Compact short-circuit loop impedance meter with IP67 housing
The AMZC-304 measures fault loop impedance in 230/400 V networks with 0.01 Ω resolution and up to 13.3 A of measuring current, calculates the prospective short-circuit current, verifies continuity of protective connections with ±200 mA and stores 990 results sent to the PC over Bluetooth.
Advantages
Loop with 0.01 Ω resolution
The standard-current 2p measurement covers 0.13 to 1999 Ω per EN 61557 with ±(5% m.v. + 3 digits), using up to 13.3 A at 400 V (7.6 A at 230 V) in three 10 ms periods.
Without tripping RCDs
The low-current mode measures ZL-PE from 0.5 Ω in circuits protected by RCDs of 30 mA or more, with the installation in service and no outages.
Fault current at a glance
From the impedance and the rated voltage, the meter calculates the prospective short-circuit current from 0.110 to 9999 A and separates the resistance RS and reactance XS components.
Continuity per EN 61557-4
Protective and equipotential connections are verified with a ±200 mA current from 0.12 to 400 Ω, and resistance with low current up to 1999 Ω.
Applications
- Verification of short-circuit protection in residential and office buildings.
- Industrial plants with fault currents up to 4.4 kA.
- Circuits protected by RCDs, measured without causing trips.
- Continuity checks of protective and equipotential conductors.
About the product
The AMZC-304 is one of the most compact loop meters in its class: 220 × 102 × 61 mm and about 0.8 kg, powered by four AA batteries or NiMH accumulators. It works in 220/380 V, 230/400 V and 240/415 V networks (180…460 V range) at 45…65 Hz, measures voltage from 0 to 500 V and frequency, and supports measurement with the L and N conductors swapped.
It complies with the EN 61557 series and the CAT IV 300 V (CAT III 600 V) category with double insulation. The 990-result memory downloads to the computer over Bluetooth, where the reader software archives and documents the verifications; the WS-05 UNI-Schuko adapter speeds up measurements at socket outlets.
Available accessories: WS-05 adapter with angular UNI-Schuko plug, 1.2 m test leads (red, blue and yellow), pin probes, crocodile clip, carrying case, straps, batteries and a factory calibration certificate; optionally the WS-03, WS-04 and WS-07 adapters, AGT three-phase adapters from 16 to 63 A and 5, 10 and 20 m leads.
Technical specifications
| Loop impedance | 0.13…1999 Ω per EN 61557; resolution from 0.01 Ω |
| No-trip mode (RCD) | From 0.5 Ω in circuits with RCDs ≥30 mA |
| Measuring current | Max. 13.3 A at 400 V; 7.6 A at 230 V (3 × 10 ms) |
| Short-circuit current | Calculated: 0.110…9999 A; RS and XS components |
| Continuity | ±200 mA per EN 61557-4; 0.12…400 Ω |
| Voltage and frequency | 0…500 V; 45.0…65.0 Hz |
| Memory and interface | 990 results; Bluetooth |
| Safety | CAT IV 300 V (CAT III 600 V); IP67 |
Frequently asked questions
Which networks can it measure in?
In 220/380 V, 230/400 V and 240/415 V networks with working voltages from 180 to 460 V and a frequency of 45 to 65 Hz.
Does it trip RCDs while measuring?
Not in RCD mode: the low-current measurement avoids tripping RCDs of 30 mA or more, keeping the installation in service.
Does it calculate the prospective short-circuit current?
Yes. From the measured impedance and the rated voltage it indicates 0.110 to 9999 A, with the resistance and reactance components.
Does it withstand site conditions?
Yes. The sealed IP67 housing, backlit keyboard and AA battery power make it fit for outdoor and harsh environments.
