Vutec makes a great screen.
They have 2 relay boxes
01-R12VU 12Volts
01- R515V 5-15 Volts
Vutec's website has all the answers to your questions.
[Link: vutec.com]See limit switch instructions below.
They have different procedures for different screens.
Double check their website before proceeding.
CHANGING THE LOWER LIMIT
Á Raising the lower limit.
1 - Send the screen down to its lower limit.
2 - Determine the number of turns required to raise the screen past the desired lower limit.
3 - Turn the white hex socket counter-clockwise the number of turns determined in step 2.
4 - Send the screen up past the desired lower limit and stop. Send the screen back down. The screen should
stop above the desired lower limit. If it is not, repeat steps 2 and 3.
5 - The lower limit of the screen should be above the desired lower limit for this step. See Part B of Lowering
the Lower Limit.
 Lowering the lower limit.
1 - Run the screen down to its lower limit.
Warning: Stop - The following steps do not apply to Tab-tensioned screen.
2 - Turn ON the screen down direction switch. Turn the white hex socket clockwise; the screen will advance
downward as each turn is made. Stop when the screen is at the desired lower limit.
3 - Send the screen up and down to check the lower limit setting. Repeat Parts A and B as necessary.
