The Senate, as expected, refused yesterday to cut off an 11-day filibuster against a bill to revise federal labor laws in the first of a series of expected cloture votes.

The motion to shut off debate failed even to draw a plurality, with only 42 members voting for it and 47 against. It takes 60 votes to invoke cloture.

Majority Leader Robert C. Byrd (D W. Va.) had acknowledge earlier this week that yesterday's attempt probably would fail. He has vowed to continue trying daily, hoping for victory late next week.

Labor Secretary Ray Marshall said yesterday's vote "came as no surprise," adding it would be "a mistake to try to read anything else" into the vote.

However, the National Association of Manufacturers, a leading opponent of the bill, said the vote is a valid measure of the opposition's strength.

The certainly of failure apparently contributed to the law vote in favor of cloture because some members were absent and others used the prediction of defeat as a "free pass" to vote no, a labor spokesman said.

But it provided the first test of sentiment on a bill that has caused senators to be badgered for months by lobbyists and inundated by millions of postcards and letters.

The measure is designed to streamline operations of the National Labor Relations Board and, in general, make it more difficult for employers to block unionizing of their workers.

Even if cloture is invoked, opponents have pledged to tie up the Senate by offering 500 amendments and demanding time-consuming roll-call votes on each - hoping this would persuade sponsors to withdraw the measure.

Sen. Dale Bumpers (D-Ark.),considered a key swing vote, said as the vote began he would vote against cloture for the first time in his four years as a senator. He said obstructionist tactics are "abhorrent" to him but "if cloture is invoked, the bill seems fairly certain to pass in something quite close to the form" in which it reached the floor.

He said he was concerned about the effects of the bill on small business and about "the suspicion that the bill's supporters believe it may help diminish the attraction of the South for new industry."

Just before the vote, Sen. Harrison A. Williams Jr. (D-N.J.) gave the first hint of movement by supporters to winthe needed votes.

He told Sen. John J. Sparkman (D-Ala.) that amendments to make the bill more palatable to nonfilibustering opponents would be introduced before a final cloture vote, so that they could be acted on after debate is limited.

The bill is the product of the first major effort by organized labor to overhaul the National Labor Relations Act since it was passed 44 years ago. Drafted by the White House in concert with top union officials, it sailed through the House late last year by a lopsided margin in somewhat stronger form that the pending Senate measure.

It was only after the House vote that industry, from the blue-chip Business Roundtable to various groups of small business, mounted a massive lobbying campaign to stop the legislation in the Senate - what AFL-CIO President George Meany has called a "holy war" against the union movement.

Organized labor, attempting to match its foes letter-for-letter and horror story-for-horror story, says the measure merely puts teeth in existing labor laws to block antiunion employers of depriving workers of their right to organize and bargain collectively. Business responds that the bill is a desperation move by a shrinking, problem plagued labor movement and says it would aggravate inflation, upset the existing balance between labor and management and drive many small business into the ground.

president Carter, who has had troubles with organized labor on inflation and other issues, has gone all-out in support of the bill, making the vote a test of his clout, as well as labor's, in Congress.

In addition to setting deadlines of 30 to 75 days for holding union representation elections, expanding the National Labor Relations Board from five to seven members and refining its procedures to expedite action, the bill would stiffen penalties for violating existing law.

It would provide time-and-one half back pay for workers illegally discharged for union activities, authorize interim wage increases when employers refuse to bargain on a first contract, and permit the secretary of labor to cancel government contracts with repeated labor law violators. It also would permit unions access to company property to answer employer's antiunion charges in representation campaigns.