Checkline PK2X - Manual (Page 11)

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9.0 REPLACING THE FLASH TUBE
Step 1. Remove the front bezel screw
located on the underside of the
front bezel.
Step 3. Firmly grasp the spent flash
tube and pull it straight out.
Step 4. Using a lint and oil-free tissue, insert
a new flash tube into the socket.
NOTE: Yellow colored edge of the
connector should face up
Slide the front bezel over the new tube
and rehinge it at the top. Rotate the
bezel back towards the bottom of the
case and reinsert the front bezel screw.
Step 2. Swing the bezel upwards and
outward. Take care not to break
the old flash tube. Ensure that the
bezel hooks on the top edge are
released. Remove the bezel.
WARNING:
Make sure that the
flash tube is correctly
installed in the sock-
et. If it is crooked,
the light output of
the reflector is
reduced. CAUTION :
Use only PK2X Flash
Tube with the PK2X
Pocket Strobe.
The PK1 or PK2 Flash
Tube is not compatible
with the PK2X
instrument.
incorrect
NOTE: As a safety precaution, the unit will not flash unless the bezel is in place. If
the bezel is not secured properly, an emergency message “E1” will be shown in the
display. Refer to page 12 for additional information.
PK2X Flash Tube
PK2 Flash Tube
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12.0 SLOWING DOWN MOTION
As discussed, the primary use of the Pocket-Strobe is to slow down or “freeze”
the apparent motion of moving objects. This allows you to analyze their
run-time performances safely and easily.
To make an object appear to move in slow motion, you need to strobe it at a rate
slightly above or slightly below its actual speed (or any harmonic of its speed as
discussed below). Simply use the COARSE/FINE ADJUSTMENT knob until you
achieve the desired apparent movement.
Helpful Hints:
The speed at which the object appears to move can be determined by subtracting the
flash rate from the object’s actual rate.
Example: If an object is rotating at 1,000 RPM and you strobe it at a rate of
1,005 flashes per minute (FPM), the object will appear to be moving
at a rate of 5 RPM.
Speed = Actual Rate minus Flash Rate
= 1,000 –1,005 = 5
= 5 RPM
The direction (clockwise vs. counterclockwise or forward vs. backward) at which the
object appears to move is determined by the flash rate, the object’s actual direction of
movement and the orientation of the stroboscopic beam to the object.
Example: Assume you wish to visibly slow down the movement of a fan which is
rotating clockwise at 1,000 RPM.
Case 1: If you stand in front of it and strobe it at a rate of 1,005 flashes per
minute (FPM), the object will appear to be moving at a rate of 5 RPM
in a counterclockwise direction.
Case 2: If you stand in front of it and strobe it at a rate of 995 FPM, it will
appear to move at a rate of 5 RPM in a clockwise direction.
Case 3: If you stand behind it and strobe it at a rate of 1,005 FPM, it will appear
to move in a clockwise direction at a rate of 5 RPM.
Case 4: If you stand behind it and strobe it at a rate of 995 FPM, it will appear
to move in a counterclockwise direction at a rate of 5 RPM.
NOTE: Typically, stroboscopes are brightest (and can therefore illuminate an
object the best) when the flash rate is between 2,000 and 6,000 FPM.
Often, you can still make an object appear to be frozen or moving in
slow motion within this range because of the effects of harmonics.
This principle is explained section 13.