© National Instruments
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NI 17xx Smart Camera User Manual
current. The duty cycle is the ratio of the strobe duration to the frame period, expressed as a
percentage. Refer to the
Maximum Frame Rate
section of Chapter 5,
Image Acquisition
, for
more information about the frame period.
By default, you can set the exposure time to any setting within the range supported by your smart
camera. However, if the smart camera is configured to use the Direct Drive lighting controller
in strobed mode, care must be taken to ensure that the resulting strobe duty cycle and strobe
duration do not violate the limits of the Direct Drive lighting controller or the limits of the light.
For your convenience, the software calculates the resulting strobe duration and duty cycle for
your configured frame rate and exposure time. It then compares them to the limits of the Direct
Drive lighting controller and the limits specified in the associated lighting file. Refer to the
Lighting Files
section of this chapter or the
Maximum Frame Rate
section of Chapter 5,
Image
Acquisition
, for more information.
If the requested exposure time violates the limits of the Direct Drive lighting controller or the
limits for your light as specified in the associated lighting file, the smart camera can use the
requested exposure time, but requires the configured current to be at or below the maximum
continuous
current.
Caution
If you are using the 5 V strobe output or the 24 V strobe output, the
software does not impose any limits on the duration or the duty cycle of the strobe
output. You must ensure that your requested exposure time and the frame rate result
in duration and duty cycle that do not violate the limits of the external controller
and/or light(s). Refer to the
Maximum Frame Rate
section of Chapter 5,
Image
Acquisition
, for more information.
Lighting Files
A lighting file is a text file that contains information about a light, such as the type and color of
the light, maximum current limit, and maximum strobe duty cycle. Lighting files have the
extension
.ild
. MAX and Vision Builder AI use lighting files to ensure that the current limits
and duty cycle of your light are not exceeded when the light is used with the Direct Drive lighting
controller. Lighting files exist in four levels of certification:
•
Digitally Signed by National Instruments
—The information contained within the
lighting file has been verified as correct and safe by National Instruments. Contact National
Instruments for support regarding this lighting data file or the light to which it refers.
•
Digitally Signed by a Third-Party Company
—The information contained within the
lighting file has been verified as correct and safe by the specified third-party company.
Contact the third-party company for support regarding this lighting data file or the light to
which it refers.
