Pat testing: Class 2 printers and laptop power packs????

[jameswalters33]

Hi I'm a little confused, sure this has been asked on here before but I'm pretty new to forums

Could you tell me if the following about PAT testing is correct

Class I printer, plug in printer IEC Lead into pat tester test as a lead Earth, Insulation and Polarity. Plug lead back into printer find earth on metal part of printer and test as Earth and Insulation res?

Class II printer I'm a little confused PAT TEST mickey mouse lead earth, insulation and polarity, what about the power pack and the printer?

Also do mobile phone Class II chargers need to be pat tested or will a visual do?

Laptop chargers do they need PAT Testing I know you need to test the lead but will a visual do for the power pack?

Also is a laptop power pack charger class I or II they never say isit by the lead it takes as I've seen class I and class II leads going into these laptop power packs

Many Thanks

 

[grantr37]

Class 1 Printer ( the big ones like Xerox/seiko/mitsubishi) test the IEC Lead @ 25A then check the fuse size, then use one of the Rivets or screws on the back for the probe test for earth bonding......don't use the metalwork on the Network card where the Cat 5 cable goes into it from the office network (the Plastic RJ11 connector with network cable) as this will fry the network card...use another bit of metalwork on the back....
Always unplug the network cables from the printer as they will cause incorrect earth readings as the outer thin metal sheath (screen) in the cable will connect the printer earth/case earth directly to the PC( The PC power Supply earth, Case that is connected to this, as well as the mainboard/motherboard) that it is connected to....

Making sure that the network connector cables are removed during testing will also save you from damaging any Laptop/Netbook that is connected, the network card in those is 99%of the time part of the mainboard (or as Laptop techies call it the "Logic Board") and is pricey to repair if you don't do repairs yourself...


Class 2 printers (Plastic Desktop ones like Epson or KODAK ones) take out the figure 8 lead and insulation test it with an adapter, then check that the fuse in the plug is the correct size(such as 5A, or 3A and not a 10A or 13A fuse) give it a quick once over to make sure no broken open plastic around the mains parts as a visual.....

Mobile phone Adaptors/chargers are a visual check only as they are SELV straight from the plug pins into an isolated transformer then a rectifier and regulator inside, encompassing some switched mode power supply circuitry...output is low voltage so its just a visual check...

Laptop chargers: check that the power pack box/case is not broken or split open, then check that the low voltage output lead that goes into the laptop is not split open, so as to avoid fraying of the outer part of the conductor ( these are mostly small co-axial flex with the inner core as +Ve and the outer stranded sheath/conductor as GND -Ve) from causing overheating, as if it is hanging on by a few strands it can heat up during use when it will be carrying a reasonable bit of current (usually anything up to 15A DC) and melt/start a fire......if the charger case and the outgoing fixed/built in lead are ok, then check the IEC lead (or cloverleaf lead-adapters to fit PAT machines are on ebay for about £3) using a 25A IEC lead test on the PAT tester, check that the Fuse is the right one (almost always a 10Amp one, sometimes a 5A on Netbook chargers, Never Ever a 13A) then that's you done apart from the sticker and paperwork..


Laptop chargers are almost always Class 1 (3 pin input plug) Netbook (miniature laptops) are 50% figure 8 leads(Class2) and 50% Class 1 (on an IEC 3 pin supply lead) depending on the manufacturer...

 

[Deleted member 9648]

Class 1 Printer ( the big ones like Xerox/seiko/mitsubishi) test the IEC Lead @ 25A then check the fuse size, then use one of the Rivets or screws on the back for the probe test for earth bonding......don't use the metalwork on the Network card where the Cat 5 cable goes into it from the office network (the Plastic RJ11 connector with network cable) as this will fry the network card...use another bit of metalwork on the back....
Always unplug the network cables from the printer as they will cause incorrect earth readings as the outer thin metal sheath (screen) in the cable will connect the printer earth/case earth directly to the PC( The PC power Supply earth, Case that is connected to this, as well as the mainboard/motherboard) that it is connected to....

Making sure that the network connector cables are removed during testing will also save you from damaging any Laptop/Netbook that is connected, the network card in those is 99%of the time part of the mainboard (or as Laptop techies call it the "Logic Board") and is pricey to repair if you don't do repairs yourself...


Class 2 printers (Plastic Desktop ones like Epson or KODAK ones) take out the figure 8 lead and insulation test it with an adapter, then check that the fuse in the plug is the correct size(such as 5A, or 3A and not a 10A or 13A fuse) give it a quick once over to make sure no broken open plastic around the mains parts as a visual.....

Mobile phone Adaptors/chargers are a visual check only as they are SELV straight from the plug pins into an isolated transformer then a rectifier and regulator inside, encompassing some switched mode power supply circuitry...output is low voltage so its just a visual check...

Laptop chargers: check that the power pack box/case is not broken or split open, then check that the low voltage output lead that goes into the laptop is not split open, so as to avoid fraying of the outer part of the conductor ( these are mostly small co-axial flex with the inner core as +Ve and the outer stranded sheath/conductor as GND -Ve) from causing overheating, as if it is hanging on by a few strands it can heat up during use when it will be carrying a reasonable bit of current (usually anything up to 15A DC) and melt/start a fire......if the charger case and the outgoing fixed/built in lead are ok, then check the IEC lead (or cloverleaf lead-adapters to fit PAT machines are on ebay for about £3) using a 25A IEC lead test on the PAT tester, check that the Fuse is the right one (almost always a 10Amp one, sometimes a 5A on Netbook chargers, Never Ever a 13A) then that's you done apart from the sticker and paperwork..


Laptop chargers are almost always Class 1 (3 pin input plug) Netbook (miniature laptops) are 50% figure 8 leads(Class2) and 50% Class 1 (on an IEC 3 pin supply lead) depending on the manufacturer...

My pat tester IR tests between line/neutral joined together and earth,therefore IR testing a 2core lead would be pointless. Only IR test a class 2 printer using the auxillary IR probe onto any exposed metal....if the printer has no exposed metal visual only

 

[grantr37]

you can get adapters for figure 8 2 core leads...as well as cloverleaf adapters and others for lighting rigs and stage equipment, industrial commando sockets etc...

 

[ohreally]

Not enough information.

Depending on the type of premises, C2 equipment may require no combined inspection and testing (hotels, offices and shops) - read through your CoP.

 

[markc123]

or just stick a sticker on it as passed and charge £0.10 which everyone seems to be doing these days.

"my appliance isnt working and uve passed it recently" "....it must of broke / become dangerous since i was last their then because it tested out fine on the day, and my equipment is calibrated"

 

[grantr37]

Echuta

 

[jameswalters33]

OK thanks for the advice thats pretty much what im doing with the class I printers

Class II just test the lead basically? but the printer also needs a visual so a sticker for each?

What about if you find a fig 8 lead going in to power pack then to the printer?

 

[hazelm]

Not enough information.

Depending on the type of premises, C2 equipment may require no combined inspection and testing (hotels, offices and shops) - read through your CoP.

Is there not a proviso? May require no combined inspection and testing provided the formal visual inspection (which is recorded) is made? This point is made also on the HSE website.

Also, some powerpacks for laptops and printers do not have the double insulated box on them. (Only if an appliance has the double insulated box can it be considered as class 2). If so, the earth bond test is to be done. Added check, if the earth pin is metal, think about earth.

 

[Grizzly01]

My pat tester IR tests between line/neutral joined together and earth...

As does every PAT tester

therefore IR testing a 2core lead would be pointless.

Quite right. A fact that seems to repeatedly escape many

you can get adapters for figure 8 2 core leads...as well as cloverleaf adapters and others for lighting rigs and stage equipment, industrial commando sockets etc...

Still pointless IR testing a 2-core mains lead.

 

[Grizzly01]

Also, some powerpacks for laptops and printers do not have the double insulated box on them. (Only if an appliance has the double insulated box can it be considered as class 2). If so, the earth bond test is to be done. Added check, if the earth pin is metal, think about earth.

Here we get into uncertain territory.
There are 3 types of power supply of the style being discussed:

1) Class II, bearing the appropriate construction mark. Most usually fully insulated, but if one is hell-bent on doing an Class II IR test, then the metal on the ELV output connector barrel can be used as your 'unearthed metal' to connect the probe to.

2) Class I, with the earth connection from the 230V inlet continuous to the ELV output connector.
Easy to do an earth bond test, and obviously a Class I IR test.

3) Class I, but the earth connection is not continuous to the ELV output connector. It will terminate within the body of the unit, so impossible to do an earth bond test. The metal of the ELV barrel is essentially double-insulated from the live parts.

It's usually type 3) that causes most confusion, and isn't adequately addressed in guidance such as the IET CoP.

My opinion: miss out the earth bond test, and make a note of the this, and the reason why, in the test records, but still do a Class I IR test.

 

[hubsy]

This confusion with class 1 SMPS is a right pain.
How do you know if the outer of the barrel is supposed to be connected to the incoming earth connection.
If it is supposed to be connected, how can we tell that it hasn't gone open circuit? as apposed to class 1 that isn't connected in the first place.