Let's talk a bit about RB power voltage requirements.
I made some study about poe power handling inside routerboards in order to verify that they can be safely powered with meanwell AD-155B "24V" UPS power supply.
The AD-155B gives 28Vdc power output when it's adjusted to provide correct 27.2V end-charge to 24V battery (13.6V x 2).
So, I examined RB912-2HPND, RB750UP, RB750, SXT lite5.
RB912-2HPND is rated 30V max by Mikrotik, but it's LSP5523 power chip is rated 27V, so max safe voltage will be 27.5V (with poe diode drop voltage).
RB750UP is rated 30V max by Mikrotik, but it's LSP5502 power chip is rated 27V, so max safe voltage will be 27.5V (with poe diode drop voltage).
RB750 is rated 28V max by Mikrotik, but it's LSP5526 power chip is rated 23V, so max safe voltage will be 23.5V (with poe diode drop voltage).
SXT lite5 is rated 30V max by Mikrotik, but it's LSP5526 power chip is rated 23V, so max safe voltage will be 23.5V (with poe diode drop voltage)!!!
So, Mikrotik support, why are you over-rating poe requirements of your devices?
Do you think it's safe to play h24 @ 28Vdc an SXT lite5 which power chip is rated 23V and absolute maximum 25V ?
Give me some explanation about this.
Thanks