Digital Equipment DEC WANrouter 90, Руководство пользователя, Страница: 111 / 121

D–5 U.K. Required Information
D.4 Module Isolation
Except at the connector that plugs into the host, clearance and creepage distances of
Xmm and Ymm, as listed in Table D–2, must be maintained between the approved
module and other parts of the host, including expansion cards. Clearance is the
shortest distance in air between two points. Creepage is the shortest distance along a
continuous surface between those same two points.
Table D–2: Clearance and Creepage Distances
Clearance Xmm Creepage Ymm Vrms or Vdc
2.0
2.6
4.0
4.0 2.4 (3.8)
3.0 (4.8)
5.0 (8.0)
6.4 (10.0) Up to 50
Up to 125
Up to 250
Up to 300
NOTE
The distances shown in parentheses apply in an un-
controlled environment where heat, humidity, and
temperature may fluctuate.
D.5 Equipment Between the Approved Module and a Digital Circuit
If any other equipment, including cables or wiring, is to be connected between the
approved module and the point of connection to any particular digital circuit, that
equipment must conform as follows:
•
The overall transmission characteristics of all other equipment must not have
any material effect on the electrical conditions between the equipment and the
digital circuit.
•
All other equipment must comprise only the following:
1. Approved equipment, which may be subject to limitations on its use, for
the purpose of connection between it and a particular digital circuit.
2. Cable or wiring that complies with a code of practice for the installation
of equipment covered by this standard or other requirements that may be
applicable.