OVERVIEW

Basic Details: LYA010A Input/Output Module HITACHI

1 PLC Input/Output Modules

Introduction 1.1 Digital and Analogue Signals

Digital input/output signals are switching signals, a 1 or a 0.

Analogue signals, there are two kinds of voltage signals or current signals, generally signals transmitted by the transmitter, such as pressure transmitter to detect the pressure of the water pipe, will output a 4-20ma or 0-10V analogue signal to the PLC, the PLC for data processing.

Switching input point (DI), processing switching input signal.

Analogue input point (AI), processing analogue input signals (0-20 MADc, 0-5VDC).

Resistance signal (including RTD) input point, processing RTD or general resistance signal.

High-speed pulse input point, processing high-speed pulse signals.

Voltage (including thermocouple) input point, processing voltage input or thermocouple signals.

There are also communication functions for data exchange with the host computer or control subordinate controller instrument driver

1.2 Digital and analogue input modules

According to the different field input signals, the input module can be divided into switching input module and analogue input module.

The function of the switching input module is to convert various switching signals into TTL standard signals required by the CPU. Depending on the type of input power supply, they can also be DC input modules and AC input modules. The input signals are converted to TTL (5V) standard signals by photocoupling after voltage division, current limiting, and filtering.

The function of the analogue input module is to convert changing analogue signals such as temperature, flow, current, voltage, etc. into a number of digital signals which can be processed by the CPU. The analogue input circuit is generally composed of operational amplifier conversion, mode conversion (A/D), and optoelectronic isolation.

PLC input and output module types: digital input DI, digital output DO, analogue input AI, analogue output AO.

Digital inputs and outputs are generally 24V.

There are two types of analogue and four types of analogue. The two types are voltage type and current type. Voltage types are 0-10V and -10 to 10V. current types are mainly 4-20MA, 0-20MA. then the module converts the analogue to +32767~-32768 numbers through A/D conversion, and then implements the control.

The function of the signal template is to convert various process I/O signals. A variety of signal inputs are converted to digital quantities for easy recognition, processing and analysis by the PLC. Outputs are converted to analogue to a variety of regulatory mechanisms to perform, or the output is converted to a 2-bit do-it-yourself quantity to control a number of devices, such as start-stop, on and off

1.3 Digital Input/Output Module

The switching input module is a processing module that transfers external control www.ge-drive.com signals or field detection signals to the PLC CPU. External signals are generally buttons, proximity switches, travel switches, etc.

Output module is the PLC according to the input module input signals and internal logic programming logic for processing, processing results out of the switching output will be the output module of the high and low level signals, drive the external intermediate relays, contactors, indicators, solenoid valves and other components, so that the external equipment to carry out the corresponding action

1.4 Output module

The function of PLC output module is to amplify the power of the output signal.PLC signals are expressed in terms of level, in order to make them not distorted during being read, it needs to have a certain amount of reserve energy or a certain amount of signal power. The output module functions effectively as a power amplifier. The output module is the module that drives the external load.

Common PLC output devices, transistors, thyristors, relays.

PLC input modules are used to receive various parameters of the production process. (Start Stop)

PLC output module is used to send out the information obtained after the operation of the programmable controller and to complete the control of various industrial sites by realising the machine. (Execution results and output) 1. has good anti-interference ability.

2、It can meet the matching requirements of various signals in industrial site.