The Reagan administration's proposals to tie federal worker pay raises and layoff protections to performance ratings got a cool reception yesterday from a Senate panel, whose Republican chairman suggested the new personnel changes "may be too much too soon."

Testifying before the Senate Subcommittee on Civil Service, Post Office and General Services, Donald Devine, director of the Office of Personnel Management, said the proposals were intended to reward and keep federal workers on the job based upon performance, not just seniority.

"It makes excellent management sense," Devine said, to link federal pay to job performance appraisals and to give greater weight to performance in reductions-in-force (RIF) situations.

The Reagan administration wants to eliminate what Devine calls the automatic nature of within-grade pay increases for most white collar federal employes and require instead that an employe's performance has been "fully successful" or better in granting raises. In RIF situations, the administration wants to consider performance ahead of seniority when deciding the so-called "retention rights" of employes.

Sens. Ted Stevens (R-Alaska), subcommittee chairman, Paul S. Trible Jr. (R-Va.), who sat in on the hearing though he is not a committee member, and Sen. Jeff Bingaman (D-N.M.) all argued, however, that the administration should hold off on the changes until their impact can be explored.

"Increasing reliance on the performance appraisal system to provide criteria for various personnel decisions, including promotions and RIFs, needs close examination," said Stevens, who noted there has already been criticism of the performance appraisals conducted under the 1978 Civil Service Reform Act.

Trible said the proposed personnel revisions, published last month in the Federal Register, "promise sweeping and suspect changes" and are being sought "on the heels of other recent pay and benefits actions and proposals all adversely affecting the federal workforce."

Stevens said he was especially concerned that career employes with five years of "outstanding" ratings might be RIFfed on the basis of a lower but more current rating handed down by management, wiping out years of good ratings. Trible pointed out that under the administration proposal a veteran with a minimally successful rating would rank higher than a non-veteran, longtime employe appraised as outstanding. Veterans have long been given special preference ahead of both seniority and performance in RIF situations.

"That does seem to run counter to your arguments for increased productivity," Trible said.

Devine conceded the likelihood of such occurrences. He said the administration might be making some changes following a 60-day period provided for public comment.

"But we've made the judgment that the benefits vastly outweigh any possible problem," Devine said.