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1.2 Brightness
GLOSSARY:
LED – Light Emitting Diode
msec – millisecond = 1/1,000 of a second
µsec – microsecond = 1/1,000,000 of a second
° = degree. One rotation = 360°
The strobe’s brightness depends on how wide the LED flash pulse is;
the wider the pulse, the brighter the visual output from the LEDs. Since
the strobe is primarily used on reciprocating or rotating targets there is
a downside to the wider flashes.All strobes work by giving short bursts
of light (the pulse width) at a rapid repetition rate (the flash rate).
Strobesrelyonthe persistence of the human eye(theabilitytoremember
and image) and its response to bright light to give an apparent stop
motion image. Imagine a shaft rotating at 6000 RPM or one rotation
every 1/100 of a second (10 msec). If the strobe flashes once every 10
msec for a brief moment, the user sees the flash at the same spot in the
rotation of the shaft and the persistence of the eye remembers this until
the next flash making the shaft appeared to be stopped.As the target is
rotating there is some movement evident during the strobe flash. The
longer the flash duration, the more obvious the rotation is and this
increases the blur.
This blur can be calculated – if the shaft takes 10 msec to complete one
revolution and the strobe flash duration is 100 µsec (1/100 of a
millisecond), the shaft will turn:
(flash duration/time per rotation) x 360°, which is (.0001/.01) x 360 = 3.6°.
So you will see the shaft move 3.6°.As the flash pulse widens you will
see greater degrees of rotation which results in more blur and a brighter
perceived illumination (the LEDs are on longer so the average light the
eyes see is greater). The trade-off is blur versus brightness. One also has
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5.1 Low Battery Indication
When the batteries are charged, there will be no battery icon indication.
When the batteries are low, the Low Battery icon will blink in the
display. The strobe may still be used for a short time.
Low Battery Icon = Outline blinking (very little time left)
The strobe has a protection feature that prevents the strobe from
operating if the battery voltage is too low. This condition is indicated
by no flash and the display shows “LO BAT”. At this time the
batteries must be recharged. Remember to release the trigger switch.
5.2 Charging the Batteries
The unit may be recharged at any time. You do not need to wait until the
low battery condition is indicated.
To charge the strobe with the recharger:
1. Release the trigger so the strobe is off.
2. Plug the recharger cable into the recharger socket (located below
the display panel behind the handle).
3. Plug the recharger into anAC mains wall outlet (115/230 Vac).
CAUTION: Use of rechargers other than the one supplied
(PSC-2UfortheDBL andPSC-PBXUforthePBL)will
damage the stroboscope and void the warranty.
When the recharger plug is inserted into the recharger jack, the strobe
will go into the Charging Mode. Make sure the trigger switch is not
depressed. The DBL strobe will not do anything else when charging
(e.g. it will not flash and the buttons have no function).
When charging, the strobe will indicate CHRGE in the bottom of the
display. The recharger will fast charge the batteries for about 4-5 hours
and then trickle charge the batteries.
