The Testo 770-1 is a True RMS clamp meter with a fully retractable pincer arm, designed for measuring current on tightly packed cables in confined spaces. A standard clamp meter has a rigid jaw that needs to fit around a cable from the side, which can be impossible in a packed consumer unit or control panel where cables sit close together. The 770-1's pincer arm folds back into the body, so the fixed part can be positioned behind a single cable before the retractable section slides out to complete the clamp — reaching cables a standard jaw simply can't get to.
The meter is TRMS, giving accurate readings on the non-sinusoidal waveforms produced by inverters and VFDs, and automatically detects whether a circuit is AC or DC along with which measurement mode to use — the same principle used across the Testo 760 Multimeter range. It measures AC/DC current from 0.1A to 400A via the clamp, and AC/DC voltage from 1mV to 600V via measuring leads, along with resistance up to 40MΩ, frequency, capacitance, continuity and diode testing. Inrush current measurement captures the peak starting current surge at motor and compressor start-up.
Readings are shown on a two-line backlit display with 4,000 counts, so two values can be viewed at once. It's rated CAT IV 600V, and comes with measuring cables and batteries included.
The retractable pincer arm solves a genuine practical problem — getting a clamp around a single cable in a packed consumer unit or control panel, where a rigid jaw simply can't reach. TRMS accuracy matters on the inverter and VFD-driven equipment increasingly common in HVAC systems, and inrush current measurement captures the starting surge at motor and compressor start-up, which a standard reading would miss. Automatic parameter detection carries over the same reliability benefit seen on the Testo 760 Multimeter range, reducing the chance of a measurement being taken in the wrong mode.
Order the Testo 770-1 TRMS Clamp Meter online today.
| Brand | Testo |
|---|---|
| Part Number | 0590 7701 |
| Product Type | TRMS Clamp Meter |
| True RMS | Yes – 0.8% Basic Accuracy |
| Clamp Type | Retractable Pincer Arm |
| AC Current (Clamp) | 0.1 – 400A |
| DC Current (Clamp) | 0.1 – 400A |
| AC Voltage | 1mV – 600V |
| DC Voltage | 1mV – 600V |
| Resistance | 0.1Ω – 40MΩ |
| Frequency | 0.001Hz – 10kHz |
| Capacitance | 0.001μF – 100μF |
| Inrush Current | Yes |
| Auto Parameter Detection | Yes – AC/DC, Resistance, Capacitance, Continuity, Diode |
| Hold / MIN/MAX | Yes / Yes |
| Display | Two-Line Backlit LCD, 4,000 Counts |
| Safety Rating | CAT IV 600V |
| Standards | EN 61326-1, EN 61140 |
| Certifications | TÜV, CSA, CE |
| Operating Temperature | -10°C to +50°C |
| Storage Temperature | -15°C to +60°C |
| Dimensions | 243 x 96 x 43mm |
| Weight | 378 g |
| Included | Measuring Cables, Batteries |
| Warranty | 2 Years |
