One of my customer asked me why power cord for some household appliances doesn’t have EGC?
In Europe they’re labeled class ll with square inside square symbol that means doble insulated.In USA i Guess UL listing is enough but no sure.
Someone nows for sure?
From OSHA "But a double insulated tool is made differently. It does not have a casing or housing made from conductive material.
Instead it is made of plastic or some other material that does not conduct electricity. This extra layer of electrical insulation provided by the non-conductive casing or housing negates the need for a grounding wire and prong on the power cord. You can tell if the tool you are using is a double-insulated variety. Just look at the manufacturer’s data plate or sticker affixed to the tool, and if it is double insulated and you may see the words “Double Insulated” printed there. Or you may see the international symbol for a double insulated tool on the label; it is a “square-within-a-square” symbol (refer to handout for an example).
And in many cases you may see both the wording and the box-in-box symbol displayed on the label. But don’t think for a minute that using a double insulated tool means you are always going to be protected from electrocution. That is because any breach in the tool’s plastic casing or housing creates a potential pathway for electricity to travel through and make contact with your skin.
Such conditions can occur if the tool casing or housing is cracked, which can happen if the tool is dropped onto a hard surface. A breach can also occur if any screws or other fasteners that hold the casing or housing parts together become loose and allow them to separate. "
Thanks Paul, didn’t know that,don’t you think for those reasons you explain,all power cord should came with EGC?After reading you comments sound unsafe of those accidents happening
Well, thats for the UL/ANSI Standards to decide and there are some sharps cats on those communities. I just stick to encoring the codes and met the manufacturer do their thing.
In the US we have the same. Different listing standards for appliances provide for a Double Insulated design option for the cord.
From OSHA "But a double insulated tool is made differently. It does not have a casing or housing made from conductive material. Instead it is made of plastic or some other material that does not conduct electricity. This extra layer of electrical insulation provided by the non-conductive casing or housing negates the need for a grounding wire and prong on the power cord. You can tell if the tool you are using is a double-insulated variety. Just look at the manufacturer’s data plate or sticker affixed to the tool, and if it is double insulated and you may see the words “Double Insulated” printed there. Or you may see the international symbol for a double insulated tool on the label; it is a “square-within-a-square” symbol (refer to handout for an example). And in many cases you may see both the wording and the box-in-box symbol displayed on the label. But don’t think for a minute that using a double insulated tool means you are always going to be protected from electrocution. That is because any breach in the tool’s plastic casing or housing creates a potential pathway for electricity to travel through and make contact with your skin. Such conditions can occur if the tool casing or housing is cracked, which can happen if the tool is dropped onto a hard surface. A breach can also occur if any screws or other fasteners that hold the casing or housing parts together become loose and allow them to separate. "
Thanks Paul, didn’t know that,don’t you think for those reasons you explain,all power cord should came with EGC?After reading you comments sound unsafe of those accidents happening
Well, thats for the UL/ANSI Standards to decide and there are some sharps cats on those communities. I just stick to encoring the codes and met the manufacturer do their thing.