Roland VersaUV LEJ-640 Service Notes page 181

Move the Head Carriage to the right edge of the bed. And
16
check that the space between the UV Lamp and bed is 7mm
to 7.5mm.
If the space between the UV Lamp and bed is not 7mm to
7.5mm, go back to the step 12 and fi x the UV Lamp again.
Enter the Service Mode and perform the following check.
1. [4-13 UV LAMP CHECK]
7mm ～ 7.5mm
3-107