Our power distribution board started making noises. It makes both a mid level hum and a separate crackling or arcing noise. All lights are correct and everything else seems to work.
Anyone else experienced anything like this?
From 3-FRC Control System Component Datasheets
When under light load, the 24V boost supply will emit an audible whining noise and have a larger voltage ripple. This is an artifact of its power saving mode, and should not cause concern.
There was some similar discussion on the usfirst forums before. Take a look here.
Hope this helps,
Jason Law
hum and crackling noises sound like a problem to me. Start by removing all cricuit breakers and then turn the power back on. If the hum and crackling have gone away, try installing breakers one at a time. Breakers do go bad and are known to have manufacturing defects. The crackling noise could be a bad contact in a breaker. If the hum remains with all breakers out, doulbe check your outboard voltage wiring to the camera, CRIO, and sidecars. You might have crossed connections, which is producing a short on the output of one of these independent power supplied internal to the power distro board.
Something else to check is that if you have the camera installed its mounting is electrically isolated from the rest of the robot. We had a loose wire touching the frame and causing sparks before we discovered and corrected this problem.
Does anyone with perfect pitch want to identify that pitch? I’ll post it on Monday if no one else does… (oh I’m not perfect pitch but I’ll identify it)
The frequency is a function of battery voltage and load. The load is a function of what the bridge or cRIO are doing. You can actually hear it sing a boot melody if you listen close enough.