Give us a bit more details about what you want to achieve?
Are we talking about premise led strips or your own custom made stuff
Hi,i would look at the possibility of using a 4.5v transformer,and paralleling the feeds. This would mean if one blew,you would still have the other 5,and it simplifies fault finding.
You may be able to do this,using an old phone charger,what is the application? (Just in case it's underwater pond lights...)
Reply to the thread, titled "Transformer to out put 27 volts" which is posted in Lighting Forum on Electricians Forums.