LI-3P-4X Series – Three-Phase LISN for MIL-STD-461 (CE102)
The Com-Power LI-3P-4X series consists of four models of four-conductor, 50Ω/50 μH Line Impedance Stabilization Networks (LISNs) purpose-built for CE102 power-line conducted emissions testing per MIL-STD-461D/E/F/G. Covering current ratings from 16 A to 100 A per phase, these LISNs operate across the 10 kHz to 10 MHz frequency range required by the military standard and support 50/60 Hz, 400 Hz, and 800 Hz AC power systems as well as DC power. All models support both Delta and Wye three-phase configurations, include remote fiber optic line switching via the RLI V2.0 interface, a built-in transient limiter, and air-core inductors to prevent saturation.
Model Comparison
| Specification |
LI-3P-416 |
LI-3P-432 |
LI-3P-463 |
LI-3P-4100 |
| Current Rating (per phase) |
16 A |
32 A |
63 A |
100 A |
| Frequency Range |
10 kHz – 10 MHz |
| Network Type |
50Ω, 50 μH, Four-Conductor |
| Standards Compliance |
MIL-STD-461D/E/F/G |
| Insertion Loss (10 kHz – 150 kHz) |
< 26 to < 21 dB |
< 26 to < 21 dB |
< 26 to < 21 dB |
< 26 to < 21 dB |
| Insertion Loss (150 kHz – 10 MHz) |
< 21 dB |
| Max AC Voltage (line-to-line, 50/60 Hz) |
865 Vrms |
| Max AC Voltage (line-to-ground, 50/60 Hz) |
500 Vrms |
| Max AC Voltage (line-to-ground, 400 Hz) |
270 Vrms |
| Max AC Voltage (line-to-ground, 800 Hz) |
135 Vrms |
| Max DC Voltage |
600 V DC |
| Power Connector Rating |
25 A |
50 A |
100 A |
100 A |
| RF Measurement Port |
50Ω N-Type (Female) |
| Remote Interface |
RLI V2.0 via Fiber Optic |
| Transient Limiter |
Built-In |
| Cooling |
Louvered Side Panels + 2 Internal Fans (15 VDC) |
| Dimensions (H × W × D) |
17.36″ × 17.79″ × 13.04″ |
17.36″ × 17.79″ × 17.48″ |
17.36″ × 17.79″ × 17.48″ |
17.36″ × 17.79″ × 20.78″ |
| Weight |
41.2 lbs (18.7 kg) |
51.7 lbs (23.5 kg) |
59.2 lbs (26.9 kg) |
70.9 lbs (32.2 kg) |
| Warranty |
Three Years |
LI-3P-4X vs. LI-3P-1X – Key Differences
While both the 4X and 1X series are three-phase, 50Ω/50 μH LISNs with identical current ratings (16, 32, 63, and 100 A), they are designed for different test standards and should not be used interchangeably:
| Parameter |
LI-3P-4X (Military) |
LI-3P-1X (Commercial) |
| Standard |
MIL-STD-461D/E/F/G |
CISPR 16-1-2 / ANSI C63.4 |
| Test Method |
CE102 |
Conducted Emissions (FCC / CE) |
| Frequency Range |
10 kHz – 10 MHz |
150 kHz – 30 MHz |
| 400 Hz / 800 Hz AC Support |
Yes (military aircraft power) |
No (50/60 Hz only) |
| Insertion Loss |
< 26 to < 21 dB |
< 11 dB |
| Cooling Fans |
All models (15 VDC powered) |
63 A and 100 A models only |
Important: MIL-STD-461 and CISPR 16-1-2 define different LISN circuit topologies and calibration requirements. A 4X-series LISN must not be used for CISPR/ANSI testing and vice versa. Always select the LISN series that matches the applicable test standard for the EUT.
How to Choose the Right Model
All four models share identical electrical performance and differ only in their maximum continuous current rating per phase. Select based on the EUT’s maximum per-phase current draw:
| Model |
Best Suited For |
Typical EUT Examples |
| LI-3P-416 (16 A) |
Low-power military three-phase equipment up to 16 A per phase |
Military communications equipment, field-deployable control units, small shipboard electronics, portable military power supplies |
| LI-3P-432 (32 A) |
Medium-power military three-phase equipment up to 32 A per phase |
Shipboard HVAC systems, military ground vehicle power electronics, medium radar subsystems, avionics power converters |
| LI-3P-463 (63 A) |
High-power military three-phase equipment up to 63 A per phase |
Large shipboard motor drives, aircraft ground support equipment, military industrial machinery, high-power UPS for defense installations |
| LI-3P-4100 (100 A) |
Very high-power military three-phase equipment up to 100 A per phase |
High-capacity shipboard power distribution, large aircraft ground power units, heavy military vehicle propulsion electronics, directed-energy weapon power systems |
Selection Rule: Always choose a LISN with a current rating that meets or exceeds the maximum continuous per-phase current draw of the EUT. Operating a LISN beyond its rated current can cause overheating and damage the internal inductors.
Real-World Applications
| Application |
Description |
| Military Shipboard Equipment |
Naval vessels rely on three-phase power for propulsion drives, weapons systems, and HVAC. CE102 testing with LI-3P-4X LISNs ensures these systems do not introduce conducted interference onto shared shipboard power buses, which could disrupt critical communications or navigation. |
| Aircraft & Avionics (400 Hz / 800 Hz) |
Military aircraft use 400 Hz (and sometimes 800 Hz) three-phase AC power. The LI-3P-4X series is rated for these frequencies, making it suitable for testing avionics power converters, flight control actuators, and aircraft ground support equipment under MIL-STD-461. |
| Ground Vehicle Power Systems |
Military ground vehicles increasingly use three-phase electric drive systems and high-power electronics. The LI-3P-432 and LI-3P-463 handle the mid- to high-current demands typical of these platforms during CE102 compliance testing. |
| Defense Contractors & Test Laboratories |
MIL-STD-461 compliance is mandatory for defense procurement. Test labs and contractors performing CE102 evaluations on three-phase military subsystems need dedicated MIL-compliant LISNs—the LI-3P-4X series fulfills this requirement across the full 10 kHz to 10 MHz range. |
| Power Generation & Distribution |
Military-grade three-phase generators, power distribution panels, and frequency converters must pass CE102 limits before deployment. The LI-3P-4100 provides 100 A capacity for testing the largest power units. |
| Directed-Energy & High-Power Radar |
Advanced defense systems such as directed-energy weapons and high-power radar arrays draw heavy three-phase current and produce significant conducted EMI. The 63 A and 100 A models accommodate these demanding test scenarios. |
Test Setup Overview (MIL-STD-461 CE102)
The CE102 test method measures conducted emissions on each power lead of the EUT against frequency-dependent limits. The setup places the LISN between the power source and the EUT on a ground reference plane inside a shielded enclosure:
- Place the LISN on the ground reference plane. The unpainted mounting plate must make direct metal-to-metal contact with the conductive ground plane to establish a low-impedance earth connection.
- Connect the power source to the LISN Power Input port. Wire the three-phase supply (L1, L2, L3, Neutral, and Protective Earth) to the color-coded input terminals using the supplied socket plug connectors. Ensure voltage and frequency are within the LISN’s ratings (50/60 Hz, 400 Hz, or 800 Hz AC, or DC).
- Connect the EUT to the LISN Power Output port. Wire the EUT power cable using the supplied plug pin connectors. Keep EUT power leads as short as practical per MIL-STD-461 test setup requirements.
- Connect the RF measurement port to the EMI receiver. Use a coaxial cable with an N-type connector to link the LISN’s 50Ω measurement port to the receiver. The built-in transient limiter protects the receiver’s input.
- Power the cooling fans. Connect the 15 VDC adapter to the rear-panel fan power jack. All LI-3P-4X models include two user-controlled internal fans to manage heat during high-current operation.
- Set up the Remote LISN Interface (RLI V2.0). Connect the fiber optic cable between the LISN and RLI V2.0 unit, and connect the RLI V2.0 to the test PC via USB for automated line switching. Alternatively, use front-panel push-buttons for manual selection.
- Select the line under test and perform the CE102 measurement. When a line is selected, the remaining lines are automatically terminated into 50Ω. Measure conducted emissions on each power lead (L1, L2, L3, and N if applicable) across the 10 kHz to 10 MHz range, comparing results to the CE102 limit curve.
Tip: MIL-STD-461 requires the LISN to be placed within the shielded enclosure and connected to the facility ground reference plane. Verify that bond strap impedance is sufficiently low before beginning measurements.
Key Features Across All LI-3P-4X Models
| Feature |
Description |
| Air-Core Inductors |
Prevent magnetic saturation and permeability variation, ensuring accurate impedance regardless of DC or AC current level. |
| Built-In Transient Limiter |
Protects the RF input of the measuring instrument from damaging voltage transients and reduces out-of-band emissions with internal low-pass and high-pass filters. |
| 400 Hz and 800 Hz AC Support |
Rated for military-standard power frequencies used in aircraft and certain shipboard systems, in addition to standard 50/60 Hz and DC. |
| Remote Line Switching (RLI V2.0) |
Fiber optic–controlled switching between L1, L2, L3, and N enables automated CE102 test sequences without manual intervention at the LISN. |
| Local Line Selection |
Front-panel push-buttons allow direct, manual selection of the line under test when remote operation is not required. |
| Internal 50Ω Termination |
Non-selected lines are automatically terminated into 50Ω, maintaining proper impedance on all lines during measurement. |
| Forced-Air Cooling (All Models) |
Two user-controlled internal fans (powered by a separate 15 VDC adapter) provide active cooling during extended high-current testing. |
| Individual Calibration |
Each unit is individually calibrated with impedance and insertion loss data per MIL-STD-461. ISO 17025 accredited calibration is available upon request. |
Included Accessories
Every LI-3P-4X LISN ships with the following items:
| Accessory |
Quantity |
| Plug Socket Connectors (for Power Input Cable) |
5 |
| Plug Pin Connectors (for EUT Power Cable) |
5 |
| RLI V2.0 Remote LISN Interface Unit |
1 |
| Fiber Optic Cable (10 m) |
1 |
| AC Power Adapters (6 VDC, 500 mA) – for remote interface |
2 |
| AC Power Adapter (15 VDC, 500 mA) – for cooling fans |
1 |
Optional Accessories: LIA-COAX-E Coaxial Adapter with Plug Pins for LISN EUT Port • LIA-COAX-M Coaxial Adapter with Plug Sockets for LISN Mains Port
Contact Us
Get a Quote
