No photo yet
Extech (Teledyne FLIR)
Extech MA640 True RMS AC/DC Clamp Meter with NCV
—
Best Clamp Meters · head-to-head
Extech MA640 True RMS AC/DC Clamp Meter with NCV vs Southwire 21050T / 21550T 400A True RMS AC/DC Clamp Meter
A sourced, side-by-side comparison. Extech MA640 True RMS AC/DC Clamp Meter with NCV is cheaper at —. Every spec and price links to its source.
No photo yet
Southwire
Southwire 21050T / 21550T 400A True RMS AC/DC Clamp Meter
—
Full spec sheet
✓ marks the stronger figure where "more" — or "less", for price and weight — is unambiguously better.
| Spec | Extech MA640 True RMS AC/DC Clamp Meter with NCV | Southwire 21050T / 21550T 400A True RMS AC/DC Clamp Meter |
|---|---|---|
| US price | — | — |
| Brand | Extech (Teledyne FLIR) | Southwire |
| Released | — | — |
| Ac current range | 60.00 A / 600.0 A | 400 A |
| Dc current range | 60.00 A / 600.0 A | 400 A (per user-facing marketing copy and verified purchaser reviews on southwire.com describing DC clamp-amp use; exact numeric DC accuracy table not published on the fetched product page) |
| Jaw opening | 1.5 in (40 mm), conductors up to 500 MCM | — |
| Ac dc voltage range | AC 6.000V/60.00V/600.0V; DC 600.0mV/6.000V/60.00V/600.0V | — |
| True rms | Yes | Yes |
| Resistance continuity | 600.0Ω to 60.00MΩ, with continuity | — |
| Capacitance | 40.00nF to 4000µF | Yes |
| Temperature | -4°F to 1400°F (-20°C to 760°C), Type K | Yes |
| Cat safety rating | CAT III 600V | CAT III 600V |
| Display count | 6000 | — |
Sources — Extech MA640 True RMS AC/DC Clamp Meter with NCV: flir.com (verified 2026-08-05). Southwire 21050T / 21550T 400A True RMS AC/DC Clamp Meter: southwire.com (verified 2026-08-05).
What's the difference between the Extech MA640 True RMS AC/DC Clamp Meter with NCV and Southwire 21050T / 21550T 400A True RMS AC/DC Clamp Meter?
Where the two actually differ on the specs we track (4 of 10). Matching specs are omitted.
- Ac current range: Extech MA640 True RMS AC/DC Clamp Meter with NCV 60.00 A / 600.0 A vs Southwire 21050T / 21550T 400A True RMS AC/DC Clamp Meter 400 A
- Dc current range: Extech MA640 True RMS AC/DC Clamp Meter with NCV 60.00 A / 600.0 A vs Southwire 21050T / 21550T 400A True RMS AC/DC Clamp Meter 400 A (per user-facing marketing copy and verified purchaser reviews on southwire.com describing DC clamp-amp use; exact numeric DC accuracy table not published on the fetched product page)
- Capacitance: Extech MA640 True RMS AC/DC Clamp Meter with NCV 40.00nF to 4000µF vs Southwire 21050T / 21550T 400A True RMS AC/DC Clamp Meter true
- Temperature: Extech MA640 True RMS AC/DC Clamp Meter with NCV -4°F to 1400°F (-20°C to 760°C), Type K vs Southwire 21050T / 21550T 400A True RMS AC/DC Clamp Meter true