Battery Safety; Installing Aaa Batteries; Using The Stud Sensor - Craftsman CMHT77620 User Manual

CAUTION:
E
Use personal protective equipment. Always wear eye
protection. Depending on the work conditions, wearing
protective equipment such as a dust mask, non-skid
safety shoes, hard hat, and hearing protection will
reduce the risk of personal injury.
IMPORTANT SAFETY NOTICE
Ensure proper detection of live wires. Always hold the Stud Sensor
CMHT77620/CMHT77621 in the handle area only. Grasp between
fingers and thumb while making contact with your palm (Figure
).
C
NOTE: Static electrical charges that can develop on drywall and
other surfaces will spread the voltage detection area many inches
on each side of the actual electrical wire. To aid in locating the
wire position, scan holding the unit ½" (13mm) away from the
wall surface or place your other hand on the surface approximately
12" (305mm) from the sensor.

Battery Safety

WARNING:
Batteries can explode, or leak, and can cause injury
or fire. To reduce this risk:
• Carefully follow all instructions and warnings on the battery
label and package.
• Always insert batteries correctly with regard to polarity (+ and
–), as marked on the battery and the equipment.
• Do not short battery terminals.
• Do not charge disposable batteries.
• Do not mix old and new batteries. Replace all batteries at the
same time with new batteries of the same brand and type.
• Remove dead batteries immediately and dispose of per local
codes.
• Do not dispose of batteries in fire.
• Keep batteries out of reach of children.
6

Installing AAA Batteries

Load two new AAA batteries in the CMHT77620/CMHT77621 stud
sensor.
1.
On the bottom of the laser, lift up the latch (Figure
to unlock the battery compartment cover.
2.
Move the cover upward (Figure
separates from the stud sensor.
3.
Insert two new, high-quality AAA batteries, making sure to
position the - and + ends of each battery as noted inside the
battery compartment (Figure
4.
Place the cover back on the stud sensor.
• Insert the two pins at the top of the cover into the holes in
the stud sensor (Figure
• Slowly lower the cover and press down until the latch locks
securely on the stud sensor (Figure
5.
Press to test the stud sensor.
• All the LEDs except the green Power
illuminate for a second and then turn off.
• Whenever you press
illuminate to indicate that the batteries are good. If this
LED blinks or does not illuminate, change the batteries.

Using the Stud Sensor

The stud sensor will help you find wood or metal studs, and AC
voltage behind drywall.
• CMHT77620 will work on up to 3/4" (19mm) thick drywall.
• CMHT77621 will work on up to 1.5" (38mm) thick drywall.
• CMHT77620 and CMHT77621 will detect AC voltage through up
to 2" (50.8mm) thick drywall.
• When AC voltage is found, the stud sensor will sound a few
short (alternating) beeps and light the AC LED (Figure
• When the center of a stud is found, the stud sensor will sound
one longer (constant) beep and light the center LED (Figure
).
A 5
• When live AC and the center of a stud are both found, the stud
sensor will sound both the long beep and the short beeps, and
light the center and AC LEDs.
B 1
) and remove it once it
B 2
).
B 3
).
B 4
).
B 5
LED should
, the green Power LED should
A 3
)
).