Telephone repair workers at the Western Electric plant in South Arlington walked off their jobs shortly after 1 p.m. yesterday in a dispute over disciplinary hearings by officials at the plant.

The wildcat strike by about 300 members of the Communications Workers of America Local 2395 occurred after company officials assigned two management supervisors - instead of the customary one - to hear disciplinary cases involving three union members suspended earlier this week.

The plant, one of the largest telephone repair facilities in the country, employs about 600 workers.

Company and union officials said yesterday that under terms of the contract, two supervisors can be assigned to hear disciplinary cases.

As employes milled around the parking lot outside the plant in the rain, local union president Ron McGee stood on a truck and explained that he had called the wildcat strike - an apparent violation of the national contract - after failing to reach a compromise with management officials.

"Assigning two supervisors is an unfair form of job pressure and has never been the practice here," said McGee as small groups of strikers jeered several of their colleagues who re-entered the plant.

McGee told the strikers to report to work today and said he would ask company officials to take no disciplinary action against the strikers, who are subject to three-day suspensions.

In an interview, Western Electric production manager Christopher Dipple said that a decision about suspensions would be announced to the workers today. "Right now we're meeting and trying to get people back to work," he said.

In meetings earlier this week Dipple said he told McGee that two supervisors might be assigned to hear cases involving employes "who have done something threatening or if the grievance involves a sensitive area. I'm not willing to give that right up."