Fluke 378 FC vs 393 FC: Which Clamp Meter Is Right for Your High-Voltage Jobs?

Not all clamp meters are created equal—especially when you’re dealing with sensitive equipment like solar panels, data center boards, or high-voltage systems. In such high-stakes situations, there’s no room for guesswork. You need a tool that works the way you do.

Among the wide range of clamp meters on the market, Fluke has introduced two standout models: the Fluke 378 FC and the Fluke 393 FC. But which one is the right choice for you?

In this article, we’ve compared these two models based on technical specifications and real feedback from solar technicians and industrial maintenance professionals. This guide will help you choose the right tool to ensure precise, reliable measurements every time.

Fluke 378 fc vs 393 fc specs

Before choosing the right measuring tool, taking a close look at the technical specifications can simplify your decision-making process. In the table below, we compare the Fluke 378 FC and Fluke 393 FC based on key features such as current, voltage, safety rating, dust and water resistance, measurement flexibility, and connectivity options.^{1 2}

On a solar farm in Abu Dhabi, the 393 FC saved us hours thanks to its DC polarity check. No false readings, no retesting. But for indoor switchboards and general service calls, I carry the 378 FC—it’s just faster and fits better. Certified Solar Engineer, MME Customer, 2024

Fluke 378 FC – Flexible, Fast, and Great for Troubleshooting

• Used by building maintenance teams for HVAC checks where the flexible iFlex clamp helps reach around thick cable bundles.
• Ideal for facilities with legacy electrical panels where space is limited and speed matters.

One field engineer in Dubai reported saving 20 minutes per inspection just because the iFlex reached spots traditional jaws couldn’t.

Fluke 393 FC – Engineered for Solar and High-Voltage DC

• Frequently used in solar installations from Abu Dhabi to California where DC voltage can exceed 1000V.
• In a solar inverter commissioning project, the 393 FC’s visual polarity detection helped reduce wiring errors and rework time by 30%.
• Trusted by field inspectors working with rooftop solar arrays and EV charging stations exposed to dust and unpredictable weather.

Fluke 378 FC – Flexible, Fast, and Great for Troubleshooting

• Perfect for electricians who need to measure AC/DC voltage and current quickly with the iFlex flexible current probe.
• Designed for tight spots like control panels or crowded electrical cabinets.
• Ideal for general electrical work, equipment diagnostics, and field troubleshooting.

Fluke 393 FC – Engineered for Solar and High-Voltage DC

• Specifically built for solar photovoltaic (PV) systems, 1500 V DC-rated equipment, and environments where IP54 protection matters.
• Features like DC polarity indication and visual continuity LED help solar pros avoid installation mistakes.
• CAT III 1500 V DC rating makes it unique and compliant with solar field safety protocols. ³

Which Fluke Clamp Meter Fits Your Workflow? A Real-World Buying Guide

When deciding between the Fluke 378 FC and the 393 FC, consider your environment and technical needs:

If you’re working primarily with solar photovoltaic (PV) systems, the Fluke 393 FC is your go-to choice. It’s designed with solar technicians in mind, offering DC polarity indication and a 1500 V DC rating—features crucial for safe and error-free installations.

If your work requires protection against dust or splashes, especially outdoors or in industrial environments, again, the 393 FC—with its IP54 rating—is the safer bet.

On the other hand, if you need flexibility when measuring high currents, especially in tight spaces like switchboards or behind server racks, the 378 FC stands out. It includes the iFlex flexible current probe, allowing measurements up to 2500 A and easier access where standard jaws don’t fit.

For applications demanding more than 1000A AC measurement, the 378 FC is clearly the better option.

Also, if you frequently need to perform quick electrical spot checks, the 378 FC’s lightweight build and iFlex efficiency make it ideal for fast-paced environments.

Ultimately, go with the 378 FC if you prioritize current flexibility and versatility. Choose the 393 FC if your work involves solar energy, outdoor conditions, or high-voltage DC systems.⁴

Can’t decide between models? Get a free consultation with our experts. Click here to open popup

1. Fluke Corporation. (2023). Fluke 378 FC True-RMS Clamp Meter with iFlex® Datasheet[↩]
2. Fluke Corporation. (2023). Fluke 393 FC CAT III 1500V True-RMS Clamp Meter Datasheet.[↩]
3. National Fire Protection Association (NFPA). (2023). NFPA 70®: National Electrical Code® (NEC) 2023 Edition.[↩]
4. Fluke Corporation. (2022). Choosing the Right Clamp Meter. Fluke Blog.[↩]