TSI Instruments DustTrak 8520, Operation And Service Manual, Page: 27 / 89

Operation 17

and

Keys
The two arrow keys are used to adjust readings when calibrating the
D
UST
T
RAK
monitor and for adjusting the time and date for the internal real-
time clock.
CALIBRATE Key
Use the
CALIBRATE
key to put the D
UST
T
RAK
monitor into calibration
mode. See Chapter 4, “ Maintenance ” for details on how to calibrate.
Display/Keypad Lockout Switch
Recording data over extended time periods often requires leaving the
D
UST
T
RAK
monitor unattended. To reduce the risk of having an
unauthorized person either intentionally or inadvertently interrupt the
measurements, you can lock the display and keypad.
The lockout switch is on the backside of the D
UST
T
RAK
monitor between the
data port and the external power socket. It is a small slide switch and is
recessed so that a pointed instrument must be used to move it.
With the switch in the right side position (nearest the power socket), all
keypad and display functions will work normally. With the switch in the left
side position (closest to the data port), the display and keypad will go into
lockout mode. There are two ways to use the lockout switch. You can lock
the keypad after recording starts, or you can put the switch into the lockout
position prior to when recording starts. If you select the second method, you
will be able to operate all functions normally
until the SAMPLE key is
pressed in one of the LOG modes. At that time the keypad automatically
locks. When the display and keypad are locked, the display shows the words
“
RECORDING LOG X

” where “ X ” is the current LOG mode number.
Remote Sampling
The D
UST
T
RAK
Aerosol Monitor can be used for remote sampling by
attaching a length of tubing to the inlet. For example, it can be set up for a
test and hidden away where only the sample tubing extends into the area to
be monitored. A 4-foot length of tubing is included with the D
UST
T
RAK
monitor for remote sampling purposes.
Note: Using a sampling tube longer than 4 feet is not recommended
because particle transport losses in the tube may adversely affect
the measurement. Also, do not use Teflon or silicone tubing
because they can cause significant transport losses. Tygon
®
tubing
is a good choice, as is metal tubing if it is grounded to dissipate
static charges.
®
Tygon is a registered trademark of Norton company.