2018-07-10, 12:44 PM
The case has already been in use for a year or so, and I usually just keep it running all the time on the boat. It gets a little warm, but it has never been a problem.
However, one of the reasons I decided to tear this build down and do it again was because I wanted to put in a new 3B+. I had it working on the bench, not mounted, for several days. One day I came in to look at it and it was dead, red light was on but it wouldn't boot from anything. I don't know what happened, it could've just been the board getting laid down on a screw or something and it got shorted somehow, but I did notice the board got REALLY hot. I had cooling fins on the processor and the LAN chip, but didn't have anything for the WiFi shield (the one with the RPI logo on it). The WiFi shield got really hot as well. I did notice that some of the newer cooling kits for the 3B+ have fins for it.
So, for now, I'm using the same 3B that I have used for the past year. I'm expecting a new 3B+ to be delivered Thursday, along with a dual fan kit to fit over the top. I'll try it in the case and see how it does - If there is a problem I'll drill a few holes in the case next to the RPI.
Another thing I learned while I had the 3B+ working - power is really a problem! The little 3A buck converter I was using came out and I replaced it with a 10A unit. Also, all the power wires have been enlarged. I found that at the current that the 3B+ draws, there was as much as a 0.5V drop in the crappy USB cable I was using for testing. It was causing low voltage alarms in the syslog, which was slowing the processor down. I did find a way to solder dedicated power wires on the bottom of the RPI to avoid using the micro-USB connector completely. It seemed to help.
Otherwise, I'm very happy with the result. Now I'm trying to get an I2C display to work, but I can't find a functional Node-Red node for it. I guess it'll have to be Python or something!
However, one of the reasons I decided to tear this build down and do it again was because I wanted to put in a new 3B+. I had it working on the bench, not mounted, for several days. One day I came in to look at it and it was dead, red light was on but it wouldn't boot from anything. I don't know what happened, it could've just been the board getting laid down on a screw or something and it got shorted somehow, but I did notice the board got REALLY hot. I had cooling fins on the processor and the LAN chip, but didn't have anything for the WiFi shield (the one with the RPI logo on it). The WiFi shield got really hot as well. I did notice that some of the newer cooling kits for the 3B+ have fins for it.
So, for now, I'm using the same 3B that I have used for the past year. I'm expecting a new 3B+ to be delivered Thursday, along with a dual fan kit to fit over the top. I'll try it in the case and see how it does - If there is a problem I'll drill a few holes in the case next to the RPI.
Another thing I learned while I had the 3B+ working - power is really a problem! The little 3A buck converter I was using came out and I replaced it with a 10A unit. Also, all the power wires have been enlarged. I found that at the current that the 3B+ draws, there was as much as a 0.5V drop in the crappy USB cable I was using for testing. It was causing low voltage alarms in the syslog, which was slowing the processor down. I did find a way to solder dedicated power wires on the bottom of the RPI to avoid using the micro-USB connector completely. It seemed to help.
Otherwise, I'm very happy with the result. Now I'm trying to get an I2C display to work, but I can't find a functional Node-Red node for it. I guess it'll have to be Python or something!