Express dimming issue

[windmill]

Hi.  I'm using Vixen with USB Pixelnet Dongle V2, SS hub, and Express V5.  Channels 1 to 384 for SS and channels 385 to 400 for Express.
For some reason I'm not getting a smooth dimming with the Express.  I'm using incandescent lights on Express.  I tried programming the Express with different curves, but no change.  When I test an Express channel, The light brightens smoothly from step 1 to 246.  At 247 it jumps to full brightness.  I have the Pixelnet plugin set for channels 1 to 400.  Do I need to use a DMX plugin for channels 385 to 400?
Thanks.

[rrowan]

I would check the soldering around the H11A chip and resistors below the transformer and the default curve should work just fine with your lights.

Rick R.

[caretaker]

If you plan on expanding you display you might want to reconsider and reserve 1-512 for DMX and 513-16384 for pixels

[windmill]

Thanks caretaker.  I was thinking about rearranging the channels as well.

Rrowan, it does this on all Express channels.  I can see the LEDs jump in brightness as well.  The strange thing is when I configured the LE, I entered to start at channel 385.  When it programmed, the display showed 353.  So, I entered the start channel at 357 and now the display shows 385.  It's been awhile since I first programmed the unit, but I don't remember it doing that.  I scoped the output and the TRIAC is phasing correctly.  It does not seem the unit is translating the data correctly.  From step 0 to 246 the output voltage is 0 to 62V.  At step 247 to 255, the voltage is 120V.

[rrowan]

Since its all of the channels try swapping out the rs-485 chips


Sent from my iPhone using Tapatalk

[rm357]

By LEDs, I assume you are talking pixels not controlled by the LE.

If everything is doing it, you need to look upstream... Find the common denominator.

Try using the lynx deck software to see if you get smooth fading.

Sounds like something is corrupting the data when you get above a data value of 247...

[caretaker]

If this is only happening to one Express the reflash the PIC there could be corruption of the PIC software.  If it is happening to multiple Expresses then RM suggested try using the LYNX DMX deck if you have a USB dongle and see if the problem remains.