Fieldpiece has built a strong reputation in the HVAC and electrical industry for producing rugged, technician-focused tools. Two of their popular clamp meters, the SC620 and the SC640, are often compared by professionals looking for reliability and accuracy.
While both models are part of Fieldpiece’s Advanced Series, they are intended for slightly different applications.
This article will break down their features, differences, and help you decide which one is the best fit for your work.
📋 Overview of the Fieldpiece SC620
The SC620 is designed as a versatile HVAC clamp meter with a solid feature set, making it ideal for technicians who need accurate measurements without the bulk of extra advanced diagnostics.
Key Features:
- True RMS accuracy for precise readings
- Measures AC/DC voltage and current
- Jaw opening: 1 inch
- Microamp measurement for flame sensors
- Dual display with backlight
- Temperature measurement with included thermocouple
- Compact and rugged design
The SC620 provides all the essentials for HVAC troubleshooting in a smaller form factor.
📋 Overview of the Fieldpiece SC640
The SC640 builds on the SC620’s functionality with added features and a slightly larger design. It’s aimed at technicians who want more capability, especially for demanding HVAC and electrical work.
Key Features:
- True RMS accuracy
- Measures AC/DC voltage and current (higher ranges than SC620)
- Jaw opening: 1.25 inch (larger conductors)
- Microamp measurement for flame sensors
- Inrush current measurement
- Dual display with backlight
- Temperature measurement with included thermocouple
The SC640 includes inrush current measurement and a wider jaw, making it more suitable for professionals working with larger systems.
🔍 Side-by-Side Comparison
| Feature / Spec | Fieldpiece SC620 | Fieldpiece SC640 |
|---|---|---|
| Series | Advanced Series | Advanced Series |
| True RMS | Yes | Yes |
| AC Current Range | Up to 400A | Up to 600A |
| Jaw Opening | 1 inch | 1.25 inch |
| Voltage Measurement | AC/DC | AC/DC |
| Microamps (Flame Sensor Test) | Yes | Yes |
| Inrush Current Measurement | No | Yes |
| Temperature Measurement | Yes | Yes |
| Display | Dual display with backlight | Dual display with backlight |
| Size/Weight | More compact | Slightly larger |
| Best For | HVAC techs needing core features | HVAC/electrical techs needing higher ranges and inrush testing |
✅ Pros and Cons
Fieldpiece SC620
Pros:
- Compact and lightweight design
- Covers all essential HVAC measurements
- More affordable than SC640
Cons:
- No inrush current measurement
- Smaller jaw opening (1 inch)
- Lower current range (400A max)
Fieldpiece SC640
Pros:
- Higher current range (up to 600A)
- Inrush current measurement included
- Larger jaw for bigger conductors
- Rugged and accurate
Cons:
- Slightly bulkier
- Higher cost compared to SC620
🏆 Verdict: SC620 vs SC640
- Choose the Fieldpiece SC620 if you want a compact, affordable clamp meter with all the essential HVAC features. It’s great for everyday use without unnecessary extras.
- Choose the Fieldpiece SC640 if you need higher measurement capacity, inrush current testing, and larger jaw size, ideal for more advanced HVAC and electrical work.
Both models are durable, accurate, and built with technicians in mind. Your choice depends on whether you need a streamlined tool (SC620) or one with expanded diagnostic power (SC640).