This article is by all means true, yes, there is (undefined) low-limit on reliably switching low voltages while using high power relays, and you have to put this information into context of what you are trying to do ..
So have a look at your original question .. is 30Vac ok with 30Vdc-250Vac relay?
The answer is that unless you are not talking about a big, big relay rated for kWs of power, all other relays (suitable for your load) will work just fine ..
:wink:
IanP