|
Device Areas
|
B
|
R
|
S
|
F
|
|
Primary winding to
primary winding
|
|
|
|
x
|
|
Primary winding to
grounded screen
|
x
|
|
|
|
|
Primary winding to insulated body
|
x
|
|
|
|
|
Primary winding to double-insulated body
|
|
x
|
|
|
|
Primary winding to hazardous secondary
|
x
|
|
|
|
|
Primary winding to ELV or grounded SELV
|
x
|
|
|
|
|
Primary winding to ungrounded SELV
|
|
x
|
|
|
|
Grounded screen to insulated body
|
|
|
|
x
|
|
Grounded screen to double-insulated body
|
|
|
|
x
|
|
Grounded screen to hazardous secondary
|
x
|
|
|
|
|
Grounded screen to ELV or SELV
|
|
|
|
x
|
|
Double insulation to double-insulated body
|
|
|
|
x
|
|
Double insulation to hazardous secondary
|
|
x
|
|
|
|
Double insulation to ELV
|
|
|
x
|
|
|
Double insulation to SELV
|
|
|
|
x
|
|
Hazardous secondary to ELV
|
x
|
|
|
|
|
Hazardous secondary to grounded SELV
|
x
|
|
|
|
|
Hazardous secondary to ungrounded SELV
|
|
x
|
|
|
|
ELV to grounded SELV
|
|
|
|
x
|
|
Grounded SELV to ungrounded SELV
|
|
|
|
x
|
|
TNV to primary
|
|
x
|
|
|
|
TNV to grounded or ungrounded SELV
|
x
|
|
|
|
|
TNV to ELV
|
|
|
x
|
|
|
TNV to grounded hazardous secondary
|
|
x
|
|
|
|
TNV to ungrounded hazardous secondary
|
|
x
|
x
|
|
|
Table I. Types of insulation required between device areas: B = basic,
R = reinforced, S = supplementary, and F = functional.
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