Specifying durability and repair for laptop computers

Transcription

1 Case study Specifying durability and repair for laptop computers June 2011 A case study of a Hewlett-Packard notebook to illustrate and encourage the durability and repair of laptop computers.

2 Specifying durability and repair for laptop computers 2 Introduction This case study complements the buying specifications for laptops that have been developed by WRAP to assist buyers and manufacturers procure and produce products that last longer, can be more easily repaired and that lead to lower environmental impacts. The HP (Hewlett-Packard) 6530b notebook was used to demonstrate the practical application of many of these good practice specifications. The study assesses the key features that contribute to extending the product s lifetime through durability and repair by highlighting the most beneficial measures, some of which can be relatively simple to achieve. The buying specifications (see separate publications) include further detail for companies wanting to take a more ambitious approach and deliver greater environmental benefits. The specifications were developed by assessing a range of laptop and notebook computers through discussions with manufacturers, designers and repairers, and also through carrying out teardown on a range of products to identify design features that facilitate repair. Product information The HP 6530b is a corporate notebook with a widescreen 14 diagonal display and a dual core processor. It weighs 2.41kg including the DVD/CD drive. There is an option to install a webcam and the laptop represents the high-cost machine and retails at around 650. The model comes with a 1 year manufacturer s guarantee, although newer HP corporate models such as the Elitebook series come with a 3 year parts and labour guarantee. This longer-term repair warranty typically exceeds that of most models of a similar specification and helps to ensure that repair takes place in the event of failure rather than disposal.

3 Specifying durability and repair for laptop computers 3 Durability Laptop lifetime issues Due to the mobility of laptops they are more prone to general damage and hardware failure than desktop models. It is reported by Square Trade 1 that on average 7% of laptops fail due to hardware malfunction or accidental damage within the first year of use, however this rises sharply to nearly 20% by year two, and by the third year one third have failed. The most common faults and associated issues reported by independent repairers in the US, relevant studies and by Gartner IT 2 3 and Square Trade 4 are: LCD (liquid crystal display) screens - difficult to remove from case lids and can break; lid hinge and bracket damage - due to fatigue by constant use; hard drive and motherboard (main printed circuit board) faults DC (direct current) damage to sockets - often plastic connectors where the power lead is exposed; overheating of electronic components such as hard-drives and printed circuit board components; keyboard damage - particularly individual keys that are not available to purchase; cost of key spare parts - such as screens and printed circuit boards that make repair uneconomical; and overheating due to insufficient ventilation - often fewer fans are used due to space restrictions and ventilation slots become blocked. Ensuring the reliability of electronic devices is becoming increasingly challenging, attributable to the rate of technological advancement and added functionality which can lead to: increased complexity of electronic circuits; increased power requirements (e.g. for video); and new components and material technologies

4 Specifying durability and repair for laptop computers 4 A typical laptop is intended for mobility and is therefore regularly subject to potential damage by impact, compression loads, vibration (for example when used on trains) and liquid spillages. HP s product user manual specifies the operating limits for voltage, temperature, relative humidity, shock and vibration for safe operation of the laptop, helping the user to reduce potential damage. The laptop has been designed to withstand these stresses as far as possible to extend lifetime and reduce the need for repair. Mechanical robustness Vulnerable parts Design and location of key components is a key consideration to prevent damage, and hinges of the HP 6530b are positioned away from its exposed edges and are protected by a cover. The power socket is recessed on the side of the casing for protection and the on-off button is away from the edge and close to the keyboard. Exterior casing The casing is made from PCABS (a poly-carbonate acrylonitrile butadiene styrene blend). This is considered to be a robust and suitable material ideal for this type of application. The polymer is clearly labelled as shown in figure 1, which assists the recycling process during disassembly. Figure 1 Material (PCABS) plastic labelling on casing The mouldings are designed to withstand breakage and provide protection if dropped, and fixings are located in areas that are less prone to damage such as away from corners and edges. The wall thickness of the casing is sufficient to provide good rigidity which reduces flexing during use

5 Specifying durability and repair for laptop computers 5 and offers protection to internal parts. The covers used for accessing components are also sufficient to resist flexing and the laptop shows limited deflection of the top moulding when pressure is applied around the mouse pad area. Component housings All removable parts such as the RAM (random access memory), hard drive (storage memory) and WLAN (wireless local area network) module are secured to the casing and have a cover that is screwed in place. This eliminates the potential for parts to spring out of their mounts and be exposed to damage. The touch pad, which undergoes heavy use during the lifetime of the laptop, is secured with a metal bracket screwed to the chassis by six bosses. The main screws securing the two halves of the chassis together have an adhesive applied to the threads which forms an instant seal and prevents loosening by vibrations, stress and shock, whilst also allowing easy disassembly. Figure 2 Touch pad fixing from manual

6 Specifying durability and repair for laptop computers 6 Electrical robustness Connectors and leads The keyboard and LED (light emitting diode) boards are connected to the main circuit board by a ZIF (zero insertion force) connector which prevents damage caused by applying force upon insertion and extraction. All of the connectors are securely fixed with Figure 3 Wire clip positions from manual the leads routed around the inside of the case and clipped or taped where necessary. The length of the wiring between components is kept to a minimum to prevent movement of the cables, as over time this may lead to failure of the connectors or soldered joints. As an example of good practice, the wire clips identified with a 5 below are used to hold the wire for the wireless antenna cables. Cooling The HP model ensures adequate cooling through the use of an internal fan which draws air in through four underside inlets, and exhausts warm air through a dedicated slot in the left side (illustrated as 2 below). Having several air inlets helps to prevent obstruction when the machine is used on a lap or a cushion for example. Figure 4 Side cooling vent from manual

7 Specifying durability and repair for laptop computers 7 Repair The fan is controlled by a temperature sensor designed to automatically operate to protect it from high temperatures. In order to ensure the air flow is not interrupted, HP recommend there is a minimum 3 clearance on the left side of the computer when in use, and that it is placed on a flat surface so the underside vents are not obstructed. Fault diagnosis and technical support Basic information for the diagnosis of faults is provided by HP in the user guide and also on a diagnostic page on their website 5 which includes information on: Microsoft Windows error messages; error conditions such as unexpected shutdowns; and faults with the display, drives, keyboard and sound. In addition there is a software diagnostics menu available at startup which provides test information on: start-up: verifies the system components needed for starting the computer; run-in: a comprehensive check on system memory; and hard disk: runs a comprehensive test on all hard drives in the system. This allows the user to verify that all the key operating components are working correctly and identify any faults. Hewlett- Packard also provides a technical support web centre for this product 6. The self-diagnostic software combined with the customer support assists users in identifying the cause of an error and enables them to either take action to remedy the fault or use the information to inform a repairer. 5 ng=en&cc=uk&prodtypeid=321957&prodseriesid= &taskid= us&prodtypeid=321957&prodseriesid= &lang=en&cc=us

8 Specifying durability and repair for laptop computers 8 A comprehensive manufacturer s maintenance and service guide (or manual) can be downloaded 7 from HP s website to assist professional repairers and this includes: exploded views of all the key parts (figure 5); photographs detailing buttons, sockets and access covers; illustrated parts catalogues; sequential parts number listings of available parts; step-by-step guide to replacing parts; listing of screw types and locations; connector pin alignments; and power cable requirements. Figure 5 Exploded view of major parts - from manual 7 c pdf

9 Specifying durability and repair for laptop computers 9 Parts availability HP s online spare parts store 8 list prices of available parts. Availability, together with the price of parts can be a significant barrier to repair, particularly in the independent repair sector which deals with repairs undertaken when the guarantee period has expired. HP facilitate repair by making all parts available for five years after the model production has ceased. Access for repair and replacement The most commonly replaced parts are easily accessible from the underside of the laptop. Each of the key components can be accessed by individual panels (figure 6), clearly marked and referenced in the online user guide 9 and the manual. 10 Figure 6 Parts access locations - from manual The panels that allow access to each component are clearly labelled with a symbol representing the component (below). The manual also highlights the screws here a reference key for the symbols can also assist the process E91CF0A =en&cc=us&taskid=&contenttype=supportmanual&prodseriesid= &p rodtypeid=321957# c pdf

10 Specifying durability and repair for laptop computers 10 Figure 7 Screws and associated parts markings (indicated by arrows) These features make replacement of parts easier and quicker and while a number of laptop manufactures use similar methods to access panels, this product demonstrates best practice by also labelling the covers. The hard drive, RAM, WLAN and Bluetooth modules, and DVD/CD drive are all simply secured with screws allowing the repairer to replace or upgrade the components without the need for specialist tools. A web page 11 on HP s site provides a step-by-step guide to replacing these key components. Any tools required for disassembly of more complex assemblies are listed along with recommendations on the handling of components, cables and connectors to prevent damage including that from electrostatic discharge. All the parts are described as safe to replace by a general user, provided the manual guidance on safe handling of components, cables and connectors is followed. To demonstrate the level of ease with which each key part can be accessed and replaced, as part of the assessment several parts were replaced following the instructions in the manufacturer s user guide and the process is described below =en&cc=uk&prodtypeid=321957&prodseriesid= &tx=6530b

11 Specifying durability and repair for laptop computers 11 Hard drive Two screws secure the hard drive cover to the chassis and a further screw enables it to be removed from the casing. Four screws then enable the hard drive to be removed from its mounting bracket. These stages were found to be simple and relatively quick, taking less than 5 minutes. Figure 8 Removal of hard drive from manual Bluetooth module The Bluetooth cover is held in place by a single screw. Beneath this there is a clip-on lead and the module can then be removed from the casing. This takes only a minute or two to complete. DVD/CD drive Access here is a little more complicated as it requires a Torx screwdriver. It would be preferable to use the same screws and screw-head size for all the covers to avoid tool changes and decrease replacement time. Two further screws then release the drive from the retaining bracket and this takes about 2 minutes to complete. Figure 9 Removal of Bluetooth cover and module

12 Specifying durability and repair for laptop computers 12 RAM and WLAN modules The RAM memory slot and WLAN are easily accessed by the same cover and one standard screw. The RAM is then simply unplugged and a replacement inserted. The RAM takes approximately a minute to replace and the WLAN about 2 minutes. The WLAN is accessed by two screws and the antenna lead is removed, and this was found to be a simple operation. Figure 10 Removal of cover for RAM and WLAN Figure 11 Removal of WLAN - from manual LCD screen The LCD screen is one of the more complex assemblies to replace, although the process is simplified by following the step-by-step guidance in the manual. In the HP 6530b, the keyboard and switch cover are removed to access the screen. The screen is then detached from various leads and its hinges, the screen front bezel, the screen brackets, the antenna leads and the inverter (screen controller) cable. This sequence is clearly explained in the manual using text and photographs and this operation takes around 20 minutes.

13 Specifying durability and repair for laptop computers 13 Figure 12 Some of the LCD screen removal stages While this process is relatively complex it was found to be easier in the HP model than some of the other manufacturer s models assessed, where the whole keyboard base moulding needed to be removed to allow access and this should be avoided. Replacing the LCD screen would be one of the more expensive tasks carried out by a repairer. A new LCD screen from independent stockists was found to cost between (based upon compatible screens from a range of online vendors.) w,

14 Specifying durability and repair for laptop computers 14 Conclusion The HP 6530b laptop illustrates some of the key specifications that contribute to durability and repair. This model is designed to be robust and durable, and also enables many of the major components and assemblies to be easily removed for replacement or upgrade which is critical to extending the product s life. Parts that would usually need replacement by a qualified repairer such as the LCD screen, can be replaced by the user following the clear step-by-step guidance in the manual. Laptop durability and repair in most cases can be addressed by identifying and implementing relatively straightforward and easy to achieve specifications. Measures such as ensuring good availability of spare parts that are easy to access and replace on the machine can provide significant benefit and encourage repair and longer product life. Some easy to replicate specifications for repair include: access panels that are clearly labelled and easy to open; minimising the number of standard screws for access panels and internal components; and ensuring the availability of key critical spare parts at reasonable prices. Enabling user and repairer online access to: the user guide; diagnostic information of faults; detailed parts listings and support; and step-by-step repair manuals with exploded views and photographs. Specifying laptops that are robustly constructed, are more durable and last longer by: using robust casing and chassis; protected external parts from damage; and securely fixing internal components. Specifying laptops that have good electrical design to reduce the likelihood of parts failure by: careful wiring runs and clips; using zero insertion force connectors; ensuring adequate component cooling by heat sinks and thermostatically controlled fans; and providing adequate air inlets and outlets in considered locations that prevent obstruction.

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