Short-circuit loop impedance meter with 0.01 Ω resolution
The AMZC-306 measures the fault-loop impedance ZL-PE, ZL-N and ZL-L with 0.01 Ω resolution in networks from 110/190 V to 400/690 V, calculates the prospective short-circuit current and measures without tripping RCDs rated above 30 mA.
Advantages
Resolution of 0.01 Ω
Loop impedance from 0.13 to 1999 Ω per IEC 61557 with 0.01 Ω resolution and high-current measurement up to 30 A, separating the resistive and reactive components of the loop.
Every LV network covered
Measurements in installations of 110/190 V, 115/200 V, 127/220 V, 220/380 V, 230/400 V, 240/415 V, 290/500 V and 400/690 V, over a voltage range of 100 to 750 V at 45-65 Hz.
No nuisance tripping
The ZL-PE RCD mode measures the loop without tripping residual-current devices rated above 30 mA, from 0.43 to 1999 Ω in the 100-440 V range.
Safe, verified connections
A contact electrode checks the correct connection of the PE terminal, the measurement continues when L and N are swapped and an overvoltage alarm protects the operator.
Field-ready autonomy
Four LR14 alkaline or NiMH batteries deliver more than 5000 measurements, with auto-off after 300 seconds, a 990-cell memory (3500 entries) and USB transfer to a PC.
Applications
- Verification of protection against electric shock in LV installations.
- Fault-loop measurements in industrial networks up to 690 V.
- Circuits protected by residual-current devices.
- Calculation of prospective short-circuit currents in distribution boards.
- Periodic inspections with documented results.
About the product
The AMZC-306 is rated CAT IV 600 V (CAT III 1000 V) with double insulation and IP54 protection and weighs 2 kg; it is supplied with the UNI-SCHUKO adapter, 1.2 m test leads, pin probes, crocodile clips, carrying case, USB cable, harness, NiMH battery pack, Z7 power adapter and calibration certificate, with 5 to 20 m leads and three-phase socket adapters as options.
Technical specifications
| Loop impedance | ZL-PE, ZL-N, ZL-L; resolution 0.01 Ω |
| Measuring range | 0.13-1999 Ω (1.2 m leads) per IEC 61557 |
| Accuracy | ±(5 % m.v. + 3 digits) to 19.99 Ω; ±(4 % + 3 digits) above |
| RCD mode | No tripping of RCDs >30 mA; 0.43-1999 Ω; 100-440 V |
| Networks | 110/190 V to 400/690 V; range 100-750 V; 45-65 Hz |
| Short-circuit current | Calculated for nominal voltage; R and X components |
| Voltage measurement | 0-750 V; 0.1 V resolution up to 250 V |
| Memory and interface | 990 cells (3500 entries); USB |
| Power supply | 4 × LR14 alkaline or NiMH; >5000 measurements |
| Safety | CAT IV 600 V (CAT III 1000 V); IP54 |
| Operating conditions | 0 to +45 °C; humidity 20-80 % |
| Dimensions and weight | 288 × 223 × 75 mm; 2 kg |
Frequently asked questions
Can it measure without tripping the RCD?
Yes. The ZL-PE RCD mode measures the loop impedance without tripping residual-current devices rated above 30 mA.
Which networks does it cover?
Installations from 110/190 V to 400/690 V, with a measuring voltage range of 100 to 750 V at 45-65 Hz.
Does it calculate the short-circuit current?
Yes. It calculates the prospective short-circuit current for the nominal voltage and displays the resistive and reactive components of the loop.
What accessories are included?
The UNI-SCHUKO adapter, 1.2 m test leads, probes, crocodile clips, carrying case, USB cable, harness, NiMH battery pack, Z7 power adapter and a calibration certificate.
How long do the batteries last?
More than 5000 measurements on one set of alkaline LR14 batteries, helped by automatic power-off after 300 seconds.
