Southwire 21550T
#8 in AC/DCFull review
A true-RMS AC/DC clamp with handy jobsite touches, for electricians who don’t need inrush or a CAT IV rating.
Amazon $90.57$90.57
The Southwire 21550T rates 3.4 among AC/DC clamp meters; the Fluke 323 rates 3.0 among AC only ones. The Southwire 21550T costs $62.28 less ($90.57 vs $152.85).
Prices were last checked November 9, 2026. Product prices and availability are accurate as of that date and are subject to change; the price and availability shown on Amazon or the retailer's site at the time of purchase apply. As an Amazon Associate we earn from qualifying purchases.
Fluke 323
#5 in AC onlyFull review
A simple, well-built true-RMS AC clamp for electricians who want a Fluke for everyday panel and circuit checks.
Amazon $152.85$152.85
Scores side by side
These two sit in different type classes (AC/DC and AC only), and each is scored against the reference points for its own class, so a rating says how well each does among its own type peers. How we rank explains each factor.
| Factor weight | Southwire 21550T | Fluke 323 |
|---|---|---|
| Overall rating | 3.4/5 | 3.0/5 |
| Current range 15% | 46 400 A through the jaw | 46 400 A through the jaw |
| DC current 15% | 100 DC current to 400 A through the jaw | 0 no DC current |
| Safety rating 20% | 55 CAT III 600 V | 75 CAT IV 300 V / CAT III 600 V |
| Features 15% | 45 true RMS, non-contact voltage, temperature | 25 true RMS |
| Accuracy 10% | 50 current accuracy not published (neutral score used) | 67 2% of reading |
| Jaw opening 5% | 50 jaw opening not published (neutral score used) | 33 30 mm jaw |
| Warranty 10% | 0 warranty not published, scored as none | 50 2-year warranty |
| Price 10% | 74 $90.57 | 51 $152.85 |
Specifications
| Southwire 21550T | Fluke 323 | |
|---|---|---|
| Measurement | ||
| AC current (jaw) | 400 A | 400 A |
| DC current (jaw) | 400 A | No |
| Voltage | - | 600 V |
| Current accuracy | - | 2% of reading |
| Jaw opening | - | 30 mm |
| Safety | ||
| CAT rating | CAT III 600 V | CAT IV 300 V / CAT III 600 V |
| Features | ||
| True RMS | Yes | Yes |
| Inrush | - | No |
| LoZ mode | - | No |
| Non-contact voltage | Yes | No |
| Low-pass filter | - | No |
| Temperature | Yes | No |
| Phone app | - | No |
| Build | ||
| Weight | - | 265 g |
| Warranty | - | 2 years |