The three companies ranked the lowest by Montgomery County's cable television consultant in the quest for the county's coveted $100 million franchise are calling the classifications inaccurate, unfair and simplistic.

The disputed report by Carl Pilnick, the county's cable consultant, concluded that four of the eight firms seeking the franchise were equally qualified. It rated Tribune-United Cable of Montgomery first, followed closely by Montgomery Cable Communications/Times Mirror Cable Television of Maryland, Tele-Mont Communications, and Viacom Cablevision of Maryland.

Cablevision of Montgomery County, which finished seventh in Pilnick's rankings, charged that "there is hardly a section of the evaluation of the applications . . . that is accurate, balanced and fair." It said two firms rated as equally acceptable, MCCI/Times Mirror and Tele-Mont, should have been disqualified from the ratings for allegedly underestimating their construction costs.

Warner Amex Cable Communications Company, which finished sixth, charged that Pilnick's report contained "gross factual errors" and was simplistic when he suggested that the firm with the most subscribers get the highest rating for general experience.

"By this reasoning, if Company A bought 35 cable systems today, it would be a more experienced operator than Company B which has been operating 10 cable systems for 20 years," said a letter from Christy Carpenter, project coordinator for Warner Amex.

After the April 29 consultant's report, each cable company was given 15 days to respond to Pilnick's report. The responses are the last chance to influence the consultant. As one cable firm official put it, it is a time when "the top firms go after each other and the bottom firms go after the consultant."

Arthur Barber, whose Montgomery Community Cablevision Inc. finished last in the ratings, took both Pilnick and the county officials to task for what he called "telling the county that the companies making the greatest investments have made the best proposals . . . by default."

First County Cable, the fifth ranked firm, took a far less critical stance in its report, but said that the "stigma of a 'significant difference' will be placed on second group applications" and "for all intents and purposes, eliminate them from further meaningful comparisons."

Each of the four top ranked firms offered no criticisms of the county's selection process but suggested their scores should be raised and those of their competitors lowered.

Pilnick will now have 15 days to respond to each of the firm's reports and may make changes in his rankings, although few are expected. The firms will give hour-long presentations at public hearings beginning Monday. So far, Pilnick has been paid $47,000 for his services to the county.