Well as an examiner on my mark sheet we have boxes for pass, pass+, commendation, high commendation, honours and distinction.
We use pass as 50-59%, commendation 60-64%, high commendation 65-69%, honours 70-85% and distinction 86% or greater.
Pass+ does not actually have a grading but rather denotes where the examiner feels the candidate deserves a commendation but missed the grading so will tick + and write the percentage.
But it doesn't mean that every candidate who scores 59% will get pass+, it depends on the examiner.
I rarely use it, as it is too confusing.