BANGOR — An auto mechanic convicted in the fatal crowbar beating of another man was ordered Wednesday to serve seven years in prison for the killing, which he described as self-defense.

Eight of the victim’s family members, including his widow, made emotional pleas for the maximum penalty of 30 years in prison for Peter Robinson, but a judge suspended half of Robinson’s 14-year sentence.

Robinson, 50, of Bradford, was convicted of manslaughter in the November 2011 death of 71-year-old David Trask, a construction company owner from Hudson. There was bad blood between Robinson and Trask before an altercation turned deadly.

In court, Robinson apologized Wednesday to Trask’s family, saying he understood the gravity of his actions, but he reiterated that he acted in self-defense after Trask attacked him.

Robinson, who owns an automotive garage, said that he grabbed the crowbar from Trask’s hands and beat him with it. He said he thought Trask’s cellphone holder was a gun holster.

CORRECTION: This story was updated on Wednesday, July 17, to correct the spelling of the victim’s name.