MIL-STD-461 CS115 Conducted Susceptibility EMC Testing
As a leader in EMC regulatory compliance testing, Keystone Compliance assists electronic equipment manufacturers with MIL-STD 461 EMC testing. Meeting the IEC, EN, and other MIL-STD-461 testing requirements can be challenging. Not only do we understand the challenges, but we help guide companies through the process. From concept through compliance, Keystone meets all of our customer’s needs under one roof.
Summary of EMC Regulatory Compliance CS115 Testing
This MIL-STD-461 standard EMC compliance test is applicable to all aircraft, space, ground system interconnecting cables, including power cables. The requirement is also applicable for surface ship and submarine subsystems and equipment when specified by procuring activity.
The equipment under testing (EUT) can not exhibit any malfunction. It also cannot show any signs of degradation of performance. Lastly, any deviations from specified indications, beyond tolerances indicated in the individual equipment are not allowed as well. This is only when subjected to a pre-calibration signal having rise and fall times, pulse width, and amplitudes at a 30 Hz rate for one minute.
Lastly, this MIL-STD-461 test method is used to verify the ability of the EUT to withstand impulse signals coupled onto EUT associated cabling.
Scope of MIL-STD 461 Compliance CS115 Testing
The basic setup for the equipment under testing must be maintained.
Next, the test equipment is calibrated. This is done by placing the injection probe around the center conductor of the calibration fixture. One end of the calibration fixture is terminated with a coaxial load. The other end is terminated with an attenuator connected to an oscilloscope with 50 oHm input impedance.
The equipment under testing is configured specifically. First, the injection and monitor probes are placed around a cable bundle interfacing with an EUT connector. To minimize errors, the same signal circuit that was used for calibration between the attenuator at the calibration fixture is maintained and connected to the circuit monitor probe. Additional attenuation may be used. Lastly, the injection probe is positioned 5 cm from the monitor probe.
Specific data from the MIL-STD-461 test method will be provided in the report. This will include information such as the date, time, location and test engineer. Other information may include tables showing statements of compliance with the requirement for the susceptibility evaluation.
Any susceptibility thresholds or oscilloscope photographs of injected waveforms will also be provided with the test data.
Military Standard Electromagnetic Compatibility EMC Testing Procedures
First, the MIL STD-461G testing equipment is turned on with ample time for stabilization.
Calibration is the next step in the EMC unintentional radiator procedure. The pulse generator source is adjusted for the rise time, pulse width, and pulse repetition rates specified in this compliance test.
Next, the signal applied to the calibration fixture is increased. This is done until the oscilloscope indicates that the current level specified in the requirement exists in the center conductor of the calibration fixture. The rise time and pulse width portion of the waveform are verified and the pulse generator amplitude is recorded.
The equipment under testing is then turned on and allowed sufficient time for stabilization. A susceptibility evaluation is performed. This is done by adjusting the pulse generator, applying a test signal, monitoring the EUT, and recording the peak current induced in the cable as indicated on the oscilloscope.
These steps are repeated on each cable bundle interfacing with each electrical connector on the EUT.
Keystone Compliance Offers Expert MIL-STD 461 Compliance Testing
In addition to CS115 testing, Keystone has a full scope of expertise including environmental and package testing such as temperature, vibration, and accelerated aging. Our team strives to give our customers more time and energy on product development instead of testing. Keystone has a full lab of test equipment which permits us to provide short lead times on scheduling.
For more information on general MIL-461 compliance and test standards, please visit the links below: