I have this board:

system resource print
uptime: 7m11s
version: 6.24
build-time: Dec/23/2014 13:38:45
free-memory: 110.0MiB
total-memory: 128.0MiB
cpu: MIPS 74Kc V4.12
cpu-count: 1
cpu-frequency: 750MHz
cpu-load: 1%
free-hdd-space: 110.8MiB
total-hdd-space: 128.0MiB
write-sect-since-reboot: 76
write-sect-total: 37229
bad-blocks: 0%
architecture-name: mipsbe
board-name: CRS109-8G-1S-2HnD
platform: MikroTik


and have 48V as a source power to jack ..

but system health don't show voltage correctly ..

system health print
voltage: 16.3V
temperature: 23C


why?