Quick look:
- Tests rapid transitions from hot to cold environments or vice versa
- A rapid transition is defined as at least 10°C per minute
- Includes four different procedures: 1A through 1D
About MIL-STD-810 Method 503
Method 503 is a temperature shock test that simulates the transition from a hot environment to a cold environment very rapidly. The test defines high-speed transitions as 10°C per minute, or at least 10°C per minute, because you can actually have much more rapid transitions.
These are surface tests focused on the outside of a unit. You’re looking for shattered glass or thermal coefficient expansion changes that can:
- Deform materials
- Crack materials
- Damage insulators
- Alter the performance of the electrical system
In the computer industry, we’re looking at what’s happening to the circuit board components and what’s being damaged by very, very rapid transitions in temperature.
The test is centered around four different procedures, 1A through 1D.
- 1A is a half cycle, which goes from cold to hot or vice versa.
- B is a full cycle, which goes hot to cold and back to hot or vice versa.
- C encompasses multiple cycles. The spec recommends at least three, but you can do more.
- Cycle D testing is done to more extreme levels and involves multiple shocks.
We simulate rapid temperature changes that mirror dropping a piece of equipment out of a C-141 on an airdrop, or taking it out of an air-conditioned facility into a desert environment to determine if and how well it can withstand those extremes.
That’s why we look for any changes to the performance or any damage to the equipment. We look especially at the outer surface areas because those are the ones that are exposed to the most rapid change.
To conduct this test, you want to make sure you specify:
- Test temperature
- Transition duration
- How long you want to have the system at that temperature, or the “dwell” time
- Number of cycles
- Transfer time in terms of door open/door closed
- How often you are going to check the performance of the unit
Just like every other test MIL-STD-810 test, this method is intended to be highly tailored for the application. We recommend putting some thought into exactly what you want to test with Method 503 before getting started. Otherwise, you will get some results, but you won’t be able to derive valuable insights with real application.
