09-19-2022, 06:19 PM
Hi mathygreen, thanks for signing up and those are good questions.
I've tested various extensions with 50 feet of cable, that includes the AC power bars, sensor extension, equipment extension, 6 DC / 2 Sensor module and the 6 sensor / 2 DC module as long as those have their own power supply as you mentioned. No current is sent through these lines so voltage drop isn't to serious of a problem but it was starting to drop at 50 feet. With that said the sensor extension is powered through the RJ45 so current is supplied to power the sensors but they don't draw much either however I think AC power bars could be extended further due to this.
The two DB9 connectors and the sensor RJ45 on the main controller are a direct connection to the Pi GPIO's with no circuit. I did it like that to keep it as flexible as possible. Due to that if you took a 6 sensor / 2 DC extension you could connect only the ports you need to the output pins on the DB9's, that would leave you the extra GPIO's to do anything you want.
I haven't tried splitting a DB9 but I think that would work. For example if you ran a DB9 to a to a 6 sensor / 2 DC then split it and down the line added another 6 sensor / 2 DC they should both work in sync. That would allow you to use some ports in one location and the remaining in another without cutting up wires etc.
For the DS18B20 the results would basically be the same using 15 meter sensor vs extending the sensor extension. The DS18B20 is susceptible to noise so it might be better to extend the sensor module as the Ethernet cable is twisted which might help but I can't be sure. It's also possible to get shielded Ethernet cable which could help in noisy environments. If the DS18B20 cable runs along AC power cables it can be a problem especially if the AC device has a large motor, at that point you would want some shielding.
The sensor extension that plugs in the RJ45 can run DB18B20's however the 6 sensor / 2 DC and 2 Sensor / 6 DC extensions won't work with them so that's something to consider.
If you can draw out a simple diagram on what you want and distances I can be more sure but I don't think you'll have a problem.
I've tested various extensions with 50 feet of cable, that includes the AC power bars, sensor extension, equipment extension, 6 DC / 2 Sensor module and the 6 sensor / 2 DC module as long as those have their own power supply as you mentioned. No current is sent through these lines so voltage drop isn't to serious of a problem but it was starting to drop at 50 feet. With that said the sensor extension is powered through the RJ45 so current is supplied to power the sensors but they don't draw much either however I think AC power bars could be extended further due to this.
The two DB9 connectors and the sensor RJ45 on the main controller are a direct connection to the Pi GPIO's with no circuit. I did it like that to keep it as flexible as possible. Due to that if you took a 6 sensor / 2 DC extension you could connect only the ports you need to the output pins on the DB9's, that would leave you the extra GPIO's to do anything you want.
I haven't tried splitting a DB9 but I think that would work. For example if you ran a DB9 to a to a 6 sensor / 2 DC then split it and down the line added another 6 sensor / 2 DC they should both work in sync. That would allow you to use some ports in one location and the remaining in another without cutting up wires etc.
For the DS18B20 the results would basically be the same using 15 meter sensor vs extending the sensor extension. The DS18B20 is susceptible to noise so it might be better to extend the sensor module as the Ethernet cable is twisted which might help but I can't be sure. It's also possible to get shielded Ethernet cable which could help in noisy environments. If the DS18B20 cable runs along AC power cables it can be a problem especially if the AC device has a large motor, at that point you would want some shielding.
The sensor extension that plugs in the RJ45 can run DB18B20's however the 6 sensor / 2 DC and 2 Sensor / 6 DC extensions won't work with them so that's something to consider.
If you can draw out a simple diagram on what you want and distances I can be more sure but I don't think you'll have a problem.
