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WiSP Swich WS-6-Mini
Cambium PMP 430 Power with 48V (0.75A) Special Cable to get pinout correct.
Power Source: TP-POE-HP-56G 2Amp power source using ethernet cross over cable to make power source match UBNT AirFiber PoE.

Issue: When I turn on the 48V (0.75A) PoE power on the port, I get log entries in the switch of "switch[777]: 48V is out of range (53.6V)". The PMP430 is powered up and accessible with no log errors. The length of cable from switch to PMP430 is about 2 meters (6 ft.)

How can I trouble shoot this error and resolve it so my log does not fill with these errors?

Brent

That is a range we had specified but it had been increased in newer firmware I thought, what version are you running?
Upgrade to v1.4.1 and see if the error goes away as I believe we increased the allowed voltage range without throwing an error.

Also the WS-6-MINI can accept any polarity on any pair for POE IN on port 1 so you do not need to a special cable to feed it power on port 1.

The reason for this is the WS-6-MINI uses a Bridge Rectifier to swap the polarity being fed into it around properly.

Which is why you can also power a WS-6 MINI with a MIMOSA POE BRICK.

So long as the polarity is balanced meaning (2) Pair Positive and (2) Pair Negative
ALWAYS FEED A WS-6-MIN WITH ALL 4 PAIR NOT JUST 2 PAIR AS YOU NEED ALL 8 WIRES TO HANDLE THE CURRENT

On a standard cable powering a WS-6-MINI:
Pair 1 Pins 1,2 so can be positive or negative
Pair 2 Pins 3,6 so can be positive or negative
Pair 3 Pins 4,5 so can be positive or negative
Pair 4 Pins 7,8 so can be positive or negative

You just can NOT mix pin polarity meaning that you could NOT put Positive on Pin 1 and Negative on Pin 2 because with POE only one polarity per pair is allowed which is why you have to be careful when crimping ends.

What I see under the Device -> Status page is that the Board 48V under power is steady at 53.6V with the PmP430 radio powered off. Once I power the PmP430 radio on, that 48V varies from 53.0 to 53.6. 53.0 is a green bar and 53.3 and up is a red bar. I think these alerts log each time the bar goes from a green to a red bar or from 53.0 to 53.3 or above.

Just some additional information I have observed.

brent.s wrote:What I see under the Device -> Status page is that the Board 48V under power is steady at 53.6V with the PmP430 radio powered off. Once I power the PmP430 radio on, that 48V varies from 53.0 to 53.6. 53.0 is a green bar and 53.3 and up is a red bar. I think these alerts log each time the bar goes from a green to a red bar or from 53.0 to 53.3 or above.

Just some additional information I have observed.

What ever voltage you feed the WS-6-MINI is the voltage it uses for the 48V POE option (note..if source of input power to mini is Port 1 , POE output voltage is minus 1.4 volts of input voltage, or minus 0.7 volts if power is input on rear panel barrel connector), so if you feed it 53V via Port 1 input POE power, 48V will read approximately 51.6V on the Device/Status Tab , understand?
The 48V is a pass through not a conditioned voltage, what comes in goes out.

We do condition the 24V as we have to reduce the input voltage 48V+/- to 24V
We also obviously condition the 3.3 volts

The voltage is fluctuating as you turn on POE as the voltage is being drawn down which is why you want to make sure you are powering the WS-6-MIN with ALL 4 pair not just a 2 pair POE source.

Think of wires as pipes, if your only feeding the WS-6-MINI then the amount of current or water has to flow through 2 pipes instead of 4 pipes so voltages will drop quicker.

Go read this http://www.calculator.net/voltage-drop-calculator.html

And then read up more about voltage drop on wire to understand more what your seeing.

I have updated to 1.4.1 and the log entries have stopped.

Thanks for this.

sirhc,
That power supply does power on all 4 pairs, and the only reason we are using it over the UBNT is that it will power up to 2A (this is in-case we need to ever power more devices which we may need at other sites). We thought the pinout order mattered and that was the only reason we used a crossover to make the power on the data pins match the UBNT AF.

You have been great help as always.

Gilbert