Loop impedance meter for networks up to 400/690 V
The AMZC-305 measures short-circuit loop impedance with 0.01 Ω resolution in networks from 110/190 V to 400/690 V — a 100 to 750 V working range that few meters cover — with a measuring current of up to 30 A, a no-trip RCD mode, a 990-record memory and a USB connection to the PC.
Advantages
Eight rated networks, one meter
It measures in 110/190, 115/200, 127/220, 220/380, 230/400, 240/415, 290/500 and 400/690 V networks, automatically distinguishing phase from line voltage, with ZL-L up to 750 V.
High current for firm readings
The high-current measurement of up to 30 A yields readings from 0.13 to 1999 Ω per IEC 61557 with ±(5% m.v. + 3 digits) in the low range, with the R and X components and the short-circuit current calculation.
RCDs without tripping
The ZL-PE RCD mode measures from 0.43 Ω without tripping RCDs above 30 mA, in networks from 100 to 440 V and also with the L and N conductors swapped.
Voltage up to 750 V
The built-in voltmeter reads from 0 to 750 V with 0.1 V resolution up to 250 V and an overvoltage alarm, available in every loop function.
Applications
- Verification of short-circuit protection in 500 and 690 V industrial networks.
- Low-voltage installations in housing, offices and workshops.
- Measurements at socket outlets with the UNI-Schuko adapter.
About the product
The AMZC-305 is a loop impedance meter designed for those who work across networks of different voltages: from the 110/190 V of some industrial plants to the 400/690 V of heavy industry. The contact electrode verifies the connection of the PE terminal, measurement is possible with L and N swapped and the working frequency covers 45 to 65 Hz.
With double insulation per IEC 61010-1, a CAT IV 600 V (CAT III 1000 V) category and an IP54 housing, it runs on four AA alkaline batteries or accumulators and switches off automatically after 120 seconds of inactivity. Its 260 × 190 × 60 mm and 2.2 kg include an LED-backlit segment display.
Available accessories: 1.2 m banana test leads (red, blue and yellow), pin probes, K02 crocodile clips, L4 carrying case, USB cable, straps, batteries and a calibration certificate; optionally the WS-05 UNI-Schuko adapter, the WS-01 probe with START button, AGT three-phase adapters from 16 to 63 A and 5, 10 and 20 m leads.
Technical specifications
| Loop impedance | ZL-PE, ZL-N, ZL-L: 0.13…1999 Ω per IEC 61557 |
| Supported networks | From 110/190 V to 400/690 V (100…750 V range); 45…65 Hz |
| Measuring current | High current, up to 30 A |
| No-trip mode (RCD) | From 0.43 Ω without tripping RCDs >30 mA |
| Voltage measurement | 0…750 V; 0.1 V resolution up to 250 V |
| Memory and interface | 990 cells (3500 records); USB |
| Power supply | 4 AA batteries or accumulators; >3000 measurements |
| Safety | CAT IV 600 V (CAT III 1000 V); IP54 |
Frequently asked questions
What sets it apart from other loop meters?
Its network range: it measures from 110/190 V to 400/690 V — working voltages of 100 to 750 V — essential in industry with 500 or 690 V networks.
Can it measure without tripping RCDs?
Yes. The ZL-PE RCD mode measures from 0.43 Ω in circuits with RCDs above 30 mA without causing them to trip.
What accuracy does the loop measurement offer?
±(5% m.v. + 3 digits) up to 19.99 Ω and ±(4% m.v. + 3 digits) above, with 0.01 Ω resolution and short-circuit current calculation.
Does it indicate the loop components?
Yes. Besides the impedance module, it shows the resistive and reactive components and the short-circuit current calculated for the rated voltage.
