Starts a job tracking timer. When the operation is grouped under a work order, the work order operation's timer is started instead; it covers every job operation grouped under it.

The user identifier to associate the timer to. If not supplied, will use the user assigned to the api key used for authorization

The job identifier

The item to make identifier

The operation identifier. When the operation is grouped under a work order, the work order operation's timer is started instead and covers every job operation grouped under it