I made a circuit board that fits into the APC rack.  It is an Ethernet fuse 
board.   Kinda a belt and suspenders for maximum protection of an CAT5/6 
circuit.  If a surge suppressor clamps during a major event, this fuse board 
will blow to prevent damage to a POE supply.  Have LEDS on 4 of the 8 pins to 
detect blown fuses if it is a POE circuit.  

Been tweaking the fuse values for about a month.  Did the first run of the 
pre-production part and started testing.  I tweaked the fuses to blow about a 
bit over 2 amps.  

Started doing some long term burn in runs to check thermal considerations etc.  
Had the load dialed in to 2 amps.  Powered by a Netonics doing 54 volts.  

It ran for about a half hour before blowing the Netonix port.  They say 2 amps 
surge, 1.5 amps continuous.  I think they actually mean it.  I was hoping it 
would survive 2 amps continuous, but it will not.  So I have a roll of smt 
fuses that are worth about $650 that I will not be using unless I release a 1.5 
amp and a 2 amp version of this product.  

RJ45 pins are rated at a half amp each so 2 amps per jack.  2 amps would be a 
good generic value.  Not sure whether to offer two different amp ratings or 
one.  

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