maxBooleanClauses in solrconfig.xml is ignored

[Zaccheo Bagnati]

Hi all,
I'm trying to set the maxBooleanClauses parameter in solrconfig.xml to 1024
but I still have "Too many boolean clauses" error even with 513 terms (with
512 terms it works).
I've read in the documentation (
https://cwiki.apache.org/confluence/display/solr/Query+Settings+in+SolrConfig)
the warning that it is a global setting but I have only 1 core so there are
not conflicting definitions. I don't know how to deal with this
I'm using SOLR 5.5.
Thanks
Zaccheo