Those, too. I didn't say that the DP switch is a safety issue, it's a 
reliability or durability issue. 
 
When IEC/EN 60065 required DP switches on TVs, I pointed out the implications 
of a short-circuit, and proposed that the product's fuse be connected upstream 
of the switch. Although I was 'Head of Audio', not TV, that was adopted, with a 
label 'LIVE FUSE'.
 
With regard to the stored energy in L-N and L-E capacitors, the maximum amount 
is limited in safety standards, not necessarily directly in joules.
 
With best wishes DESIGN IT IN! OOO – Own Opinions Only
 <http://www.jmwa.demon.co.uk/> www.jmwa.demon.co.uk J M Woodgate and 
Associates Rayleigh England
 
Sylvae in aeternum manent.
 
From: John Allen [mailto:john_e_al...@blueyonder.co.uk] 
Sent: Saturday, January 28, 2017 4:58 PM
To: EMC-PSTC@LISTSERV.IEEE.ORG
Subject: Re: [PSES] Double Pole Mains Switches, Cord Connected Products
 
FWIW, the same applies to the 10/16A 2-pin plugs, most of which also reversible.
 
However, there are some national exceptions, notably in Denmark, Switzerland & 
Italy which have some unique plug/socket combinations of their own – some of 
those are reversible and some are not.
 
Not sure I agree with there being an inherent safety issue in fitting d/p 
switches to appliances for the reason JW mentions – but there is, or at least 
used sometimes to be, another and rather odd one related to EMC filters = if 
these don’t have L-N bleeder resistors and are fitted between the switch and 
the plug there can be stored energy in the caps after the plug is removed from 
the socket with the switch set to OFF (“O”)! Not enough to give you more than a 
mild electric shock, but still enough to make you “jump” and let go of  the 
appliance – not a good idea if it is somewhat heavy and then falls on your foot 
:D (not a myth – it HAS happened, and with painful consequences!)
 
Same thing can happen if the mains cord set is removable and you then happen to 
touch the pins of the male appliance connector on the appliance!
 
John E Allen 
W. London, UK
 
 
From: John Woodgate [mailto:jmw1...@btinternet.com] 
Sent: 28 January 2017 16:32
To: EMC-PSTC@LISTSERV.IEEE.ORG <mailto:EMC-PSTC@LISTSERV.IEEE.ORG> 
Subject: Re: [PSES] Double Pole Mains Switches, Cord Connected Products
 
ALL European 2-pin 6 A plugs are reversible, and 3-contact plugs used on the 
Continent are reversible (there are two kinds, one with 2 power pins and 
side-contact for earth (called 'Schuko')  and one with a third pin for earth).
 
The standards you cite are written so that the product is safe, whichever way 
round the plug is inserted. You do not need a double-pole switch; in fact that 
can be a disadvantage, as it brings the two power conductors close together in 
an assembly with mechanical movement. A short-circuit at some stage in the life 
of the device is not improbable. Also, the insulation can fail, usually with 
smoke and small-scale flame, accompanied by a loud noise.
 
With best wishes DESIGN IT IN! OOO – Own Opinions Only
 <http://www.jmwa.demon.co.uk/> www.jmwa.demon.co.uk J M Woodgate and 
Associates Rayleigh England
 
Sylvae in aeternum manent.
 
From: Mike Sherman ----- Original Message ----- [mailto:msherma...@comcast.net] 
Sent: Saturday, January 28, 2017 4:17 PM
To: EMC-PSTC@LISTSERV.IEEE.ORG <mailto:EMC-PSTC@LISTSERV.IEEE.ORG> 
Subject: [PSES] Double Pole Mains Switches, Cord Connected Products
 
Because of the lack of polarization on many 2 pin European plugs, I have always 
recommended double pole mains switches on cord connected products for the EU 
market. However, I am not finding support for this in standards such as 
60335-1, 60601-1 or 62368-1.
 
Your thoughts will be appreciated, oh experienced group, on:
--safety issue involved
--standards that do require double pole (sometimes referred to as "all-pole") 
mains switches.
 
Mike Sherman
Graco Inc.
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