Pyrotechnic Cable Cutter at Cryogenic Temperature

This article presents and explains the pyro-cable cutter test setup developed by ALTER Optoelectronics and New Technologies laboratory. The design and development of the test setup has taken into consideration all the requirements of samples. In this case, we followed a reference document, MIL-STD-202, to be applicable in space usage.

So, we had to test whether all samples detonated in a different test condition; the most critical test was firing the samples at -100ºC.

Test setup, procedures, and results

At first, was necessary to design software to control our oscilloscope, and a precision source meter and we need to use a cryogenic chamber. And we were ready to test the samples.

Then, all samples were serialized and characterized at room temperature and at -100ºC, after that the samples were distributed in different groups in accordance with the test requirements which can observe in the following graph.

We preselected the samples for a different detonation test because we had four types of tests, detonation and non-detonation in 2 different temperatures with the same electrical test conditions.

• At room temperature and at -100ºC, with a short electrical pulse 1.2A, 2ms, and had to verify of the pyro-cutter was activated.

Figure 7: Short pulse detonation

• At room temperature and -100ºC with short pulses sequence 0.4A x 10 pulses and had to verify all samples were not detonated.

Figure 8: Short pulse sequence

Most samples passed all the tests, but three samples showed problems because the cables don’t resist a very low temperature.

A problem with these tests was some cables; at -100ºC, we could not bend or manipulate a cable because it could wreck the cover.