Epson LT-286 - Manual (Page 144)

Write, Read Check
This test checks the ability of the selected disk drive to read and
write data from a diskette. The test writes to and reads from each
track on the diskette, starting at the center. Select option 3 from
the menu to start this test.
This destroys all data on the diskette in the selected drive,
If you are testing drive A, be sure to remove your Reference
diskette from the drive and replace it with a blank, formatted
diskette.
The program displays the current track number as each track is
tested.
Speed Check
This test checks the revolution speed of the diskette drive. Select
option 4 from the menu to start this test. You see a message similar
to this:
The disk rotation speed should be more
than 294.0 rpm and less than 306.0 rpm.
The computer spins the diskette for a few seconds, then displays a
message like this:
The disk rotation speed is now 300.8 rpm.
The rotation speed of a 3 1/2-inch diskette should be 300.0 rpm,
The rotation speed of a 5 1/4-inch diskette should be 360.0 rpm.
This check permits a tolerance of plus or minus two percent,
The diskette continues to spin, and the display is updated every few
seconds. To stop the test, press any key; the menu reappears.
Performing System
Diagnostics D-19