小米 发表于 2012-11-8 15:26

DSH 754 Screws, Creepage distance and clearance


http://decisions.iecee.org/icons/ecblank.gif DSH 754
Screws, Creepage distance and clearance
21.19
60745-1(ed.4)


Standard(s):
IEC 60745-1:2006
Sub-clause(s):
21.19
No. Year
DSH
754
2010
Category: TOOL Developed by: ETF 1
Subject:
Screws, Creepage
distance and clearance
Key words:
- Screws
- force
- Creepage distance and
clearance
Approved at the 2010 CTL
Plenary Meeting
Question:
1)
“Tools shall be so designed that the protection against electric shock is not affected when
screws intended for replacement from the outside during routine servicing are replaced by
screws having a greater length.”
What screw should be used? Only the screws from equipment under test or any other
possible screw?
2)
“Compliance is checked by inserting longer screws, without appreciable force, after which
creepage distances and clearances between live parts and accessible metal parts shall not
have been reduced below the values specified in 28.1”
What force is to be applied?
Decision:
1)
The screw originally used on the equipment and any other longer screw that can be found
on the equipment is to be used.
2)
The force values in Table 9 shall be applied.

页: [1]
查看完整版本: DSH 754 Screws, Creepage distance and clearance