3000/3pkFluke i17XX-flex3000/3pk iFlex® Current Clamp
i17XX-flex3000/4pkFluke i17XX-flex3000/4pk iFlex® Current Clamp
i17XX-flex6000Fluke i17XX-flex6000 iFlex® Current Clamp
i17XX-flex6000/3pkFluke i17XX-flex6000/3pk iFlex® Current Clamp
i17XX-flex6000/4pkFluke i17XX-flex6000/4pk iFlex® Current Clamp
Software (1)
Model NameDescription
Fluke 1736/UPGRADEFluke 1736/UPGRADE for Fluke 1736 Power Loggers
Test Leads, Probes & Clips (4)
Model NameDescription
FLUKE-17xx-TL 0.1MFluke 17XX-TL 1.0M Test Lead Set
FLUKE-17XX-TL 1.5MFluke 17XX-TL 1.5M Test Lead Set
MP1-MAGNET PROBE 1Fluke MP1 Magnet Probe 1, Magnetic Probe Tips
Fluke WC100Fluke WC100 Color Localization Set



1736/1738 Users ManualDownload
1736/1738 Users Manual SupplementDownload
USB1 FC Users ManualDownload
1732, 1734, 1736, 1738 Statement of Memory VolatilityDownload
1732/1734/1736/1738 3540FC Calibration ManualDownload
1736/1738 Safety SheetDownload
Auxiliary Input Adapter for the 17xx Instruction SheetDownload
Auxiliary Input Adapter for the 17xx Instruction Sheet SupplementDownload
Energy Analyze Plus Online HelpDownload
MP1 Magnet Probe Instruction SheetDownload
Application Notes (4)
4 Steps to take after power quality data has been collectedDownload
6 Things you need to do before making power quality measurementsDownload
A guide to 30 day load studies with Fluke Power and Energy LoggersDownload
Harmonics Standards: What are they and how can you use them?Download
Data Sheets (1)
Fluke 1736 and 1738 Three-Phase Power Loggers Data SheetDownload