AND GATE
I:0/0 I:0/1 O:0/0
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They are not differnt to start with SLC is a range of processors offered by Allen Bradley in their Industrial processors portfolio. SLC makes the most cost effective solution for low cost and simple Automation needs, which will be eventual phased out by 2018. SLC processors do support DeviceNet, ControlNet for comms, Ladder and Structred Text for programming.
Data Highway: The proprietary data network used by Allen Bradley PLCs to communicate information to and from other PLCs on the network or to and from host computers attached to the network.
Control Net: A real-time, control-layer network providing high-speed transport of both time- critical IO data and messaging data, including upload/download of programming and configuration data and peer-to-peer messaging, on a single physical media link
Device Net: A low-cost communication link that connects industrial devices to a network. It is based on broadcast-oriented communication protocol – the Controller Area Network (CAN).
Ethernet: The standard for local communications networks developed jointly by Digital Equipment Corp., Xerox, and Intel. Ethernet baseband coaxial cable transmits data at speeds up to 10 megabits per second. Ethernet is used as the underlying transport vehicle by several upper-level protocols, including TCP/IP.
The commonly used communication protocol in AB includes DH+, DH485, ETH, Modbus, Device Net and Control Net.
The delay time between the end of one communication and the start of another. During this time, the processes associated with the communication are hung up and cannot continue. The latency has to be minimum.
The delay time between the end of one communication and the start of another. During this time, the processes associated with the communication are hung up and cannot continue. The latency has to be minimum.
A hardware assembly, which houses the processor, communication and I/O modules.
It does following functions.
Power distribution
Containment of I/O modules
Communication path between I/O module and CPU
The chassis are available in different slots in various PLC systems. Additional chassis can be connected using chassis interconnecting cable.
A hardware assembly, which houses the processor, communication and I/O modules.
It does following functions.
Power distribution
Containment of I/O modules
Communication path between I/O module and CPU
The chassis are available in different slots in various PLC systems. Additional chassis can be connected using chassis interconnecting cable.
Electronic plug in units used for interfacing the i/p and o/p device in the machine or process to be controlled.
I/P module receives data from i/p devices (Pushbutton, Switches, Transmitters) and send it to processor. The O/P module receives data from processor and send it to output device (Relay, Valves).
Digital/Discrete :- Sends and Receives On/Off signal
Analog :- Sends and receives variable input or output signals
Memory that is configured by the user to maintain values through a power cycle or a "program" to "run" transition.
