What is a -48V power supply system?

Products basically use -48V power supply system, and the actual measured voltage is generally –53.5V. This is because for reliability reasons, communication equipment is equipped with a backup battery (-48V). In order to ensure reliable charging of the battery, the supply voltage needs to be slightly higher than the battery voltage.

What is the operating voltage range for -48V system equipment?

For -48V system equipment, the required operating voltage range is -38.4V ~ 57.6V, but in fact we generally require the operating range -36V ~ -72V. The main consideration is that -48V system equipment must be compatible with –60V power supply system, which requires –48~-72V.

Why is a –48 V DC a positive ground system?

The short story is that –48 V DC, also known as a positive-ground system, was selected because it provides enough power to support a telecom signal but is safer for the human body while doing telecom activities.

What is the output voltage of a power supply?

Generally, the output voltage of the power supply is measured to be 26.8V. Generally, the equipment is required to work normally within the voltage fluctuation range of ±20%. For -48V system equipment, the required operating voltage range is -38.4V ~ 57.6V, but in fact we generally require the operating range -36V ~ -72V.

What is a -48 volt DC power system?

Telecommunication networks consist of central offices or exchanges where switching and routing equipment is housed. -48 volt DC power systems offer excellent power efficiency, especially in large-scale deployments. DC power distribution is more efficient compared to AC power due to reduced energy losses during conversion and transmission.

What power supply is used in a central office communication system?

Later, in order to be compatible with early equipment and reduce costs, the central office communication equipment still used -48V power supply. Likewise, with a negative power system, the positive ground is just a convention. It turns out that there is a saying that there are a lot of negative charges in the air.