Under Construction

 

Theory -121 :- Root Cause Analysis

 

INTRODUCTION                            

           Root cause analysis (RCA) is a method of problem solving used for identifying the root causes of faults or problems.[1] A factor is considered a root cause if removal thereof from the problem‐fault‐sequence prevents the final undesirable event from recurring; whereas a causal factor is one that affects an event's outcome, but is not a root cause. Though removing a causal factor can benefit an outcome, it does not prevent its recurrence within certainty.

For example,

imagine an investigation into a machine that stopped because it overloaded and the fuse blew.[2] Investigation shows that the machine overloaded because it had a bearing that wasn't being sufficiently lubricated. The investigation proceeds further and finds that the automatic lubrication mechanism had a pump which was not pumping sufficiently, hence the lack of lubrication. Investigation of the pump shows that it has a worn shaft. Investigation of why the shaft was worn discovers that there isn't an adequate mechanism to prevent metal scrap getting into the pump. This enabled scrap to get into the pump, and damage it. The root cause of the problem is therefore that metal scrap can contaminate the lubrication system. Fixing this problem ought to prevent the whole sequence of events recurring. Compare this with an investigation that does not find the root cause: replacing the fuse, the bearing, or the lubrication pump will probably allow the machine to go back into operation for a while. But there is a risk that the problem will simply recur, until the root cause is dealt with.

General principles of root cause analysis

1. The primary aim of root cause analysis is: to identify the factors that resulted in the nature, the magnitude, the location, and the timing of the harmful outcomes (consequences) of one or more past events; to determine what behaviors, actions, inactions, or conditions need to be changed; to prevent recurrence of similar harmful outcomes; and to identify lessons that may promote the achievement of better consequences. ("Success" is defined as the near‐certain prevention of recurrence.)
2. To be effective, root cause analysis must be performed systematically, usually as part of an investigation, with conclusions and root causes that are identified backed up by documented evidence. A team effort is typically required.
3. There may be more than one root cause for an event or a problem, wherefore the difficult part is demonstrating the persistence and sustaining the effort required to determine them.
4.  The purpose of identifying all solutions to a problem is to prevent recurrence at lowest cost in the simplest way. If there are alternatives that are equally effective, then the simplest or lowest cost approach is preferred.
5. The root causes identified will depend on the way in which the problem or event is defined. Effective problem statements and event descriptions (as failures, for example) are helpful and usually required to ensure the execution of appropriate analyses.
6. One logical way to trace down root causes is by utilizing hierarchical clustering data‐mining solutions (such as GT data mining). A root cause is defined in that context as "the conditions that enable one or more causes". Root causes can be deductively sorted out from upper groups of which the groups include a specific cause. 154
7. To be effective, the analysis should establish a sequence of events or timeline for understanding the relationships between contributory (causal) factors, root cause(s) and the defined problem or event to be prevented.

Limitations of Root Cause Analysis

RCA is one of the most widely used methods to improving patient safety, but few data exist that uphold its effectiveness. The quality of RCA varies across facilities, and its effectiveness in lowering risk or improving medical safety has not been systematically established. The quality of RCA is dependent on the accuracy of the input data as well as the capability of the RCA team to appropriately use these data to create an action plan. In some cases, only one source of error or a few sources of error are emphasized, when in reality the situation might be more complex. The thoughts, conversations, and relationships of members play an important role in determining the effectiveness of an RCA team People tend to select and interpret data to support their prior opinions. An atmosphere of trust, openness, and honesty is critical to encourage members to share what they know without fear of being criticized or unacknowledged.

General process for performing and documenting an RCA‐based Corrective Action

1. Define the problem or describe the event to prevent in the future. Include the qualitative and quantitative attributes (properties) of the undesirable outcomes. Usually this includes specifying the natures, the magnitudes, the locations, and the timing of events. In some cases, "lowering the risks of reoccurrences" may be a reasonable target. For example, "lowering the risks" of future automobile accidents is certainly a more economically attainable goal than "preventing all" future automobile accidents.
2. Gather data and evidence, classifying it along a timeline of events to the final failure or crisis. For every behavior, condition, action and inaction, specify in the "timeline" what should have been done when it differs from what was done.
3.  In data mining Hierarchical Clustering models, use the clustering groups instead of classifying: (a) peak the groups that exhibit the specific cause; (b) find their upper‐groups; (c) find group characteristics that are consistent; (d) check with experts and validate.
4.  Ask "why" and identify the causes associated with each sequential step towards the defined problem or event. "Why" is taken to mean "What were the factors that directly resulted in the effect?"
5. Classify causes into two categories: causal factors that relate to an event in the sequence; and root causes that interrupted that step of the sequence chain when eliminated.
6. Identify all other harmful factors that have equal or better claim to be called "root causes." If there are multiple root causes, which is often the case, reveal those clearly for later optimum selection.
7.  Identify corrective action(s) that will, with certainty, prevent recurrence of each harmful effect and related outcomes or factors. Check that each corrective action would, if pre‐implemented before the event, have reduced or prevented specific harmful effects.
8.  Identify solutions that, when effective and with consensus agreement of the group: prevent recurrence with reasonable certainty; are within the institution's control; meet its goals and objectives; and do not cause or introduce other new, unforeseen problems

Theory - 120 :- Service Management Concept

Service Management Concept

INTRODUCTION                

Service management in the manufacturing context, is integrated into supply chain management as the intersection between the actual sales and the customer. The aim of high performance service management is to optimize the service‐intensive supply chains, which are usually more complex than the typical finished‐goods supply chain. Most service‐intensive supply chains require larger inventories and tighter integration with field service and third parties. They also must accommodate inconsistent and uncertain demand by establishing more advanced information and product flows. Moreover, all processes must be coordinated across numerous service locations with large numbers of parts and multiple levels in the supply chain.

Among typical manufacturers, post‐sale services (maintenance, repair and parts) account for less than 20 percent of revenue. But among the most innovative companies in service, those same activities often generate more than 50 percent of the profits.

Benefits

• The main drivers for a company to establish or optimize its service management practices are varied:
• High service costs can be reduced, i.e. by integrating the service and products supply chain.
• Inventory levels of service parts can be reduced and therefore reduce total inventory costs.
• Customer service or parts/service quality can be optimized.
• Increasing service revenue
• Reduce obsolescence costs of service parts through improved forecasting.
• Improve customer satisfaction levels.
• Reduce expediting costs ‐ with optimized service parts inventory, there is no need to rush orders to customers.
• Minimize technician visits ‐ if they have the right part in hand, they can fix the problem on the first visit.

• Service strategy and service offerings

•  Service strategy definition

•  Service offerings definition & positioning 
• Go‐to‐market strategy
•  Service portfolio management

• Spare parts management
• Parts supply management
• Inventory management
• Parts demand management
• Fulfillment operations & logistics
• Service parts management

• Returns, repairs, and warranties
• Warranty & claims management  
• Reverse logistics
• Returns processing
• Remanufacturing

• Field service management or field force effectiveness
• Technician enablement
• Mobility
• E‐learning
• Activity scheduling
• Service billing

• Customer management
• Order management & availability  
• Channel & partner management
• Customer insight
• Technical documentation

• Assets, maintenance, task scheduling, event management
• Remote monitoring
• Diagnostics & testing
• Asset management/optimization
• Configuration management

Theory :- 116 :- Form Factor Of Mother Board

Form factor of mother board

Motherboard Form Factors

MicroATX

 The microATX form factor was developed as a natural evolution of the ATX form factor to address new market trends and PC technologies. While offering the same benefits of the ATX form factor specification, the microATX form factor improves upon the previous specification in several key areas. Current trends in the industry indicate that users require a lower‐cost solution for their PC needs. Without sacrificing the benefits of ATX, this form factor addresses the cost requirement by reducing the size of the motherboard. The smaller motherboard is made possible by reducing the number of I/O slots supported on the board. The overall effect of these size changes reduces the costs associated with the entire system design. The expected effect of these reductions is to lower the total system cost to the end user.

<p

Through careful designing of a microATX motherboard, an OEM can capitalize on the benefits of a reduction in total system costs. These cost savings come from a reduced‐output power supply (see the separate document SFX Power Supply Design Guide), reduced chassis costs, and minimal redesign of existing ATX compliant chassis for backward‐compatibility.

<p

microATX benefits also include those found with the current ATX form factor: more I/O space at the rear and reduced emissions from using integrated I/O connectors.

.</p>

 FlexATX

 FlexATX offers the opportunity for system developers to create many new personal  computer designs.

.

BTX               

Balanced Technology Extended (BTX) Form Factor

The BTX form factor specification gives developers options to balance thermal management, acoustics, system performance, and size in the system form factors and stylish designs that are desired in today's products. The BTX form factor is a clear break from previous ATX form factor layouts and was developed with emerging technologies such as Serial ATA, USB 2.0, and PCI Express*.

Thermal improvements come primarily from taking advantage of in‐line airflow. The BTX defined in‐line airflow layout allows many of the main board components (i.e.: processor, chipset, and graphics controller) to utilize the same primary fan airflow, thereby reducing the need for, and 136 noise from, additional system fans. In some cases this also allows fewer and/or less expensive heat sinks to be used when compared to ATX solutions. The system level acoustics are also improved by the reduced air turbulence within the in‐line airflow system. The BTX layout supports better component placement for back panel I/O controllers – important as the signal speed of external devices continues to increase. In addition to smaller than microATX system sizes, BTX was designed to scale up to tower size systems using the same core layout by increasing the number of system slots included.

PRACTICAL -125 :- Replacing/upgrading Processor

હેતુ.: Replacing/upgrading Processor

તાલીમ માટે જરૂરી  સાધનો /  computer  system .

કાચો માલ સામાન :- Power Supply 230 volts .

As we have seen RAM module replace them and upgrade them  yet now discuss on Processor module for speed propose

નિર્દશન દરમીયાન  અનુસરવાનાં ક્રમીક પદો

• Turn off your PC and remove the power cable 
• Unscrew your computer's case and remove the cover. 
• Identify your motherboard, your current processor chip, your RAM memory cards, and your video card

• Find out what kind socket your motherboard has 
• If your current motherboard does support the new processor you want, buy the new processor at a computer hardware store of your choice and skip to   
• Socket 370: Intel Pentium III, Celeron 
• Socket 462 (socket A): AMD Athlon, Duron, Athlon XP, Athlon XP‐M, Athlon MP,

• Choose a motherboard that satisfies your criteria (which may depend on cost, technical specifications, or compatibility with your old hardware) 
• If compatibility exists with all the old hardware, jump to Part 3. 
• Investigate the compatibility of your video card and RAM memory

અમલીકરણ ( માર્ગદર્શન હેઠળ તાલીમાર્થીઓની પ્રવૃતી)

Open cabinet given system and identify processor  module replace them

કસોટી  ( તાલીમાર્થીઓની સ્વતંઞ પ્રવુતી)

Write down functionality of processor  module  

SEM -I , DAYWISE

 

SEM -1 QUE 1-25

 

SEM-1Q-1-22

 

SEM-I MCQ 1-20

 

ICTSM NSQF - Module 5 : Diode, Rectifier, Filter, Zener diode, Transistor and Amplifiers

 1. What is the current through the Zener diode with full load condition?

• Zero 
• Minimum 
• Maximum 
• Remains constant

 2. Which component filter the ripples in the rectifier circuit?

• DIAC 
• Diode 
• TRIAC 
• Capacitor

 3. Which parameter is maintained constant in Zener diode?

• Power
• Current 
• Voltage 
• Resistance

 4. When does the Zener diode begins to conduct in the reverse biased condition?

• When bias voltage reached 0.7 V 
• After the barrier voltage cancelled 
• Voltage across Zener reached 0.3 V
• Voltage across it reached the Zener voltage 

 5. What is the current through the zener diode under no load condition?

• Zero 
• Minimum 
• Maximum 
• Remains constant

 6. Which is used for to operate in the reverse breakdown region?

• Diode 
• Capacitor 
• Zener diode 
• Resistor 

 7. What is the meaning of first letter indicated in the transistor code number BC 107?

• Germanium material used 
• Silicon material used
• Antimony material used 
• Indium material used

 8. Which electrical quantity controls the operation of the bipolar transistor device?

• Energy 
• Current 
• Voltage 
• Frequency

 9. Why transistors made of silicon is preferred over the germanium semiconductor material?

• Complex design 
• Higher thermal stability 
• Requires complicated bias arrangement 
• Silicon transistor needs low cut-in-voltage.

10. Why NPN type of transistors are preferred over the PNP type transistors?

•  NPN has lower switching speed 
•  NPN has good bias stability 
•  NPN has higher switching speed 
•  Low operating voltage

 11. Which type of transistors are required to amplify signals from the microphone / transducer?

• Low power transistors
• Medium power transistors 
•  High power transistors 
•  Epitaxial versa watt transistors

 12. What type of packaging is generally used to transistors utilized for low power amplification?

• Metal packaging 
• Plastic packaging 
• Ceramic packaging 
• Plastic packaging with metal heat sinks

13. What is the voltage gain in a transistor if the input voltage in 40 mv and the output voltage in 3.6 V?

• 45 
• 90 
• 180 
• 270 

 14. How the negative feedback is called?

• Regenerative feedback 
• Degenerative feedback 
• Current controlled feedback
• Voltage controlled feedback

 15. What is the advantage of using bias in transistor circuits?

• Provides positive feedback 
• Never reach saturation 
• Easily sets saturated 
• Gives maximum distortion

MCQ PRACTICE - SEM -I MODULE - I

 1. What is the meaning of maximum safe reverse voltage across a diode?

• PIV voltage 
• Knee voltage 
• Break down voltage 
• Reverse break down voltage 

> 2. What is the peak inverse voltage of germanium diode?

• 0.3 V
• 0.7 V
• 0.8 V
• 1 V

3. Which is the first step followed in troubleshooting of electronic circuit? 

• Thermal test 
• Chemical test
• Mechanical test 
• Physical and Sensory test

4. Which diode is used in low power communication circuits?

• Signal diodes
• Rectifier diodes 
• Switching diodes 
• High power diodes

5. What is the process of adding impurities to a pure semiconductor material?

• Doping
• Etching 
• Forming
• Diffusion 

6. Which impurity is added to form P - type semiconductor material? 

• Arsenic
• Gallium 
• Antimony
• Phosphorus

7. Which impurity is added to pure semiconductor to form ‘N-type’ material?

• Boron 
• Indium 
• Arsenic 
• Gallium

8. What is the name of the process of converting AC into DC voltage?

• Inverting 
• Rectifying 
• Amplifying 
• Demodulating 

9. What is the name of the circuit diagram?

• Bridge rectifier 
• Amplifier circuit
• Regulator circuit
• Modulator circuit

10 What is the output pulse frequency of the full wave rectifier with input frequency of 50 Hz?

• 40 Hz 
• 60 Hz
• 100 Hz 
• 200 Hz

11. What is the disadvantage of the two diode full wave rectifier compared with a bridge rectifier?

• DC output level is higher 
• The ripple frequency is higher
• The need of Centre tapped transformer
• Each diode carries half the load current

12. What is the output frequency of the pulse setting DC in a two diode fullwave rectifier?

• Half of the input A/C frequency 
• Double the input A/C frequency 
• Same frequency of the A/C input 
• Three times the input A/C frequency

13.Which active components is used for AC to DC converter in rectifier circuit?

• Transformer 
• Diode 
• Capacitor 
• Resistor

14. Which rectifier circuit used for four diodes?

• Full  wave 
• Half  wave 
• Bridge 
• Two half wave 

15. What type of ripple filter circuit is used for large load current requirements?

• LC filter 
• RC filter Inductor I
• Input filter 
• Capacitor Input filter

પ્રશ્ન નવી CBT EXAM પધ્ધતિ માં શુ છે ?

    

 પ્રશ્ન 1  નવી CBT EXAM પધ્ધતિ માં શુ છે ? 

👉 *પેપર: 1 ( બધાજ વિષયો)  

👉 સમય: 2 કલાક

👉 કુલ પ્રશ્નોની સંખ્યા: 75

👉 કુલ માર્કસ:* 150

 પ્રશ્ન 2 એન્જીનીયરીંગ ટ્રેંડમાં વિષય મુજબ પ્રશ્નો અને માર્કીંગ સ્કીમ કઇ રીતે રહેશે? 

👉    ટ્રેડ થીયરી:                                 38 પ્રશ્નો,         76 માર્કસ 

        વર્કશોપ કેલકયુલેશન સાયન્સ:      6 પ્રશ્નો,           12 માર્કસ 

         એન્જીનિયરીંગ ડ્રોઇંગ:                 6પ્રશ્નો,             12 માર્કસ 

         એમ્પલોયેબિલિટી સ્કિલ્સ:         25 પ્રશ્નો,            50 માર્કસ

 પ્રશ્ન 3 પાસ થવા કેટલા માર્ક્સ લાવવાના ? 

👉ટ્રેડ થિયરીમાં પાસ થવા 40 ટકા માર્ક્સ એટલે કે કુલ 50 માંથી 20 પ્રશ્નોના જવાબ સાચા પડવા જ જોઈએ.

 પ્રશ્ન 4 ડ્રોઈંગ અને વર્ક.કેલ.સાયન્સ માં કેટલા લાવવાના ?

👉વર્કશોપ કેલ. સાયન્સ અને એન્જી.ડ્રોઈંગ માં અલગથી પાસ થવું જરૂરી નથી. 40 ટકા માર્ક્સ એટલે કે ટ્રેડ થિયારીના કુલ 50 પ્રશ્નોમાંથી બધા થઈને કુલ 100 માર્કસમાંથી માંથી 40 માર્ક્સ લાવો એટલે પાસ.

 પ્રશ્ન 5 ઇએસ માં અલગથી પાસ થવું પડશે ? 

👉હા...ઇએસ પાસ થવા માટે 40 ટકા માર્ક્સ એટલે કે કુલ 25 માંથી 10 પ્રશ્નો ના જવાબ સાચા પડવા જ જોઈએ.

🚨 ઇ એસમાં અલગથી પાસ થવું પડશે . કુલ 150 માર્ક્સ માંથી 40 ટકા માર્ક્સ આવ્યા એટલે ઇએસમાં  પાસ એવું નથી .

 પ્રશ્ન 6 * નોન એન્જીનીયરીંગ ટ્રેંડ જેમા વર્કશોપ કેલકયુલેશન અને સાયન્સ અને એન્જીનીયરીંગ ડ્રોઈંગ  નથી આવતું ઉદાહરણ તરીકે કોપા,HSIએમની પરીક્ષા પદ્ધતિ કેવી રહેશે ?* 

👉    ટ્રેડ થીયરી:                            50 પ્રશ્નો,     100 માર્કસ

         એમ્પલોયેબિલિટી સ્કિલ્સ:     25 પ્રશ્નો,      50 માર્કસ

 પ્રશ્ન 7પરીક્ષા કઇ ભાષામાં આવશે* ?* 

👉ત્રણ ભાષામાં પેપર આવશે.

        ગુજરાતી, હિન્દી, અંગ્રેજી

👉એક જ વખત ભાષા સિલેક્ટ કરવા મળશે. 

👉જે સિલેકટ કરો એ વિચારીને કરવું.પછી ચેન્જ નથી થતું.

👉દર વખતે સોફ્ટવેર અપડેટ થાય છે એટલે એવી શક્યતા ખરી કે આ વખતે ચાલુ પરીક્ષા એ ભાષા ચેન્જ કરવા મળે કે પછી પ્રશ્ન એકથી વધુ ભાષામાં ડિસ્પ્લે થાય..

🪴 પણ આ શક્યતા છે માટે તમામ તાલીમાર્થીઓને એક જ વખત ભાષા સિલેક્ટ થશે એજ રીતે જ માનસિક રીતે તૈયાર રહેવું.

Theory - 115 :- Function of mother board

Function of mother board

Introduction The motherboard is a sheet of plastic that holds all the circuitry to connect the various components of a computer system. Learn how the motherboard functions to make all the other components work together.

Definition               

 A motherboard is one of the most essential parts of a computer system. It holds together many of the crucial components of a computer, including the central processing unit (CPU), memory and connectors for input and output devices. The base of a motherboard consists of a very firm sheet of non‐conductive material, typically some sort of rigid plastic. Thin layers of copper or aluminum foil, referred to as traces, are printed onto this sheet. These traces are very narrow and form the circuits between the various components. In addition to circuits, a motherboard contains a number of sockets and slots to connect the other components.

Major Motherboard Components

• CPU (Central Processing Unit) chip
• RAM (Random Access Memory) slots
• Southbridge/northbridge
• BIOS (Basic Input/Output System)
• I/O port
• USB (Universal Serial Bus)
• CPU slot
• PCI (Peripheral Component Interconnect) slot
• AGP (Accelerated Graphics Port) slot
• ISA (Industry Standard Architecture) slot
• Parallel port
• FDC (Floppy-Disk Controller)
• IDE (Integrated Drive Electronics) controller
• CMOS (Complementary Metal-oxide-semiconductor) battery
• Power supply connector
• Mouse and keyboard ports
• DIP (Dual In-line Package) switch
• Jumper
• Heat sink/heatsink (cooling system)
• Clock generator

• CPU (Central Processing Unit) chip                                                                  CPU is the electronic circuitry in a computer that executes instructions that make up a program. It is also known as a central processor or the main processor. The CPU executes the basic logic, arithmetic, controlling as well as input/output (I/O) operations specified by the instructions in the desktop programs. 

• RAM (Random Access Memory) slots                                                                      RAM is a kind of computer memory that can be read and written. It is mainly used to save data and machine code. A RAM device permits data to be read or written in nearly the same amount of time no matter where the data’s physical location is in the memory. Compared to the direct-access storage devices like hard drives, CD/DVD and magnetic tapes, RAM media is much faster for data reading and writing.

• Southbridge/ north bridge

They are the two chips in the core logic chipset on the motherboard. Typically, the southbridge implements the slower capabilities of the motherboard in a northbridge/southbridge chipset computer architecture.

• The northbridge, also known as host bridge or Memory Controller Hub, is connected directly to the CPU via the front-side bus (FSB). It is responsible for tasks requiring the highest performance. Together with the southbridge, they manage communications between the CPU and other motherboard components.

• BIOS (Basic Input / Output System)

BIOS, also called system BIOS, PC BIOS or ROM BIOS, is firmware that is used to perform hardware initialization during the booting process; and to provide runtime services for operating system and programs. The BIOS firmware is the first software to run when powered on; it is re-installed on a PC’s system board.

• I/O port

Input/output ports are the connections between the CPU and peripheral devices on a motherboard. There are two complementary methods to perform input and output processes: memory-mapped I/O (MMIO) and port-mapped I/O (PMIO). Alternatively, you can use dedicated I/O processors, called channels on mainframe computers, which execute their own instructions. 

• USB (Universal Serial Bus)

USB is an industry standard that creates specifications for connectors, cables and protocols for connection; power supply (interfacing) and communication among computers, computer peripherals as well as other desktops. There are a great many USB hardware including several different connectors, of which USB-C is the latest kind.  

• CPU slot

A CPU slot, also called a CPU socket or Processor socket, contains one or more mechanical components that provide mechanical and electrical connections between the PCB and a microprocessor (CPU). Therefore, you can install a CPU on a motherboard without soldering.

• PCI (Peripheral Component Interconnect) slot

Peripheral Component Interconnect is a local computer bus for connecting hardware to a computer. It supports all the functions of a processor bus. PCI is usually been called Conventional PCI to distinguish it from its successor PCI Express (PCIe, PCI-e or PCI-E).

• PCI Express is a high-speed serial computer expansion bus standard designed to replace the older PCI, PCI-X and AGP bus standard. It is a general-use motherboard interface for the graphics card, SSDs, hard drives, Wi-Fi as well as Ethernet hardware connections.

•  AGP (Accelerated Graphics Port) slot

AGP was designed as a high-speed point-to-point channel for connecting a video card (graphics card) to a computer system. Primarily, it was used to assist in the acceleration of 3D computer graphics. AGP is originally designed to be a descendant of the PCI series of connections for video cards. Yet, it was replaced by the PCIe slots.

• ISA (Industry Standard Architecture) slot

ISA is the 16-bit internal bus of IMB PC/AT and similar computers that are based on Intel 80286 and its immediate successors during the 1980s. It was backward compatible with the 8-bit bus of the 8088-based IBM PC largely.

• There once was an attempt to extend ISA into a 32-bit bus, called Extended Industry Standard Architecture (EISA). The attempt wasn’t very successful and the EISA was largely replaced by the later VESA Local Bus and the PCI bus.

• Parallel port

A parallel port is a kind of interface for attaching peripherals on desktops. The name of this kind of port is derived from the way the data is sent. That is, the parallel ports send multiple bits of data at the same time. Serial interfaces, on the contrary, send bits one data at once. To achieve parallel data transfer, there are multiple data lines in the parallel port cables. The parallel port cable is larger than the cable of a contemporary serial port, which only has one data line within. 

• FDC (Floppy-Disk Controller)

FDC is a special-purpose chip and associated disk controller circuitry. It controls and directs reading from and writing to a computer’s floppy disk drive (FDD).

 

• IDE (Integrated Drive Electronics) controller

The devices used for connecting IDE, Ethernet, FireWire, USB and other systems can be called host adapter. So, the IDE controller refers to the host adapter. A host adapter, also called a host controller or a host bus adapter (HBA), connects a computer (acting as the host system) to other network and storage devices.

• CMOS (Complementary Metal-oxide-semiconductor) battery

CMOS battery, also called memory battery, clock battery or real-time clock (RTC), is generally a CR2032 lithium coin cell. The lifespan of the CMOS battery is estimated to be three years when the power supply unit (PSU) is unplugged or switch off.  

• Power supply connector

A power supply provides the necessary electrical power to let the computer to work. It takes standard 110-Volt AC (Alternative Current) power to DC (Direct Current) power of 12 Volt, 5 Volt, 3.3 Volt, etc.

• Mouse and keyboard ports

All computers have a keyboard port connected directly to the motherboard. There are two types of connectors. The oldest one is a special DIN (Deutsches Institut für Normung) connector while the newest one is the mini DIN PS/2-style connector. Many PCs use the PS/2-style connectors for both keyboard and mouse; and the connectors are marked clearly for different usage.  

• DIP (Dual In-line Package) switch

A DIP switch is a manual electric switch packaged with others in a standard dual in-line package. The term may refer to an individual switch or the whole unit. The DIP switch is designed to be used on a printed circuit board (motherboard) together with other electronic motherboard components. It is usually used to customize the behavior of an electronic device for specific situations.

• Jumper

A jumper is a short length of conductor that is used to close, open or bypass part of an electronic circuit. Typically, jumpers are used to set up or configure printed circuit boards like the motherboard.

 

•  Heat sink/heatsink (cooling system)

A heat sink is a passive heat exchanger that transfers the heat generated by parts of motherboard into a fluid medium like liquid or air. The fluid medium will dissipate away from the device. Thus, the temperature of the device is kept within a tolerable range. On the motherboard, the heatsink is usually used to cool CPU, GPU (graphics processing unit), chipsets and RAM modules.

• Clock generator

A clock generator is an electronic oscillator (circuit) that produces a clock signal for usage in synchronizing a circuit’s operation. The clock signal ranges between high and low frequencies, thus creating a metronome for the coordination of actions. 

 

 

THEORY - 114:- Precautions for SMPS Precautions for SMPS

Precautions for SMPS Precautions for SMPS

General Safety Guidelines when working on line powered equipment including: TVs, monitors, and microwave ovens. These guidelines are to protect you from potentially deadly electrical shock hazards as well as the equipment from accidental damage.

Note that the danger to you is not only in your body providing a conducting path, particularly through your heart. Any involuntary muscle contractions caused by a shock, while perhaps harmless in themselves, may cause collateral damage  ‐ there are many sharp edges inside this type of equipment as well as other electrically live parts you may contact accidentally.

The purpose of this set of guidelines is not to frighten you but rather to make you aware of the appropriate precautions. Repair of TVs, monitors, microwave ovens, and other consumer and industrial equipment can be both rewarding and economical. Just be sure that it is also safe!

• Don't work alone ‐ in the event of an emergency another person's presence may be essential.
• Always keep one hand in your pocket when anywhere around a powered line‐connected or high voltage system.
• Wear rubber bottom shoes or sneakers.
• Don't wear any jewelry or other articles that could accidentally contact circuitry and conduct current, or get caught in moving parts.
• Set up your work area away from possible grounds that you may accidentally contact.
• Know your equipment: TVs and monitors may use parts of the metal chassis as ground return yet the chassis may be electrically live with respect to the earth ground of the AC line. Microwave ovens use the chassis as ground return for the high voltage. In addition, do not assume that the chassis is a suitable ground for your test equipment!
• If circuit boards need to be removed from their mountings, put insulating material between the boards and anything they may short to. Hold them in place with string or electrical tape. Prop them up with insulation sticks ‐ plastic or wood.
• If you need to probe, solder, or otherwise touch circuits with power off, discharge (across) large power supply filter capacitors with a 2 W or greater resistor of 100‐500 ohms/V approximate value (e.g., for a 200 V capacitor, use a 20K‐100K ohm resistor). Monitor while discharging and/or verify that there is no residual charge with a suitable voltmeter. In a TV or monitor, if you are removing the high voltage connection to the CRT (to replace the flyback transformer for example) first discharge the CRT contact (under the insulating cup at the end of the fat red wire). Use a 1M‐10M ohm 1W or greater wattage resistor on the end of an insulating stick or the probe of a high voltage meter. Discharge to the metal frame which is connected to the outside of the CRT.
• For TVs and monitors in particular, there is the additional danger of CRT implosion ‐ take care not to bang the CRT envelope with your tools. An implosion will scatter shards of glass at high velocity in every direction. There is several tons of force attempting to crush the typical CRT. Always wear eye protection.
• Connect/disconnect any test leads with the equipment unpowered and unplugged. Use clip leads or solder temporary wires to reach cramped locations or difficult to access locations.
• If you must probe live, put electrical tape over all but the last 1/16" of the test probes to avoid the possibility of an accidental short which could cause damage to various components. Clip the reference end of the meter or scope to the appropriate ground return so that you need to only probe with one hand.
• Perform as many tests as possible with power off and the equipment unplugged. For example, the semiconductors in the power supply section of a TV or monitor can be tested for short circuits with an ohmmeter.
• Use an isolation transformer if there is any chance of contacting line connected circuits. A Variac (tm) is not an isolation transformer! The use of GFCI (Ground Fault Circuit Interrupter) protected outlet is a good idea but will not protect you from shock from many points in a line connected TV or monitor, or the high voltage side of a microwave oven, for example. A circuit breaker is too slow and insensitive to provide any protection for you or in many cases, your equipment. The GFCI may protect your scope probe from smoking if you accidentally connect its ground to a live chassis.
• Don't attempt repair work when you are tired. Not only will you be more careless, but your primary diagnostic tool ‐ deductive reasoning ‐ will not be operating at full capacity.
• Finally, never assume anything without checking it out for yourself! Don't take shortcuts!

PRACTICAL - 117 :- IDENTIFY THE TYPES OF OUTPUT CONNECTORS OF SMPS

 AIM :- IDENTIFY THE TYPES OF OUTPUT CONNECTORS OF SMPS

SMPS or PSU is the component that supplies power to your major computer components. the different types of connectors or cables of an SMPS that supply power to various computer components and devices..

 

20 + 4 Pin ATX / Motherboard Connector

 

This is the main ATX connector that supplies power to your motherboard and other components like RAM, Low-end graphics card, PCI cards that are connected to your motherboard. Earlier motherboards have 20 pin sockets only but now modern-day motherboards require 24-pin power connectors. Therefore nowadays all the SMPS comes with 24 pin detachable connector (20 + 4) that can be split into 20 pin and 4 pin cables.

 

CPU 4 + 4 Pin Connector

 

This is the 12 Volt connector that supplies power to your CPU or Processor. Some motherboards have 4 pins 12V CPU socket and some have 8 pins 12V socket, therefore most of the good power supplies come with 8-pin (4 + 4) detachable connectors which can be split into two 4 pin connectors.

 

SATA Power Connector

 

This power connector is used to power up SATA devices that mostly include Hard Disks, DVD Writers / Drives.

 

Floppy 4 Pin Connector

 

This 4 pin power connector is used to power floppy drives. Floppy Drives are not being used commonly, but in some cases they can prove very useful.

 

Peripheral 4 Pin Molex Connector

 

Peripheral 4 Pin Molex Connector is used to provide power to IDE devices and other peripherals like Fans, case lights etc. You can also use this Molex 4 pin connector to power other devices like SATA devices, Graphics cards etc. by the use of converters or adapters e.g. Molex to SATA power connector etc.

 

PCI-e 6 Pin / PCI-e 8 Pin Connector

 

PCI-e 6 Pin or PCI-e 6+2 Pin are 12 Volt Connectors that are used to provide power to mid to high range graphics cards that require extra amount of power for their working. Budget and low-end graphics cards do not need them as they draw their power from the motherboard PCI-Express x16 slot only. Older mid to high-end graphics card comes with PCI-e 6 Pin slot while the newer high-end graphics comes with PCI-e 8 Pin slot. The new PCI Express 8 Pin cable can provide a maximum of 150 Watts power which is double that of the PCI Express 6 Pin cable i.e. 75 Watts.

THEORY - 113 :- SMPS

 What is SMPS (Switch-Mode Power Supply)?

The full name of SMPS is Switch-Mode Power Supply. SMPS is defined in simple language when the need for electricity comes in the form of a switch. In which electrical energy is converted from one form to another with essential properties called SMPS. This power is used to obtain a regulatory DC input voltage from DC output or uncontrollable AC for power. SMPS is just as complex as any other power supply system. This is a power source used for loading.

SMPS is an important device for a wide variety of electrical and electronic devices. Which provides it with a source of power consumption specifically designed for electronic projects?

 

Working Principle of SMPS (Switch Mode Power Supply):

The working principle of switch-mode power supply topologies is as follows:

1. AC-DC Converter SMPS Working:

In this type of SMPS, the input supply is AC and in the output, we get DC supply. Rectifiers and filters are used to convert this AC power to DC. This uncontrollable DC voltage is given to the affected power factor correction circuits. This is because there is a low current pulse inside the rectifier around the peak of the voltage.

This includes high-frequency energy which influences to reduce the power factor. This is due to power conversion but we have used AC input instead of DC input supply. Therefore, a combination of rectifier and filter, this block diagram is used to convert AC to DC, and switching an operation is done using a power muffle amplifier.

MOSFET transistors use low resistance and are capable of resisting high currents. The switching frequency is chosen so that normal humans (above 20KHz) must be kept low and the operation of the switch is controlled using a PWM oscillator.

Again this AC voltage is given to the output of the transformer as shown in the figure or the voltage level goes down. After that, the output of this transformer is fixed and smoothed using the Output filter and corrector. The output voltage is controlled by the reaction circuit compared to the reference voltage.

Advantages of Smps:

The benefits of SMPS are as follows:

High efficiency:

The main advantage of SMPS is that it is more efficient than linear regulators. This is because the switching transistor dissipates a little power when it acts as a switch.

Compact:

Forms SMPS can be made more compact as a result of higher efficiency and lower levels of heat dissipation.

Costs:

Switch-mode is the value of a point making the power supply. Efficiency The high efficiency and switching nature of the design means that the standby power loss is often lower than that of transformers and this reduces costs.

Flexible Technology:

The SMPS feature can be used to provide high-efficiency voltage conversion to voltage step-up or “boost” applications or to step-down “buck” applications.

Applications of SMPS:

The application of SMPS is as follows:

•  The most common use of this is in computers.
•  Smps is used in security systems.
•  This is used in the railway system.
•  It is also used in battery chargers.
•  It is also widely used in machine tool industries.

 

Questionnaires  

1. What is the main function of SMPS?

SMPS is a switch-mode power supply. A type of high-frequency power conversion device and abbreviation for power supply device. Its function is to convert the required voltage or current level by various forms of architecture.

2. How does a switch power supply work?

SMPS works by turning the main power on and off at a high speed to reduce the voltage. In such a case the reduction in voltage depends on the ratio of time and off time. Switching happens very quickly, 10,000 times or faster per second.

3. What is SMPS short answer?

SMPS stands for Switch-Mode-Power-Supply. It is used in all types of computers. Today’s modern computers have an SMPS that takes the improved AC input power from the board in the house, by making a power factor correction and then converting the output to a single or lower voltage DC output.

4. What are SMPS Applications?

The application of SMPS is as follows:

·         The most common use of this is in computers.

·         Smps is used in security systems.

·         This is used in the railway system.

·         It is also used in battery chargers.

·         It is also widely used in machine tool industries.