I had an immediate failure of a RUT241 powered from an external 24V when connecting the LAN port to a TSW202 (with the PoE for the port on this device turned off). The power for both of these devices share a common ground. Do these devices need to have isolated grounds in order to not have the TSW202 damage the RUT241?
hi, @jason.bendel
Before connect the rut241 to tsw202, you must read this:
- The device is NOT COMPLIANT with the IEEE 802.3af-2003 standard: powering the device from an IEEE 802.3af-2003 power supply will damage the device as it is not rated for input voltages of the PoE standard.
- The device is NOT COMPLIANT with the IEEE 802.3at standard: it cannot power other devices over Ethernet.
- The device is NOT COMPLIANT with the IEEE 802.3bt standard.
So…
Reading this url RUT241 Powering Options - Teltonika Networks Wiki you will find instructions about the ethernet cable to use/build for the RUT241.
Hello,
To clarify, isolated grounds are strictly unnecessary in this case. The TSW202 and RUT241 can safely share a common ground without issue, provided the PoE functionality is correctly managed (as you mentioned, PoE was turned off for that port).
For reference and to help ensure the setup is correct, you can find a useful example of how to connect passive PoE devices with the TSW202 on our wiki page below:
Disclaimer: If TSW202 and a Passive PoE device are connected with common ground, do not use LAN1 port , other ports can be used (refer to image below):
Additionally, could you clarify what was damaged? Can the RUT241 be powered using the default PSU (4-pin)?
Best regards,
Hi @Marcelo.Barros,
Thank-you for your input.
To clarify, the RUT241 was powered via the 4-pin connector with 24V. The connection between the devices was done from TSW202 port 3 (PoE turned off, but it looks like it must be switched on the low side), and the RUT241 only has one LAN port.
Based off of this information, we may either need to use a different RUT device with more ports, or potentially reconfigure the WAN port on the RUT241 to act as a LAN port.
As for what was damaged, it looks like the device just to the right of the 4 pin connector was damaged. I’m assuming it’s a diode. I don’t see any other physical signs of damage.
Hello @jason.bendel,
I just wanted to follow up on this and ask how you approached this “catastrophic failure” situation further. Did you proceed with an RMA, or is it still pending?
If not, could you please provide the batch number of the RUT241 device in question?
Looking forward to your reply.
Best regards,