FIELD OF THE INVENTION
The invention relates to a system for reading multiple digital inputs from a location and give out multiple digital outputs at a different location. More particularly, the invention relates to signal concentrator and distribution system through serial communication. The invention further relates to a signal concentrator and distribution system which avoids the bulk of signal cables by replacing it with serial communication. The invention also relates to a signal concentrator and distribution system for digital input-output for industrial as well as commercial applications. The invention also enables power supply isolation between input and output sides.
BACKGROUND OF THE INVENTION
Any industrial or commercial application in the present time has an element of automation. The same warrants some sort of an intelligent control system. One such control element is an input-output module. An input module receives an input signal from a switch or sensor. The signal from a sensor might be that a particular condition has been sensed, and some control step should now be taken. The input from a switch may be that the switch has switched from off to on, and some control action must be taken. The output module typically sends a signal to control an associated component based upon the signal from the switch or sensor or from a microcontroller.

Whether generating advanced patterns to characterize a custom circuit, toggling control lines to automate a factory floor or prototyping a digital design, many applications require some degree of digital input and output capability.
Presently, control signals typically of 24 Volt are used to control or drive digital outputs based on the input condition. Many cases the input/sensor and the actuator/output units are located far from each other and hence cables are run between them to establish signal transfer. As the number of input and output increases, the amount of cabling and associated cost, space, time requirement etc increases. Complex cabling will result in difficulty in commissioning of system as well as maintenance.
Industrial applications often involve requirements beyond the capabilities of a typical measurement device. For example, many industrial sensors and actuators require 24 V logic levels and may operate at different voltage potentials that can cause ground loops. Safety for the measurement or control system and safety for the user or operator are equally important.
The prior arts US20150278144A1 & US20160239007A1 describes a method of reducing wire connections by reading signals through communication lines. However, they need a PLC (Programmable Logic Controller) or SCADA (Supervisory Control And Data Acquisition System) in addition to the input and output units. They merely act as a data concentrator unit for giving data to PLC or SCADA. Also, the disclosure tells about a system where each individual sensor is connected to the data concentrator unit. This warrants the requirement for smart sensors with communication interface.

Other prior arts for eg. CN201965753U, KR101166329B1 are merely concentrating / acquiring data from different sensors. There is no inbuilt control mechanism. They mainly employ MODBUS RS485 or RTU and not any multimaster communication protocol. Absence of a multimaster communication network will add latency in communication as the network size grows.
OBJECTS OF THE INVENTION
It is therefore an object of the invention to propose a system of signal concentrator and distributor in serial communication protocol for routing signals from sensors and actuators from a first plurality to a second plurality of locations.
Another object of the invention is to propose a system of signal concentrator and distributor in serial communication protocol for routing signals from sensors and actuators from a first plurality to a second plurality of locations which eliminates the individual signal control cables that runs between the sensor and actuators and thereby reduces control/signal cables used in an industrial or commercial applications which inter alia avoids false switchings created due to inductance and capacitance of long run signal cables.
A still another object of the invention is to propose a system of signal concentrator and distributor in serial communication protocol for routing signals from sensors and actuators from a first plurality to a second plurality of locations which provides power supply isolation between the sensor/input side and the actuator/output side.

Yet another object of the invention is to propose a system of signal concentrator and distributor in serial multi-master communication protocol for routing signals from sensors and actuators from a first plurality to a second plurality of locations which reduces network delays/latency and enables multiple signal concentrator to multiple distributer connection.
A further object of the invention is to propose a system of signal concentrator and distributor in serial communication protocol for routing signals from sensors and actuators from a first plurality to a second plurality of locations which the micro-controllers and associated circuit processes the sensor input and then convert into communication data frames at the concentrator side and receive the converted frames at the distributer side and thereby process it to drive signal outputs for the actuator.
A still further object of the invention is to propose a system of signal concentrator and distributor in serial communication protocol for routing signals from sensors and actuators from a first plurality to a second plurality of locations which is provided with user settable address for unique identification and pairing between the data concentrator and data distributor.
SUMMARY OF THE INVENTION
Accordingly, there is provided a system of signal concentrator and distributor in serial communication protocol for routing signals from sensors and actuators from a first plurality to a second plurality of locations. The system is capable of

sensing the digital inputs from sensors or switches, converting the signals into serial communication frames, transporting the signals for processing the data packets, converting the processed signals into corresponding digital outputs to drive actuators or powering on devices.
The invented system has provision to read 24 numbers of digital inputs with optically isolated coupling to the microcontroller
The invented system has provision to give out 24 numbers of isolated digital outputs through relay potential free contacts driven by the microcontroller.
The invented system also has a multi master protocol based CAN (Controller Area Network) serial communication network for peer to peer communication to reduce network delays/latency associated with master-slave communication protocols and also enables multiple signal concentrator to multiple signal distributer connection.
The invented system also has hardware and the associated software, both at sensor/input side and actuator/output side, to read digital inputs and to convert it into CAN communication frame and send it through CAN communication bus, receive the frames, process it and give digital outputs
The invented system has provision to assign address to both the signal concentrator as well as the signal distributer units. Pairing between the two units is attained through matching address.

The hardware and the associated software is designed to have a one-to-one relation between the 24 digital inputs and the 24 digital outputs in the paired system.
The invented system completely eliminates the signal cables required individually for all input-output pair by means of the signal concentrator and distributer units connected through CAN through only a two wire communication bus.
The invented system provides power supply isolation between the sensor/input and the actuator/output side. We need not run the control power supply to route from input to the output side. Both sides can work in their own power supply.
The invented system avoids problems of false switching ON/OFF of actuators/outputs due to capacitance and inductance of long run control cables.
BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWINGS
Figure [1] is hardware block diagram of the proposed signal concentrator and distributer system for digital input-output application.
DETAILED DESCRIPTION OF A PREFERRED EMBODIMENT OF THE
INVENTION
In Figure [1], block (1) is the signal/input concentrator unit which can receive 24 numbers of digital input signals, convert it into CAN communication frame and send it to the signal/output distributer unit (2).

In Fig. 1, block (9) is a power supply unit for the signal/input concentrator which provides power for the microcontroller and peripheral devices. Similarly, block (15) is a power supply unit for the signal/output distributer which provides power for the microcontroller and peripheral devices.
■
In Figure [1], block (10) and block (14) are the address setting switch unit of signal concentrator (1) and distributer system (2) respectively. (10) assigns the physical address or identification for the respective units in the network. Signal concentrator (1) and distributer system (2) with the same address gets paired. That means the corresponding number input (6) of concentrator (1) matches with the corresponding number output channel (17) of the paired distributer system (2).
In Figure [1], block (5) represents the physical 2-wire CAN communication bus.
In Figure [1], block (8) and block (13) are the central microcontroller (dsPIC series) which executes the software methods for the functioning of signal concentrator (1) and distributer system (2) respectively. They have inbuilt memory to store the program (control logic). They have inbuilt CAN communication module for remote monitoring and control through a multi master communication network.
Block (8) has provisions to take digital signals as input signals. Block (13) has provisions to give out control signals as digital output signals.

In Figure [1], block (11) and block (12) are the CAN communication interfaces to block(l) and block (2) respectively. They connects the CAN bus between the modules for sending and receiving of CAN communication frames.
In Figure [1], (6) represents the 24 numbers of digital input signals coming from various sensors, switches etc into the input/signal concentrator (1) unit.
In Figure [1], block (7) represents the optical isolation module for interfacing the 24 numbers of input signals to the central microcontroller (8) unit of the input/signal concentrator (1).
In Figure [1], (17) represents the 24 numbers of digital output signals going out from the signal/output distributer (2) unit to drive various actuators/outputs etc.
In Figure [1], block (16) represents the relay potential free contacts driven by the microcontroller (13) for 24 numbers of isolated digital outputs from the signal/output distributer (2) unit.
In Figure [1], block (3) is one of the many modules exactly similar to block (1) except for a unique address connected in the CAN network. Similarly block (4) is one of the many modules exactly similar to block (2) but with an unique address connected in the CAN network.

WE CLAIM :
1. A system of signal concentrator and distributor in serial communication protocol for routing signals from sensors and actuators from a first plurality to a second plurality of locations comprising a signal concentrator unit capable of sensing 24 different digital inputs and a distributer unit capable of driving 24 different digital outputs, wherein both the signal concentrator and distributor unit is having microcontroller and associated software modules to process the digital signals and communication frames.
2. The system as claimed in claim 1, wherein the signal concentrator unit is provided with optical isolation for interfacing the digital inputs to the microcontroller unit.
3. The system as claimed in claim 1, wherein the signal distributer unit is provided with isolated digital outputs through relay potential free contacts driven by the microcontroller unit.
4. The system as claimed in claim 1, wherein both the signal concentrator and distributer units are connected to each other though wired CAN communication network and eliminating all the individual signal cables required for each input-output pair and reducing network latency.

5. The system as claimed in claim 1, wherein both the signal concentrator and distributer units are electrically isolated and power supply independence is attained between inputs and outputs.