M Precision Laboratories ECAT Lightning Test System Level 5

RTCA/DO-160 Section 22 offers test procedures to determine whether the EUT can operate as specified during and/or after various lightning induced transient waveforms are injected into connector pins, interconnecting cables, and power leads using pin injection, and/or cable bundle tests. The pin injection method is normally used to show damage tolerance, while the cable bundle tests are normally used to show upset tolerance. Pin Injection During pin injection testing, the EUT is normally powered, so that the circuits being tested are biased as they would be in normal operation. The test level is defined as an open circuit voltage (Voc) with a specified source impedance from the generator. Cable Bundle Tests Cable Bundle Tests are performed using either Cable Induction or Ground Injection to couple the transient waveforms into the interconnecting cable bundles and power leads. The cable induction test method uses an injection probe to induce the transient waveforms into interconnecting cables and power leads. The ground injection method is very similar to the cable induction method, except that the transient waveform is applied between the EUT case and the ground plane. Cable Bundle tests for RTCA/DO-160 Section 22 may be performed using the Single Stroke method only or using a combination of the Single Stroke, Multiple Stroke, and Multiple Burst methods. The Single Stroke test method is designed to represent the internal aircraft wiring response to the most severe external aircraft lightning strike. The Multiple Stroke test method is designed to represent the induced effects to internal aircraft wiring in response to an external aircraft lightning strike that is composed of a first return stroke immediately followed by multiple return strokes. The Multiple Burst test method is designed to represent the induced effects to internal aircraft wiring in response to an external aircraft lightning strike of a multiple burst nature. Equipment

MIL-STD-461G CS117 applies to all safety-critical equipment interconnecting cables, including complete power cables, and individual high side power leads. MIL-STD-461G CS117 is also applicable to non-safety critical equipment with interconnecting cables/electrical interfaces that are part of or connected to equipment performing safety-critical functions. It may apply to equipment performing non-safety critical functions when specified by the procuring activity. MIL-STD-461G CS117 also has limited applicability to surface ship equipment which have cables routed above deck.   Test Equipment Lightning transient generator Injection Transformers Oscilloscope Current monitor probes Attenuators Voltage Probe LISNs   Procedures The test procedures shall be as follows: a. Turn on the measurement equipment and allow sufficient time for stabilization. b. Calibration. Perform the following procedures using the calibration setup for waveform verification. (1) Connect the transient generator to the primary input of the injection transformer. (2) For each waveform, at the designated test level (VT or IT), record the voltage waveform with the calibration loop open or the current waveform with the calibration loop shorted, as applicable. Verify that each waveform complies with the relevant waveshape parameters shown in Figure CS117-1 through Figure CS117-6. The transient generator doesn't need to produce the associated voltage or current limit level (VL or IL) and waveshape. However, if the transient generator is capable of reaching the designated limit level (VL or IL), record and verify the limit waveform at that generator setting. (3) For the Multiple Stroke and Multiple Burst tests, also verify the applicable pulse patterns and timing identified in Figure CS117-7 and Figure CS117-8. (4) Reverse the transient generator polarity and repeat 5.15.3.4b(2) through 5.15.3.4b(3). c. EUT testing. (1) Turn on