Low voltage has multiple meanings in the electric/electronic world. A common rule of thumb is that anything below 600 volts is considered low voltage. Factories that use automation can use multiple voltages. Dividing the electrical use into supply and controls aids in understanding the usage.
What causes poor quality power supply? ... Low voltage due to overloading on the network, loose connections, or too small a conductor wire carrying power to your house may cause dimming of your lights. In extreme cases, a loose connection can cause electric shocks from metal appliances and surfaces in your home
Anything with 50 volts or less is considered low voltage, and thus, wiring that is designed to carry less than 50 volts is considered low voltage wiring. It carries less power than what is typically found in the home – for example, most standard wall outlets are 120V or 240V