Fall and winter hours for the D.C. Public Library begin Monday and a change in the overdue fine system goes into effect Sept. 15.

The main Martin Luther King Memorial Library, 901 G St. NW, will be open from 9 a.m. to 9 p.m. Mondays through Thursdays and 9 a.m. to 5:30 p.m. Fridays and Saturdays. The Children's Room will be open 9 a.m. to 6 p.m. Mondays through Thursdays and 9 a.m. to 5:30 p.m. Fridays and Saturdays. The Library for the Blind and Physically Handicapped, in Room 215, will be open weekdays from 9 a.m. to 5:30 p.m.

New hours at other libraries are:

Fort Davis, Chevy Chase, Woodridge and Georgetown regional branch libraries -- 9 a.m. to 9 p.m. Mondays through Thursdays; 9:30 a.m. to 5:30 p.m. Fridays and Saturdays.

Capitol View, Cleveland Park, Northeast, Petworth, Southwest, Tenley-Friendship, Watha T. Danial and West End branches -- 1 to 9 p.m. Mondays and Wednesdays; 9:30 a.m. to 5:30 p.m. Tuesdays, Fridays and Saturdays; closed Thursdays.

Anacostia, Benning, Mount Pleasant, Palisades, Southeast, Takoma Park and Washington Highlands branches -- 1 to . p.m. Tuesdays and Thursdays; 9:30 a.m. to 5:30 p.m. Mondays, Wednesdays and Saturdays; closed Fridays.

Garnet C. Wilkinson branch library (second floor of Garnet C. Wilkinson Elementary School) -- 9:30 a.m. to 5:30 p.m. Mondays through Fridays.

Langston, R. L. Christian, Sursum Corda and Trinidad community libraries and Deanwood, Parklands, and Barry Farms library kiosks -- 9:30 a.m. to 5:30 p.m. Mondays, Tuesdays, Thursdays and Fridays; 1:30 to 5:30 p.m. Wednesdays.

Overdue fines will be five cents per day for all books beginning Sept. 15. The public library discontinued overdue fines for children's books in January 1968. The fines are being put back into effect because the percentage of children's books returned, late or not at all has increased.

The maximum overdue fine for adult books will be $3, an increase of $1, and the maximum fine for children's books will be $2. The same change will be made for phonograph records. Maximum fines for overdue paperback books and periodicals will also increase from 25 cents for adults and free for children to $1 per item.

Fines for overdue posters, prints, picture sets and vertical file materials will be 5 cents per day. The maximum fine for posters, picture sets and vertical file materials will be $1 for adults and juveniles, and the maximum for prints will be $3 for adults and $1 for juveniles.