58 APPENDIX A
Proximity to Hazardous Voltages
This information is provided for the benefit of manufacturers of PCs which include a PC Card slot. Users should verify that their PC has been constructed in accordance with the following guidelines.
In order to comply with safety regulations there must be adequate separation between Netopia ISDN PC Card and adjacent modules.
Except at the edge connector which plugs into the host's expansion slot, minimum clearance and creepage distances must be maintained between Netopia ISDN PC Card and other parts of the host, including other installed cards. Clearance is the shortest distance between two points measured directly through the air. Creepage is the shortest distance between the same two points measured along surfaces.
The minimum clearance and creepage distances vary according to the voltage level present in the host PC or in cards installed in it. These figures are listed in the following table.
Voltage used or generated by other parts of | Clearance | Creepage | |
the host or expansion card Vrms or Vdc | mm | mm |
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|
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up to 50 | 2.0 | 2.4 | (3.8) |
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|
|
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up to 125 | 2.6 | 3.0 | (4.8) |
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|
|
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up to 250 | 4.0 | 5.0 | (8.0) |
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|
|
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up to 300 | 4.0 | 6.4 | (10.0) |
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|
|
|
The creepage distances apply when installed in a normal office environment. The creepage distances shown in parentheses apply where the local environment within the PC is subject to conductive pollution or dry