Schneider Electric INTERBUS Basic Network Interface Module, 890USE19600 Version 1.0 manual

		Glossary
	P
parameterize		To supply the required value for an attribute of a device at run-time.
PDM		power distribution module. A module that distributes either AC or DC field power to
		a cluster of I/O modules directly to its right on the island bus. A PDM delivers field
		power to the input modules and the output modules. It is important that all the I/O
		clustered directly to the right of a PDM be in the same voltage group—either
		24 VDC, 115 VAC, or 230 VAC.
PDO		process data object. In CAN-based networks, PDOs are transmitted as unconfirmed
		broadcast messages or sent from a producer device to a consumer device. The
		transmit PDO from the producer device has a specific identifier that corresponds to
		the receive PDO of the consumer devices.
PE		protective earth. A return line across the bus for fault currents generated at a sensor
		or actuator device in the control system.
peer-to-peer		In peer-to-peer communications, there is no master/slave or client/server
communications		relationship. Messages are exchanged between entities of comparable or
		equivalent levels of functionality, without having to go through a third party (like a
		master device).
PLC		programmable logic controller. The PLC is the brain of an industrial manufacturing
		process. It automates a process as opposed to relay control systems. PLCs are
		computers suited to survive the harsh conditions of the industrial environment.
preferred module		An I/O module that functions as an auto-addressable node on an Advantys STB
		island but is not in the same form factor as a standard Advantys STB I/O module and
		therefore does not fit in an I/O base. A preferred device connects to the island bus
		via an STB XBE 1000 EOS module and a length of STB XCA 100x bus extension
		cable. It can be extended to another preferred module or back into a standard island
		segment. If it is the last device on the island, it must be terminated with a 120 Ω
		terminator.
premium		An Advantys STB network interface module designed at a relatively high cost to
network		support high module densities, high transport data capacity (e.g., for web servers),
interface		and more diagnostics on the island bus.
prioritization		An optional feature on a standard NIM that allows you to selectively identify digital
		input modules to be scanned more frequently during a the NIM’s logic scan.

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