I have lots of old industrial devices and I want connect to those remotly via new KNOT Embedded LTE4 devices because tight spaces.
The KNOT has PoE 802.3af/at with 12-57V input and industrial devices uses 24VDC and I want power KNOT also with it. Because industrial device manufacture has decided not to use common connectors I need make make my own cables.
Industrial device has M12 connector for 10/100 ethernet (pinout below, non standard coded M12 connector).
So, my question is can I use following pins from RJ45 to power KNOT
Yes, that is somewhat cryptic in Mikrotik specs.
When they write:
PoE in802.3af/at
...
PoE in input Voltage18-57 V
They actually mean:
device is compatible with 802.3af/at (which per standard has ONLY a voltage range of 37-57 V for af and 42.5-57V for at)
device is also compatible with passive PoE (as low as 18 V) and in this case Mode B (4&5+ and 7&8 -) is used.
So, you can use the cable you sketched to connect the industrial device to a (100 Mb) PoE injector using Mode B.
You could probably get away with making a Y cable with pins 1,2,3,6 connected to pins 1,2,3,4 of your device and pins 4&5 and 7&8 connected to the power supply, but using a PoE injector is (IMHO) much cleaner, your conversion cable is "data" only and power supply is added through the injector.
I was thinking it must support it, but on specs it doesn't say it…
Yeah, PoE injector would be better ready made solution but it's tight space to try fit KNOT and injector
Anyway, I need to make own cable and power rails are nearby I think just separate those power cables...
But I would anyway make an Y adapter with a power jack female or a similar connector, so that you can easily connect/disconnect power, and keep the "conversion cable" as "data only".
I need make make my own cables.
