Fluke 377 vs 378 Clamp Meters – What’s the difference?

Fluke’s 377 and 378 are two popular clamp meters. Both models are designed to deliver the accuracy and reliability that Fluke is known for.

In this article, we’ll compare the Fluke 377 and Fluke 378 to help you decide which multimeter is best suited for your needs.

Whether you’re involved in complex diagnostics or routine checks, understanding the differences between these two is important before you make a purchase decision on either.

Fluke 377FC AC/DC TRMS Non-Contact Voltage Wireless Clamp w/iFlex

Here’s a detailed comparison table that highlights the main features and specifications of the Fluke 377 and Fluke 378 clamp meters. This will help you understand the differences and similarities between these two advanced models from Fluke, allowing you to choose the one that best suits your specific needs.

Comparison Table: Fluke 377 vs Fluke 378

Feature/SpecificationFluke 377Fluke 378
Measurement CapabilitiesAC/DC voltage, AC/DC current, resistance, continuity, frequency, capacitanceAC/DC voltage, AC/DC current, resistance, continuity, frequency, capacitance, power factor
Clamp Jaw Opening34 mm34 mm
Current Measurement2500 A AC/DC (via iFlex flexible current probe)2500 A AC/DC (via iFlex flexible current probe)
Voltage Measurement1000 V AC/DC1000 V AC/DC
True RMSYesYes
FieldSense TechnologyYes, for non-contact voltage measurementYes, for non-contact voltage measurement
Bluetooth ConnectivityYes, connects to Fluke Connect appYes, connects to Fluke Connect app
DisplayLarge, easy-to-read display with backlightLarge, easy-to-read display with backlight, plus power quality indicators
Safety RatingCAT III 1000 V, CAT IV 600 VCAT III 1000 V, CAT IV 600 V
Inrush CurrentYesYes
Power Factor MeasurementNoYes
Warranty3 years3 years
Additional FeaturesIntegrated VFD low pass filter, power quality indicators (PQI) for troubleshooting power systems
PriceSlightly lower than Fluke 378Slightly higher due to additional features

Key Differences Highlighted:

  • Power Factor Measurement: The Fluke 378 includes power factor measurement capabilities, which is useful for assessing the efficiency of electrical systems and is essential for certain professional applications.
  • Additional Features: The Fluke 378 offers advanced troubleshooting features like a low pass filter for variable frequency drives (VFDs) and power quality indicators. These features make it especially valuable for complex diagnostics in industrial and commercial settings.

Fluke 378FC AC/DC TRMS Non-Contact Voltage Wireless Clamp w/PQ Indicator & iFlex


Both the Fluke 377 and 378 are top-of-the-line clamp meters designed for professionals who need reliable, precise tools for electrical measurements. The choice between the two will largely depend on specific needs:

  • The Fluke 377 is an excellent, slightly more affordable option for those who need robust, general electrical testing capabilities without the need for specialized power quality measurements.
  • The Fluke 378 is better suited for professionals who require advanced features for detailed diagnostics, especially in environments involving VFDs or where power quality assessment is critical.

Fluke 377FC AC/DC TRMS Non-Contact Voltage Wireless Clamp w/iFlex