NCD R8xPL with Lantronix Ethernet - Relay on time

Hi-

I would like to have very fast time ON control of the relays on this product. Basically, I would like to be able turn a relay on for a programmable amount of time and then off again, rather than just on/off clicks on buttons as supported by the provided GUI. Double clicking the relay from off to on and back off again as fast as I can on my PC yields an on time of about 330 ms. I really would like to program it to be on for as little as 10-30 ms. My application is that the relay is controlling a zoom focus motor, so I need a pretty short duration in order to have a small enough step size so that I can achieve the desired zoom.

So for instance, instead of a button that changes from on to off, I need one that simply turns it on and then off quickly (10-30 ms) with a single click. I’m not sure if something like this is already available, or if its feasible with speed of the HW that is processing the commands on the NCD relay board. I expect it will require a new GUI/app, but would like to know if its possible before having someone dig into how to modify or create the SW to do so.

Thanks!

Hi,

I assume you are probably using the NCD Base Station software right now. If that’s the case then follow these instructions:

  1. Open the Base Station software and connect to the board.
  2. After Base Station is connected you will see the main window where you can open different sections of the software. Click on the Device Configuration button on the left.
  3. Here you will see settings for the board. Look for ProXR Ticks Per Second. I believe the default value will be something like 246. Lower that down to around 50 or so, then click Store Configuration. You may be prompted to click the button to put the board into Configuration mode, if so do that, then click Store Configuration again. What you just did is reconfigure how long the board thinks a second is. That will allow us to use timer commands to turn the relay on for a short duration and back off.
  4. Now back at the main window click on ProXR Enhanced Relay Control Command Set.
  5. Here you have the on/off buttons for the relays. These are more than likely the buttons you were using previously to manually turn the relays on and off. Instead of pressing those click on the Relay Timers button.
  6. You will now see the Relay timer interface window. Set How Many Seconds to 1(leave all other settings as they are) then click Activate Relay Duration Timer. That should pulse the first relay on the board(0 as indicated by the UI in software) for a short duration.

This is how I recommend pulsing relays. We have had reliable pulse durations down to around 50 milliseconds. You may want to put together some custom software to make the interface and use of these timers a bit simpler. Or you could look into N Button Lite from www.serialporttool.com which allows you to create custom buttons that could send relay duration commands.

Please let us know if you have any questions on this.

Thank you,
Travis Elliott

Travis-

Thanks for the info. I’ll give it a try soon. Probably will have more questions…

thanks,
Dave

Hi Travis-

I tried your suggestion, and the pulse duration reduced to about 220 ms. I tired a couple of other things:

  • reduced ticks from 50 to 15 with no change in the results.
  • change the UART delay and Baud Rate to 230KBaud with no change in results.

So I was wondering if you could tell me where all the time is consumed. Sort of a breakdown such as:

  • PC SW/GUI
  • Ethernet
  • Lantronix module processing
  • UART to on board processor time
  • Processor command processing to Relay control

I did not try custom SW yet. Thanks for all your help,

Dave

How are you measuring the on duration to be 220ms? Are you doing it with a scope on the relay contacts? That is the only true way to see the duration the relay is actually on since there are other delays(as you mentioned software to board communication, board processor command processing, board to computer response, etc). If you lower the ticks per second down very low you should see a contact pulse on the relay contacts as low as 50ms.

Hi Travis, yes measuring the pins on the relay directly with a scope in normal trigger mode to capture the pulse.

Thanks,
Dave

By adjusting the ProXR Ticks Per Second setting down you should be able to achieve a much lower pulse duration than 220mS. Are you sure the setting is “sticking” after you set it?