We used a newly purchased REV pneumatic hub in our bot this year. We found that the compressor was failing to run when the bot was enabled. This was an intermittent issue that would come and go. We finally isolated it to the connection of the pressure switch. When you pulled on the wires, the compressor would run. Letting go made the compressor stop. We swapped out the board for one scavenged from last year’s bot. I took it home, did some examination, and found that there was a cold solder joint between the connector and the ground connection. It took a ton of heat to get the joint to be good. I hypothesize that the ground connection is to a ground plane that acts as a heat sink to that joint. Not too much of a problem if the boards are batch soldered in an oven, but kind of tricky to resolder that joint by hand. Is anyone else experiencing similar issues with cold solders on these boards? If so, here’s how to fix it.
Note that repairs of this kind are permitted by rule R710M. "Devices may be repaired, provided the performance and specifications of the device after the repair are identical to those before the repair. "
I hate to say it because we use a lot of REV products but their pneumatic hub is too big of a pain to use. We have a couple of them and because they made the connectors so close together you have to use an uninsolated ferrule to install the wiring. They were supposed to be redesigning them but to my knowledge they haven’t. It made the call to not use pneumatics on our robot this year that much easier. Maybe its just one more thing rev has decided to not change like the 1" wall thickness on the 2x1s
We experienced intermittent problems with the compressor failing to run (using a Rev pneumatics hub) when we were in Houston last year. We had someone from Rev over in our pit trying to help us diagnose the issue (which we were very thankful for).
It was as you describe, if you pulled on the wire a bit then it would shut off.
The representative from Rev believed it was a problem with how we’d connected the wire (for reference we didn’t use ferrules). After he made many attempts to re-insert the wire, the problem seemed to go away.
This is another data point though, so thank you for sharing.
We had an issue during 2022 in Houston where our pneumatics wouldn’t fill up, and we isolated it to the pneumatics hub. Iirc it was fried somehow, despite being wired correctly. Our theory was that the humidity difference between Michigan and Texas caused some liquid seepage into the hub, frying the components after a bit of working around.
I’ll take a look to see if it was a cold solder joint when I find time, but we weren’t very impressed.
I took a look, and I didn’t see any cold solder joints, but there was 2022 ball fuz, no idea if that was introduced in the many times it got taken apart. There were still no obvious signs about why it broke.
