PLC Hardware

  

PLC Hardware

Chapter-4


  • A PLC is made up of both hardware and software. Hardware is the part of a system that you can see, and software is the collection of computer programs that control what the hardware does.

  • PLC hardware also connects to other hardware, such as input and output devices and human machine interfaces (HMl'S).

  •  Although not shown in the graphic, a programming device can be considered as PLC hardware, but it is only connected to the PLC when needed.

  • Because PLC applications vary in complexity, there is considerable variation in the appearance of PLC hardware.

  • In a typical application, small- and medium-sized PLC'S are often used to control individual machines or manufacturing cells.

  • These PLC'S typically communicate via a network to one or more larger PLC'S that collect data and coordinate the operation of some or all of the system.

  • Additionally, because the needs of customers vary widely.

Siemens SIMATIC PLC'S are available as

1. Modular controllers,

2. Embedded controllers, or as

3. PC-based controllers. Of these three categories, modular controllers are the most common.


Modular PLC'S


  • SIMATIC S7 Modular PLC'S include a variety of models.

  • For example, S7-300 and S7-400 PLC'S have been in service for many years.

S7-300 and S7-400 PLC'S


  • More recently, S7-1200 and S71500 have been introduced.


  • Regardless of the model, SIMATIC S7 modular PLC'S are optimized for control tasks and can be adapted to meet application requirements by adding modules. Typical PLC Module types are:

  1. CPU modules,

  2. power supply modules,

  3. signal modules,

  4. communication modules, and

  5. special purpose modules.


Central Processing Unit (CPU)


  • PLC CPU modules all contain: A microprocessor, which is an integrated circuit that runs the computer software and memory circuits that store the user program and related of data and may include a removable memory card.

  • A CPU may also have an internal power supply that converts the supplied power to the tittered, low- voltage DC needed by internal circuits.

  • If the CPU does not have an internal power supply, a system power supply module is needed to provide power CPU'S typically have the following three operating modes:




  • In the STOP mode, the CPU is not executing the user program, and a new program can be downloaded to the CPU.

  • In the STARTUP mode, the CPU executes any startup logic, if present.

  • In the RUN mode, the CPU executes the PLC scan repeatedly.

  • The specific mode the PLC is in at any given time depends on a software setting and whether or not a critical CPU error has occurred In the event of a critical error, the CPU is designed to go into the STOP mode.

  • The current mode for S7- 1200 and S7-1500 PLC'S is shown by the CPU RUN/STOP LED.

  • The current mode for S7-1500 PLC'S is also shown on the CPU's integrated display.




Chapter 5 we will discuss about Memory Types,CPU memory Organization ,Power Supply Module...


If you enjoyed this article, share it with your friends and colleagues!



Comments

Post a Comment

Popular posts from this blog

Danfoss VLT micro drive FC 51 Name Plate

Image
In this Article, we are going to discuss about what specifications are mentioned on the Danfoss VLT micro drive FC 51 name plate sticker. Welcome to controls and systems blog page, The nameplate sticker is located on the top of each VFD drives and shows the ratings, serial number, warnings catalog number, and other relevant data for each unit. This nameplate sticker is mostly the same in the VLT model VFD drives, with only a few changes in the some VLT model VFD drives. 1 st ROW: ( TYPE CODE ) Position 1 - 3 [FC]-  is Product group, Possible choice is: Frequency converters, Position 4 - 6 [051]  is Series and product type, Possible choice is: Micro Drive, Position 7 - 10  [P]  is Power size, Possible choice is: 0.18 to 22 kilo watt. Position 11 - 12  [S2]  is Mains voltage, Possible choice is: S2 that means Single phase 200 to 240 Volt AC, T2 that means 3-phase, 200 to 240 Volt AC, T4 that means 3-phase, 380 to 480 Volt AC, Position 13 - 15  [E20]  i
Read More »

QElectro Tech Software Overview

Image
  In This Article we are going to see QElectro Tech Software Overview... QElectro Tech QElectroTech QElectroTech is a free software to create electric diagrams. QElectroTech or QET in short is currently available in version 0.80. This Software is Very Effective and Very Useful for Electronic, Electrical, and Instrumentation Department Engineers. Compare to other Diagram Software’s ‘exe’ Setup file of QElectro Tech Software Size is Too Low. There are Lot of Electrical, Electronic and Instrumentation Symbols and elements are in this QElectro Tech software. The Software of Table of Contents is following of ( Basics , Interface , Preferences , Project , Folio , Element , Conductor , Schema , Drawing , Reports , Export and print , Annex etc..) QElectro Tech Documentation 1 QElectro Tech Documentation 2 The QElectro Tech Software contains many collections (Electrical , Logic , Hydraulic , Pneumatic and Energy symbols and Elements) also user can create they own symbols. Anyone can Access
Read More »

SIEMENS V20 VFD DRIVE MAIN PARAMETERS LIST

Image
   SIEMENS V20 VFD DRIVE MAIN PARAMETERS LIST This Parameter Setting is Suitable for (  Manual ON/OFF Mode , Auto Frequency Mode , Pot meter Varying Mode ) its Deepened on (0-10)v Dc signal. SIEMENS V20 VFD DRIVE MAIN PARAMETERS LIST   Parameter Setting Description P0003 1 Standard: Allows access into most frequently used parameters P0010 30 Factory setting P0970 1 Resets all parameters P0010 1 Quick commissioning P0100 0 Europe [kW], motor base frequency is 50 Hz P0301 22 Rated motor KW [KW] P0304 415 Rated motor voltage [V] P0305 35 Rated motor current [A] P0307 22 Rated motor power P0308 0.82 Rated motor cosĪ† P0310
Read More »

SIEMENS V20 VFD DRIVE FAULTS CODE LIST PART-1

Image
In this article  we are going to discuss about siemens v20 vfd drive fault Cause and Remedy for this  fault codes ( F1, F2 , F3 , F4 , F5 , F6 , F11 , F12 , F20 , F35 )   SIEMENS V20 DRIVE F1  -  FAULT:    Overcurrent CAUSE : Motor power (P0307) does not correspond to the inverter power (r0206). Motor lead short circuit Earth faults r0949 = 0: Hardware reported r0949 = 1: Software reported r0949 = 22: Hardware reported REMEDY : Check the following: Motor power (P0307) must correspond to inverter power (r0206). Cable length limits must not be exceeded. Motor cable and motor must have no short-circuits or earth faults. Motor parameters must match the motor in use. Value of stator resistance (P0350) must be  correct. Motor must not be obstructed or overloaded. Increase ramp-up time (P1120) Reduce starting boost level (P1312) F2  -  FAULT:  Overvoltage CAUSE : Main supply voltage too high Motor is in regenerative mode r0949 = 0: Hardware reported r0949 = 1 or 2: Software reported REMEDY
Read More »

Siemens RDF300, 340,600 Room Thermostat Parameter List Part-1 (Service Level)

Image
In This Article we are going to see Siemens RDF300, RDF340, RDF600 Room Thermostat Parameter List Part-1 Service Level. SIEMENS RDF300 Control Parameter Display 1. Operating mode selector / Protection. 2. Change fan operation 3. Adjust setpoint and control parameters Control Parameter Parameter List P01 Description :  Control Sequence Factory Setting :   2-pipe, single duct [0 to 3] 1 (Cooling only) 4-pipe, [2 to 4] 4 (Heating & Cooling) Setting Range : 0 = Heating only 1 = Cooling only 2 = Manual H or C 3 = Auto Changeover 4 = Heating & Cooling P02 Description :  Mode selection by user via operating mode button Factory Setting :  1 (Protection, Comfort) Setting Range : 1 =  Protection, Comfort 2 =  Protection, Comfort, Economy P04 Description :  Selection of  °C or °F Factory Setting :   °C  Setting Range :  °C or °F P05 Description :  Sensor Calibration Default Value :  0.0 K Setting Range :  -3 to +3 K P06 Description :  Standard Temperature display  Default Value :  0 (Room
Read More »