Selecting an AMN/LISN for conducted emissions: check the network before the current rating

When planning conducted-emissions testing, a procurement list often starts with current capacity and plug type. Both matter, but they are not enough to select an artificial mains network (AMN), also commonly described as a line impedance stabilization network (LISN). A more reliable sequence is to identify the port under test and the test method, then check the network characteristics, measurement frequency range and electrical ratings.

Separate the test method from the equipment specification

IEC’s public description of CISPR 16-1-2:2014+AMD1:2017 identifies it as a basic EMC standard covering the characteristics and performance of measurement equipment, including artificial mains networks and current and voltage probes. Measurement methods are covered by the CISPR 16-2 series. A quotation stating compliance with CISPR 16-1-2 therefore does not, by itself, establish which network a particular product and port require. Before procurement, record the applicable product standard and edition, port category, supply arrangement and intended method, so the laboratory can confirm the configuration. This article does not infer product-specific mandatory requirements from a standard’s abstract.

Check the impedance network, even when frequency ranges overlap

Consider two publicly documented manufacturer examples. The R&S ENV216 is a two-line V-network for single-phase equipment under test, specified for 9 kHz to 30 MHz with a simulated impedance of (50 μH + 5 Ω) in parallel with 50 Ω. The Schwarzbeck NNBM 8124 is a single-path vehicle AMN, specified for 0.1 MHz to 150 MHz with an impedance of (5 μH + 1 Ω) in parallel with 50 Ω. These models illustrate specification differences; neither is being recommended for every project.

Operation over a shared frequency interval does not establish interchangeability, nor does a matching connector. Put network form, impedance characteristics, number of paths and applicable method together in the comparison sheet. A wider frequency range has procurement value only when the equipment also suits the intended method.

Read ratings together with their conditions

Distinguish continuous current capability from time-limited capability. The current NNBM 8124 manufacturer page lists 70 A continuous and 100 A for a limited time; the latter must not be treated as continuous test capacity. It also lists separate voltage ceilings for DC, 50/60 Hz AC and 400 Hz AC, illustrating why a voltage rating needs its supply conditions. Obtain the relevant duration, environmental conditions and restrictions from the current manual for the purchased model or written confirmation, rather than deriving them from a single maximum value.

Current capability can also differ within one product family. The ENV216 manufacturer page lists 16 A for the German-connector model and 10 A for the China/Australia-connector model. A purchase order stating only the family name or “up to 16 A” can conceal the difference in the actual ordered variant. Specify the power connector, order number and continuous rating together. If the quotation includes only a family overview, request a data sheet for the selected configuration. At acceptance, check the nameplate and accompanying documents against that configuration to avoid a specification mismatch between the order and delivery.

Include delivery evidence in the procurement checklist

Organize technical confirmation into three groups: the product, port, standard edition and method; the complete model designation with its network, frequency range and supply-rating conditions; and the calibration documentation, operating manual and site safety conditions. Calibration documentation should identify the equipment actually delivered and address the planned operating range, rather than merely provide a certificate with unspecified coverage.

These are procurement checks, not new universal acceptance limits. Qualified personnel should handle mains or high-voltage connections, protection and commissioning according to the equipment manual and site safety requirements. The final question is whether the network can perform the planned test under a defined method and operating conditions, not merely whether it can power the sample.

References

IEC — CISPR 16-1-2:2014+AMD1:2017 CSV, Edition 2.1
https://webstore.iec.ch/en/publication/61924

Rohde & Schwarz — R&S ENV216 Two-line V-network, product page
https://www.rohde-schwarz.com/nl/products/test-and-measurement/conducted-testing/rs-env216-two-line-v-network_63493-9775.html

Rohde & Schwarz — ENV216 Data Sheet, Version 06.00, November 2025
https://scdn.rohde-schwarz.com/ur/pws/dl_downloads/pdm/cl_brochures_and_datasheets/data_sheet/5214_0299_32/ENV216_dat_en_5214-0299-32_v0600.pdf

Schwarzbeck — NNBM 8124 Single Path Vehicle AMN (LISN), product page
https://www.schwarzbeck.com/lisn/v-lisn/lisn-automotive-cispr-25/lisn-cispr-25-iso-7637/nnbm-8124/