When it comes to HVAC and electrical work, accuracy and reliability are non-negotiable. Fieldpiece is a trusted brand among technicians, and two of its most popular clamp meters are the SC440 and the SC640. While both are designed for professionals, they serve slightly different needs. In this article, we’ll compare the two side by side to help you decide which one best fits your workflow.
📋 Overview of the Fieldpiece SC440
The Fieldpiece SC440 is part of the Essential Series of clamp meters. It provides HVAC technicians with the essential features they need in a durable, rugged package. It’s designed for those who want dependable performance without the extra cost of advanced features.
Key highlights:
- Built-in temperature measurements
- Dual display for volts and amps
- Inrush current measurement
- Compact, rugged design
📋 Overview of the Fieldpiece SC640
The Fieldpiece SC640 belongs to the Advanced Series, offering more features for those who require a greater level of diagnostic capability. It builds on the functionality of the SC440, adding more measurement modes and extended ranges.
Key highlights:
- TRMS (True RMS) accuracy
- More detailed microamp readings (useful for flame sensors)
- Min/Max hold function
- Larger jaw opening for bigger conductors
🔍 Side-by-Side Comparison
Here’s a direct comparison between the SC440 and the SC640:
| Feature / Spec | Fieldpiece SC440 | Fieldpiece SC640 |
|---|---|---|
| Series | Essential | Advanced |
| True RMS | No | Yes |
| AC Current Range | Up to 400A | Up to 600A |
| Jaw Opening | 1 inch | 1.25 inch |
| Temperature Measurement | Yes | Yes |
| Microamps (DC) | Yes | Yes (greater sensitivity for flame sensors) |
| Inrush Current | Yes | Yes |
| Display | Dual display (volts & amps) | Dual display with min/max recording |
| Backlight | No | Yes |
| Safety Rating | CAT III 600V | CAT III 600V |
| Best For | HVAC techs who want essential features at lower cost | HVAC/electrical techs needing advanced diagnostics and higher accuracy |
✅ Pros and Cons
Fieldpiece SC440
Pros:
- Lower cost than SC640
- Durable and rugged design
- Covers all essential HVAC measurements
Cons:
- No True RMS
- Smaller jaw opening
- Fewer advanced diagnostic features
Fieldpiece SC640
Pros:
- True RMS for greater accuracy
- Larger jaw capacity
- Backlit display and min/max hold
- More sensitive microamp measurement
Cons:
- Pricier than SC440
- Slightly bulkier design
🏆 Verdict: Which One Should You Buy?
- Choose the Fieldpiece SC440 if you want a reliable, budget-friendly clamp meter that covers the basics without unnecessary extras.
- Choose the Fieldpiece SC640 if you need True RMS accuracy, advanced diagnostic features, and more flexibility for varied HVAC and electrical tasks.
Both models are rugged, trustworthy, and designed with technicians in mind—your choice ultimately depends on whether you need essential or advanced capabilities.