Spare parts: Difference between revisions

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|Part Format
!Part Format
|Part  
!Part  
|Function/How to identify  
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|How to Test  
!How to Test  
|Salvageability  
!Salvageability  
|Buying Advice  
!Buying Advice  
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| Mains Circuit Board
| Internal switched mode power supply. -Found inside most mains digital devices: TVs/Desktop PCs/DVD players etc 
| *Exists to convert mains AC voltage to DC voltages required to run digital systems.
* Mains cable will usually connected directly to this
* bigger large size components will be present
|When turned on look for output voltages with a multimeter. Sometimes they are marked on the board.(or on casing with PC) Otherwise look for typical outputs like:
ON: 12V/24V
Standby: 5V
Control Signals: 3.3V
Desktop PSUs can be tricked into turning on without a motherboard by connecting two pins with a paper clip
|Intact and working desktop supplies can be used (for the rest of their lifetime) in other PCs.
Faulty boards can be desoldered for reusable parts like: capacitors, diodes, resistors, connectors, ICs and coils.
|Desktop PC enclosed PSUs usually follow ‘ATX’ standard - and are sold new - match wattage. Buy though respected outlet with long warranty and good reviews.
Internal PSU boards are usually bespoke and only available second hand. Match part numbers and device model number. Check pictures that connectors and components and layout are the same. Check eBay and look for high ranking sellers. Expect only a 30 day refund policy. 
 
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Revision as of 08:04, 22 June 2020

Spare parts are commonly needed when repairing electric or electronic items. Here we discuss which types of spare parts there are and how they can be sourced.


Types of Spare Parts

Original Parts

Original parts are made and distributed by the manufacturers themselves. Buying an original part gives you the certainty that it will fit the device. However, manufacturers often don’t produce spare parts, or limit availability to authorised repairers.


Third Party Parts

Where original spare parts aren’t available, third party ones often are if there is demand for them. Smartphone screens are a good example for this. But with this often comes some push back from manufacturers who want to restrict independent and third party repairers if they see them as a threat to their business.

Some third party spare parts are in fact identical to the genuine article and even come off the same production line. For example, a smartphone screen or battery manufacturer may simply continue a manufacturing run after satisfying the original order. However, the provenance of a spare part may be impossible to ascertain without a visit to the Far East, which in fact some reputable parts suppliers may actually have undertaken!

A lack of accountability can be a problem when buying third party parts, as it can be difficult to determine in advance that a spare part will be fit for purpose. Depending on where you buy, warranty and refund options may be limited.


Refurbished and Remanufactured Parts

Refurbished parts are spare parts that have been extracted from a used device and were repaired to be functional again. Note: "Refurbished" is not a protected term, anyone can use it and it can mean a variety of things. "Remanufactured" however is a protected term which means that the product meets all specifications of the original new product. With refurbished parts it can be difficult to tell what you get. Some parts might be refurbished in an unreliable way (e.g. reflowing a chip on the motherboard), others might have required only small repairs like a software reconfiguration and might work very well. When buying refurbished parts, it is good to look for a long warranty period and to buy from a reputable and accountable manufacturer.


Salvaging Parts

From some devices it is easier to salvage parts than from others. E.g. desktop PCs are designed to be more modular for the end user and individual parts are designed to widely adopted standards. So usually individual working parts from a desktop PC can be used as spare parts. In other devices, end user modification or salvaging is not promoted and reusing parts is more difficult, as they are more often bespoke for that particular device. For example, many televisions would have their own unique power supply and motherboard that could only be directly used again in that same model of TV.

Salvaged spare parts will have individual discrete components that can be used again in other devices, such as resistors, capacitors, diodes or transistors, though individually, few of these would be worth salvaging except by an electronics hobbyist.

See below for an overview of spare parts and where to find them.


Where to buy

Buying from manufacturer

Original spare parts will often be available directly via the manufacturer, but at a premium price. However there is no legal regulation that requires spare parts to be available to the public - that’s one of the reasons why we need a Right to Repair.


Spare parts suppliers

Several online shops have specialised in selling spare parts, both from the original manufacturers and from third party suppliers. The advantage of these online shops is that they often provide a warranty and good customer service. However especially for older or less common devices it might be difficult to find the desired spare part here.


Buying from eBay

eBay can be a good source of spare parts which are not available from the original supplier, and sometimes this is the only way to source a particular part. It is hard for sellers to maintain a good eBay reputation as their customer service usually favours the buyer side in any dispute and seller accounts can get banned after a few incidents. So most sellers will offer good products in order to receive good feedback.

However, as a wide range of people sell on eBay, some issues are common: items might be mislabelled or falsely claimed to be genuine, they might not meet EU/UK standards or they might have not been tested (e.g. when a circuit board has been taken from a cracked TV).


Potential issues and how to overcome them

Identifying fakes

When buying something labelled as an original spare part, always ask yourself: would the manufacturer still sell that item? It is unlikely that manufacturers provide spare parts for much longer than they are required to. This should not always be an excluding criterion though - it might be that the seller stocked up on the spare part himself when they were still commonly available. Surprisingly cheap prices can also be a warning sign that the piece might be fake.

It's especially important to beware of fakes where there may be safety issues. A good example is mains adapters, where inadequate insulation and isolation of the mains supply or underrated components may lead to electric shock or fire hazards.


Software Locks

Sometimes manufacturers place software locks on hardware, meaning that the device will only work with the components it originally came with. This stops repairers from using a component as a spare part in another device without illegally modifying the software. Manufacturers often claim security or safety reasons for this.

Also, manufacturers might deliberately stop servicing or providing support for software on older devices, citing escalating support costs or enhanced safety or security, but also to encourage the end users to replace them. The real motivation may be difficult to untangle with an open mind.


More things to consider when buying used

Some parts are more affected by excessive use over time than others. In computers and games consoles, GPUs and CPUs will often fail after excessive use over time if they are not properly ventilated and thereby cooled. When buying such used parts, you often don’t know how much they have been used already. Moving/mechanical parts (e.g. hard drives, drive belts, switches) will often be the first to fail so when you buy them used, you don’t know how much lifetime they still have in them.

BUT: If only second hand parts are available, don’t hold your breath - look for a returns policy and good seller feedback record.




Spare Parts overview

Part Format Part Function/How to identify How to Test Salvageability Buying Advice
Mains Circuit Board Internal switched mode power supply. -Found inside most mains digital devices: TVs/Desktop PCs/DVD players etc *Exists to convert mains AC voltage to DC voltages required to run digital systems.
  • Mains cable will usually connected directly to this
  • bigger large size components will be present
When turned on look for output voltages with a multimeter. Sometimes they are marked on the board.(or on casing with PC) Otherwise look for typical outputs like:

ON: 12V/24V Standby: 5V Control Signals: 3.3V Desktop PSUs can be tricked into turning on without a motherboard by connecting two pins with a paper clip

Intact and working desktop supplies can be used (for the rest of their lifetime) in other PCs.

Faulty boards can be desoldered for reusable parts like: capacitors, diodes, resistors, connectors, ICs and coils.

Desktop PC enclosed PSUs usually follow ‘ATX’ standard - and are sold new - match wattage. Buy though respected outlet with long warranty and good reviews.

Internal PSU boards are usually bespoke and only available second hand. Match part numbers and device model number. Check pictures that connectors and components and layout are the same. Check eBay and look for high ranking sellers. Expect only a 30 day refund policy.