英文關鍵字
accumulator
backup
battery
cable
center
commercial
communication
control
danger
dmitrov
electric
electricity
electronics
emergency
energy
enterprise
equipment
facility
illumination
indoor
industrial
industry
isolated
light
many
megafon
megaphone
motion
net
network
nobody
off
on
power
protect
protection
rack
reliability
room
row
safe
source
supply
switch
system
technology
tilt
transformer
turn
voltage