Spiral
®
SST and STT Prewire Installation Manual
Spiral
®
SST and STT Prewire Installation Manual
■
1072124-0
■
Rev 03
■
01/22
32
How to adjust the secondary drive belt
WARNING
Do not perform this procedure
until the power disconnect is in
the OFF position and a lockout/tagout is complete.
Contact with high-voltage wires, or the door being activated
unexpectedly,
can cause death or serious injury.
1
2
Loosen
the top front nut on the baseplate pulley assembly until there is noticeable slack in the secondary
drive belt.
▪
You will need to
loosen
the screws and
move
the CAN bracket out of the way to access the pulley assembly.
▪
It should not be necessary to remove the pulley assembly from the mounting bolt.
Laser level
Always adjust the belt to
lower
the side of the door
panel that is
higher.
17mm
13mm
3
In the head assembly,
“jump” the secondary drive belt
one notch in the pulley.
Adjust the belt
one tooth at a time,
then recheck level.
4
Level
the door panel again.
If the door panel is not level,
repeat these steps and retest.
If the door panel is level,
reset the tension on the belt.
5
To reset the tension
on the belt:
1: Tighten
the top front nut to increase the tension.
2: Press
the front and rear legs of the belt together to test tension.
3: Adjust
the height of the top nut as needed to reach the correct tension.
6
Reinstall
the CAN bracket.
Push up
slack to create
a “wave” in the belt and
hold it against the pulley.
Keep
lower hand
a safe
distance
from pulley
Press
belt up and in
until teeth drop into the
next notch on pulley.
Push
”wave” around
top of pulley and
down the other side.
12"
Laser level
17mm