How to fix a problem spike

[Jon Stratis]

Originally Posted by jwakeman

I believe I found a bad spike last night while trying to get our compressor running. The behavior i saw from the spike is similar to what the original post described. Here is what my experience was:

1. Using 20 Amp snap breaker in the spike. Using the Compressor class in WPILib. Before the robot was enabled, solid orange LED on the spike. Once the robot was enabled the Compressor code would turn on the relay on the DSC (confirmed, little green light lit up as expected) that the spike was connected to. This resulted in the LED on the spike turning off (no color).

2. Removed the compressor leads from the output side of the spike. No change. Spike LED still off.

3. Removed the pwm cable from the spike. LED turn RED. Measured -10V on the output of the spike.

Replaced the spike. All worked fine. I did notice the pins on the pwm were pretty mangled when i removed it from the spike the first time (step 3 above) and it is possible not all three pins were seated correctly and this may have had something to do with the failure of the spike.

Could it have something to do with the way the PWM cable was seated in the Spike? I haven't opened one up for a couple of years, but if the pins find their way to contacting control components that they shouldn't, it possible to fry something with an unexpected 5V signal...