Dear experts I again need your opinion on below issue.

Customer was asked for development of power supply which will be used to supply 
a  server in data centre. Input to power supply is defined as 750VDC. 
Unfortunately no information is available how this DC supply voltage is 
generated and reference to PE. Most probably it will be floating.

Now the problem, what standard to use for such product?

-          Standard IEC 60950-1 which is most often used is limited to 600V 
rated voltage. Does it mean 600VRMS? Is it then allowed to approve also 
products with 600xsqrt(2)=848VDC  rated voltage according IEC 60950-1 or limit 
is also set to 600VDC? Where this limit actually comes from? If you check 
requirements for clearance and creepage distance they go quite higher than 600V.

-          Standard IEC 62477-1 could be appropriate standard however problem 
is that this standard is not worldwide harmonised and therefore no national 
certificates (US/CAN, China) are possible based on report according to this 

-          What other standard would be OK for US/CAN?

I appreciate your feedback.

Best regards,

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