I'm not sure exactly which API you are using, but I'm guessing your confusing stems from the fact that there are indeed two different ways of requesting a resource such a ncpus from PBS:
(name="Resource_List", resource="select", value="1:ncpus=1")
(name="Resource_List", resource="ncpus", value="1")
both sound correct to me. There are some nuances with using select, I'd recommend that you go through the documentation to get more info about it.