- The Profiler Model referred to in this thread is ...
- ☑️ Profiler Head/Rack
If your Kemper Remote does no longer connect to your Profiler and you have definitely ruled out possible cable problems, and your Remote is outside the warranty period, then here is my advice:
Save yourself the hazzle and unneccessary cost for shipping the Remote (and your Profiler, as they always want you to send in both units) to the service.
They won't really repair your Remote, but simply replace all the PCBs (printed circuit board), which means almost everything except the metal case and they will charge you almost 300.- EUR for that, which is completely uneconomical (and not exactly sustainable either), considering that you "only" pay 419.- for a brand new Remote.
Of course there is a possibility, that the cause of the connection problem is located on the Profiler, but this can be easily checked by using an approptiate PoE Ethernet Switch. Connect that switch to your LAN and hook up the Profiler and the Remote to the Switch. Then check, if the Profiler connects to the Switch. If you get a link on the port, the Profiler is connected to and if you then can access the Profiler through the Rig Manager App on an Android Smartphone that is connected to your (W)LAN, you have proved, that the Ethernet interface of the Profiler basically works.
If your Remote powers up on the PoE switch but you don't even get a link on the Switch port it is connected to, then your Remote has a problem with its Ethernet interface (-> go and get a new remote). If you do get a link and the Remote now does connect to the Profiler, the cause of the problem can reside in the Profiler or in the Remote and is most likely related to the strange power supply concept that is used when the Remote is directly connected to the Profiler (however you do have a solution then, just use a PoE switch, which will also allow you to use longer cables).
For powering 10/100MBit PoE (Power over Ethernet) devices, there are basically two approaches: One (called Mode A) is to use the two Ethernet signal pairs that carry receive (RX, pair 1-2) and transmit (TX, pair 3-6) signals ALSO for delivering power to the Ethernet device. The other approach (called Mode B) is to directly use the cable pairs ( 4-5 and 7-8) which are unused for 100/100MBit Ethernet.
Unfortunately Kemper did not completely follow the corresponding IEE802.3af spec when designing Profiler and Remote and did something quite weird: While the Remote can be powered by a standard PoE switch that delivers power according to Mode A, it can't be powered by using Mode B, which is already a violation of the spec. But even worse: When you directly connect the remote to the profiler, the Profiler does NOT behave like a standard PoE Switch supporting mode A, as it does not deliver the power for the remote through the 1-2 and 3-6 signal pairs. The profiler uses the 4-5 and 7-8 cable pairs to power the remote, but in an out-of-spec way, as it only delivers 5V, while the nominal voltage would be 48V. There was a good reason for choosing that considerably high voltage, as it results in lower currents (the Ethernet interface was not designed to deliver power in the first place, hence cables and connectors are for signal transmission and not for conducting high currents) and is less sensitive to voltage drop along the cable. I really don't see the point in implementing a standardized interface (Ethernet with PoE) and then not following the corresponding specification.
The Profiler is such a great device, hence it is hard to understand why they decided to go for such bad engineering here (and unfortunately this does not only apply to Kempers PoE concept. The circuit design of the Remote itself also lets you raise your eyebrows on several places....).