The Educational Institute of Scotland has called for an investigation into the management and governance of the college.
Douglas Nicol, 57, branch convener, told the tribunal that he was discriminated against by being demoted from senior lecturer to lecturer.
The tribunal heard that Mr Nicol had been accused of "wilfully disregarding his duties" after he was timetabled to take a group of hospitality students but was found to be dealing with other duties instead.
He was disciplined and demoted from his pound;30,000-a-year post with a pound;3,000 drop in salary.
Ronnie Smith, EIS general secretary, said the college had paid out more than pound;65,000 in tribunal awards and settlements in five years. "That is a very bad track record and we are calling for an investigation," Mr Smith said.
Lorna Smith, core curriculum manager at the college, told the tribunal that her relationship with Mr Nicol was professional but "tense and difficult".
Mr Nicol said he was shocked when he discovered the severity of the disciplinary action.
The tribunal found that Mr Nicol may have been guilty of an error of judgment but said his treatment was "wholly disproportionate". The award included pound;10,000 for injury to his feelings.
"The applicant has lost status as a result of his demotion in circumstances in which on no basis could demotion be justified. He has had over 25 years of service," the tribunal stated.