Craftsman 139.53974SRT Owner's Manual page 24

MounUng
a nd Wiring the Safety Sensors
• Slide a I14"-20xi/2' cardagebolthead intothe slot
on bothsensors.Use wing nutsto fastensensorsto
brackets,with lenses pointingtowardeach other
acrossthe door. Be sure the lens is notobstructedby
a bracket extension. See Figure 5.
• Fingertightenthe sensorwingnuts.
• Run the wires from both sensorsto the opener.Use
insulatedstaples to secure wire to wall and ceiling.
• Strip 114" of Insulationfrom eachset ofwires.
Separate white and white/blackwiressufficiently to
connectto the opener terminalscrews: whiteto 2
and white/blackto 3.
Aligning the Safety Sensors
• Plug in the opener.The indicatorlightsin boththe
sendingand receivingeyes willglowsteadilyif wiring
connections and alignmentare correct.
The sandingeye orange indicatorlightwillglow
regardlessof alignmentor obstruction. I f the green
indicator lightin the receiving eye is off, dim,or
flickering(and the invisiblelightbeam pathis not
obstructed),alignmentis required.
Loosenthe sendingeye wing nutand readjust,
aimingdirectly at the receivingeye. Lock in place.
Loosenthe reoeivingeye wingnut and adjustsensor
vertioallyand/orhorizontallyuntilit receivesthe
sender'sbeam. When the green indicator lightglows
steadily,tightenthe wing nut.
Figure 5
114 2OXI/2 ""_
Trouble Shooting the Safety Sensors
1. If the sendingeye indicator l ightdoes not glow
steadilya_erinstallation, checkfor:
• Electricpowerto the opener.
• A shortin thewhiteor white/blackwires. These can
occurat staples,or at screwterminalconnections.
• Incorrectwiringbetweensensorsand opener.
• A brokenwire.
2. Ifthe sendingeye indicator lightglowssteadilybutthe
receivingeye indicator l ight doesn't:
• Check alignment.
• Checkfor a broken wire to the receivingeye.
3. If the receiving eye indicator lightis dim, realigneither
sensor.
NOTE: Whentheinvisible beam path is obstructedor
misalignedwhile thedooris closing, t he door will
reverse. If the dooris alreadyopen, it will not close. The
openerlights v_ll#ash 10 times.(If bulbsare not
installed, 10 dicks canbe heard.) See page 21.
Figure 6
Door Control
sensor
Connections
f
OPENER TERMINAL SCREWS
Sensor Pro_ectio_ Area
23