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Uninsulated live parts clearance 1
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I had seen these tables, but the distances were a far cry from the NEC's in Table 408.56, and with cause: they are related to section 36, High Voltage Installations.
I am specifically looking for 600V clearances (or under 1000V). Should have been more specific about it.
I am specifically looking for 600V clearances (or under 1000V). Should have been more specific about it.
"...I am trying to find an Canadian code equivalent to the table for minimum spacings found in NEC 408.56."
I have the following information for your consideration.
1. Reference CSA C22.1:21. Unfortunately, there is no index on the term "creepage and clearance distance" at the end of the document; making it difficult to pinpoint the relevant page where the subject is mentioned.
2. However, see Bare busbar 12-2600 d) ii) "... with minimum clearance across insulating surface between bus of opposite polarity of not less than 50mm, and 25mm between busbars and any grounded surface; and ...on ".
3. See (non-mandatory part of the Code) appendix K extract from IEC 60364-1... Reference other parts of IEC where creepage and clearance distances are very well defined with detail recommendation etc...
Che Kuan Yau (Singapore)
I have the following information for your consideration.
1. Reference CSA C22.1:21. Unfortunately, there is no index on the term "creepage and clearance distance" at the end of the document; making it difficult to pinpoint the relevant page where the subject is mentioned.
2. However, see Bare busbar 12-2600 d) ii) "... with minimum clearance across insulating surface between bus of opposite polarity of not less than 50mm, and 25mm between busbars and any grounded surface; and ...on ".
3. See (non-mandatory part of the Code) appendix K extract from IEC 60364-1... Reference other parts of IEC where creepage and clearance distances are very well defined with detail recommendation etc...
Che Kuan Yau (Singapore)
Everything is insulated - even if only by the surrounding medium. Look at how much energy (voltage) is required to break down the medium to understand how much straight line clearance is required.
Creepage is another issue - it's usually easier to "creep" (cross along the edge of a surface) than to cross an open gap. That means creepage distance is LONGER than clearance - which assumes a straight line.
Basic rule of thumb: at sea level, with 50% humidity, a reasonable clearance through air is 0.001 inch per volt. A reasonable creep distance is twice that.
Converting energy to motion for more than half a century
Creepage is another issue - it's usually easier to "creep" (cross along the edge of a surface) than to cross an open gap. That means creepage distance is LONGER than clearance - which assumes a straight line.
Basic rule of thumb: at sea level, with 50% humidity, a reasonable clearance through air is 0.001 inch per volt. A reasonable creep distance is twice that.
Converting energy to motion for more than half a century
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I have the following additional information, for your consideration.
1. Reference IEC 60364-5-53, 60664-1 and 60664-2-1...; where Clearance and Creepage distance are well defined. Recommended values are listed.
2. Definition: a) Clearances are dimensioned to withstand the impulse voltage...
b) Creepage distances are influence by Voltage, Pollution, shape of insulating surface, Insulating material...
Che Kuan Yau (Singapore)
1. Reference IEC 60364-5-53, 60664-1 and 60664-2-1...; where Clearance and Creepage distance are well defined. Recommended values are listed.
2. Definition: a) Clearances are dimensioned to withstand the impulse voltage...
b) Creepage distances are influence by Voltage, Pollution, shape of insulating surface, Insulating material...
Che Kuan Yau (Singapore)
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