The Power Management Bus (PMBus) is an open standard power-management protocol. This flexible and highly versatile standard allows for communication between devices based on both analog and digital technologies, and provides true interoperability, which will reduce design complexity and shorten time to market for power system designers. Pioneered by leading power supply and semiconductor companies, this open power system standard is maintained and promoted by the PMBus Implementers Forum (PMBus-IF), a forum comprised of over 30 companies who have already adopted this standard.

The PMBus is essentially a gateway for users to have remote access to the power supply enabling them to monitor the unit’s vital signs including

The interface also allows users to adjust important parameters such as:

The interface also alarms the operator of possible issues with the unit, such as a variable operating outside of normal range or a malfunction with a fan or other system component. This is particularly valuable for horticulture applications that require regular adjustment of the light spectrum and light intensity.

DIGITAL COMMUNICATIONS PROTOCOL (I2C)

Digital communication is quickly taking over the power supply industry, with the I2C protocol becoming the most popular and widely accepted methods. The most important factor contributing to the success of I2C is the ease of integration. This is evident in the simple connection of I2C, which consists of two wires and a ground line.

PMBus compliant highlights that the communication method is I2C and that it is compliant to an industrially accepted format.
The primary benefit of PMBus and I2C is the fact that they are recognized as the industrially accepted format. This results in faster time to market, minimized documentation of software specifications, and better guidelines for the communication protocol.
Two other standard communication protocols are the RS232 and RS485. SL Power regularly develops custom power conversion solutions along with their partners and has the ability to incorporate any communication protocol necessitated by the customers spec.

RS232 – “RECOMMENDED STANDARD 232”

RS-232 is a standard communication protocol for linking computer and its peripheral devices to allow serial data exchange. In simple terms RS232 defines the voltage for the path used for data exchange between the devices. It specifies common voltage and signal level, common pin wire configuration and minimum, amount of control signals. As mentioned above this standard was designed with specification for electromechanically teletypewriter and modem system and did not define elements such as character encoding, framing of characters, error detection protocols etc. that are essential features when data transfer takes place between a computer and a printer. Without which it could not be adopted to transfer data between a computer and a printer. To overcome this problem a single integrated circuit called as UART known as universal asynchronous receiver/transmitter is used in conjunction with RS232.

RS485 (RECOMMENDED STANDARD 485)

RS-485, also known as TIA-485(-A), EIA-485, is a standard defining the electrical characteristics of drivers and receivers for use in serial communications systems. Electrical signaling is balanced, and multipoint systems are supported. The standard is jointly published by the Telecommunications Industry Association and Electronic Industries Alliance (TIA/EIA). Digital communications networks implementing the standard can be used effectively over long distances and in electrically noisy environments. Multiple receivers may be connected to such a network in a linear, multidrop bus. These characteristics make RS-485 useful in industrial control systems and similar applications.