On 08/04/2021 20:33, Roger Hayter wrote:
On 7 Apr 2021 at 21:42:19 BST, "ARW" wrote:

Am I correct in saying that it does not matter if there is a LN reversal
on the input?

It will always have a correct +/- DC voltage.

Yes, but obviously with an earthed public supply a full wave rectifier
implies that neither + or _ terminal are anywhere near earth DC potential (and
approx equally distant from it). Of course, as the live input is at the same
*average* potential as neutral it is not going to make a difference to the DC
output level which way round you connect the supply.



It also depends on where the protective devices are and where there L-N
reversal is....

If the protective device is in the 13A plug on in the consumer unit
before where the L-N reversal happens then no practical safety issue as
its the L that gets switched off and in a PME earthed house, N will be
close to the same potential as the CPC.

However, if the L-N reversal is BEFORE the protective device, then the N
gets cut anbd you still have a Live L with a potential od 220 V AC RMS
relative to the CPC......