Automatically shutdown after running mins

Yajun,

The current LightCrafter 4500 has active cooling that is sufficient to keep the system within spec if the total LED currents do not exceed 4.3A.

The problem might lie with the power supply being overload, overheating and shutting down.

Make sure your power supply is able to provide:

• 12V nominal voltage
• 5A nominal current

Best regards,

  Pedro

Hi, Pedro,

We use the recommended power supply (Model: CENB1060A1203F01). It supplies 12V nominal voltage and 5A nominal current. 

We run the projector at Pattern Sequence mode and we just use the Green light for projection. We set the Internal trigger 1000 us, exposure time  750 us and the image load time 1000 us.  For the current setting, when we set 150, it can runs about 2~4 mins. When we increase the current setting, the running time will be shorter. If we set it as 255, it can only run 10 or 15 secs. Do you have any suggestion to make the projector run longer?

Thanks.

We have run several LightCrafter 4500 systems non-stop for several days on temperature chambers up to 50C and not seen an issue. I ran a set of 24 grey code patterns from flash at those settings (current setting of 150) for over an hour and my LightCrafter did not stop. Using the current setting of 255, I ran for over 30 minutes and it did not stop. I am attaching a screen shot of my settings.

Is the fan running during your tests?

Is the LED blinking green while displaying the patterns?

What happens to the LED when the pattern sequence stops?

Could you measure supply voltages while the pattern is running and when the patterns stop to see if they are below spec?

I also noticed that you have set Image load time to 1000us. The longest time the DLPC350 takes to load 24-bit fields of an image from external Flash memory is typically 200 ms. For simple images, the load time might be 8ms. Once an image is loaded from Flash, 24 bit-fields reside in the frame buffer and can be sequenced at higher speeds. Two 24 bit-field display buffers are available in the DLPC350. While one buffer is loaded, the previous buffer is displayed. If the pattern sequence uses more than one image or 24 bit-fields, then the 24 bit-field pattern sequence must be larger than the buffer load time to allow sufficient time to load the next buffer while displaying the current buffer. In summary, if you are using less than 24 bit-fields, this will not be an issue. If you are using more than 24 bit-fields, you need to allow for sufficient time for the next buffer to load.

At worst case 200 ms is required to load the new image into the DLPC350 internal display buffer. You can figure out the time it takes to load an image by using the Image/Firmware tab and looking at the Image Load Time sub-section.

The fan is still running and the LED is also blinking green after the pattern sequence stops. I can still see some week light projecting out from the lens.  I just use one 24 bit image. If i want to project the patterns at 1000 Hz, what should I set for the image load time? I tried 200000 us, but it said the buffer display time is smaller than the buffer load time. 

This seems to be caused by the bitmap image. Make sure the 24-bit image has data in the color bitfield selected (G0-G7, R0-R7, or B0-B7).

For example, in the firmware there is an 8-bit image in Splash 1. You can create a single pattern sequence with any LED, select G0-G7 and 100ms for Internal Trigger, Pattern Exposure, and Image Load time. It will display fine. Selecting R0-R7 or B0-B7 just uses a different portion of the image. Basically we have a set of vertical bars corresponding to a 8-bit greyscale bitmap.

However, Flash index 12 is a 24-bit image with the data only on the blue color. Then using the same settings as above, the pattern sequence will not produce an output since G0-G7 is all zero. You would have to select B0-B7 to see the image. When the DMD is set to zero, you will see a faint light projected since some stray light internally reflected will be outputted by the projector.

Now, Flash index 9 is a 24-bit image with the same data in every color. So selecting G0-G7, R0-R7, or B0-B7 will produce the same image.

You can explore the differences in these images by projecting the Flash index in video mode versus pattern sequence mode.