DMX Troubles with AXB-DMX512

Onkelz

Hi all

At a big DMX installation (around 50adresses) we use a AXB-DMX512 for controlling the lights. It works well but from time to time we have the problem that the lights go "ON" automatically. The system is for some seconds totally out of control. It happens not often (around one time every week).

Do somebody knows something about this problem?? We have allready changed the DMX Gateway, but it is the same with the new AXB-DMX512

TurnipTruck

Onkelz wrote: »

Hi all

At a big DMX installation (around 50adresses) we use a AXB-DMX512 for controlling the lights. It works well but from time to time we have the problem that the lights go "ON" automatically. The system is for some seconds totally out of control. It happens not often (around one time every week).

Do somebody knows something about this problem?? We have allready changed the DMX Gateway, but it is the same with the new AXB-DMX512

Are you sure that it is not a problem with the DMX signal circuit? Some dimmers can be set to go to 100% when signal is lost or otherwise unreadable.

roognation

Color Kinetics

I am using the DMX512 to control some color LEDs by Color Kinetics. I don't know if they are related, but there are times when the sending out DMX signals does nothing, but rebooting the DMX512 solves the problem. I wonder if the DMX signal is too hot and overdrives the LED controller to some unknown state...AMX and Color Kinetics blame the other guy.

PhreaK

Have you got the ability to hook up a different controller to your DMX bus? If you haven't got anything there are load of cheap easy to built 232 -> DMX schematics available via google. That will at least let you identity where the fault is taking place.

TurnipTruck

roognation wrote: »

I am using the DMX512 to control some color LEDs by Color Kinetics. I don't know if they are related, but there are times when the sending out DMX signals does nothing, but rebooting the DMX512 solves the problem. I wonder if the DMX signal is too hot and overdrives the LED controller to some unknown state...AMX and Color Kinetics blame the other guy.

Is the end of the DMX line terminated? You should have a 120 ohm resistor across pins 2 and 3 of the DMX out of your last device.

Also, sometimes DMX devices can't keep up with the refresh rate of their controller. In this case, an interbyte delay must be introduced. Not all controllers have this ability though.

roognation

TurnipTruck wrote: »

Is the end of the DMX line terminated? You should have a 120 ohm resistor across pins 2 and 3 of the DMX out of your last device.

Also, sometimes DMX devices can't keep up with the refresh rate of their controller. In this case, an interbyte delay must be introduced. Not all controllers have this ability though.

Oh, that terminator might be it. We have the DMX512 hooked straight up to a CK controller/power supply about 3 feet away, not a lot of devices. And I don't think there is a terminator on there, so I will check next time on-site.

Thx!

harry_aller

DMX lights going white!

Curious if you were able to solve your problem by adding the 120ohm resistor...

We are having similar craziness on a site with about 15 DMX devices. Randomly (and I mean randomly ) some lights will go solid white. We did have a resistor at the end of the chain. Resetting the AXB-DMX512 does help, but only for a little bit.

Other thoughts / suggestions?

Thanks!

nielsy

There is also a option in the AXB-DMX512 to terminate the incoming DMX signal.

I'd some troubles to, and when there where troubles also the RX led was ON.
When only DMX OUT was connected.

It's a jumper on the print to do that.

I don't know if you have the troubles that the RX led in ON ?
It should be only the TX when you have no DMX input connected.

Good luck!

harry_aller

I wondered about that. The RX LED has been turning on from time-to-time. I'll look at the jumpers. Thanks!