Checkline DT-725 - Manual (Page 2)

– 2 –
1.0 I NTRODUCTION
The Check•Line® DT-721(AC-powered) and DT725 (battery powered) Digital
Stroboscopes are highly stable, industrial-quality instruments for non-contact
RPM measurement as well as for inspecting and observing moving parts
by “freezing” or “slowing down” the action.
2.0 OVERVIEW
2.1 Control Panel
Setter: The setter changes the flash
rate. Tune CW to increase the rate,
turn CCW to decrease the ratee.
x2 Switch; Pressing “x2” will double and
display the flashing rate.
1/2 Switch: Pressing the “1/2” will divide
flashing rate by two and display it.
Plus (+) Switch: When object appears to
be standing still, pressing “+” will give the
illusion that the object is moving towards the
opposite direction of rotation. This action
increases the rate slightly (phase shift) and is
used to place the object in desired position.
Minus (–) Switch: When object appears to
be standing still, pressing “–” will give the
illusion that the object is moving towards the
rotating direction. This action decreases the
rate slightly (phase shif) and is used for the
same reason as above.
Input and Output Connectors:
Phonejack (3.5 mm)
Tip: Signal
Sleeve: GND
Power switch with lock option
Power cord (DT-721 only, not shown)
2.2 Kit Option
A “Kit” option is offered which also
includes a carrying case and spare
flash tube at minimal additional cost.
Setter
Input &
Output
Connectors
– 7 –
7.0 F LASH T UBE R EPLACEMENT
When FPM reading is displayed but unit is not flashing, the flash tube may need
to be replaced.The procedure is as follows:
1. Unplug line cord from power line (DT-721). Turn power switch OFF.
IMPORTANT: Wait a few minutes until stroboscope is cool before replacing
flash tube.
2. Remove protective window by removing the
four (4) screws on the face of the instrument.
3. Use a rag and pull the tube out of its socket
by rocking it slightly back and forth.
IMPORTANT: Do not use bare hands to remove
the tube, it may break and cause injury.
4. Insert new tube using the technique mentioned
above. Make sure that the tube is placed vertically
in the socket (see diagram below) otherwise it will
touch the reflector. Tube should be set symetrically
within the neck of the reflector.
5. Replace the protective window.