Jump to content

As of July 17, 2015, the LabJack forums here at forums.labjack.com are shut down. New registrations, topics, and replies are disabled. All forums are in a read-only state for archive purposes.

Please visit our current forums at labjack.com/forums to view and make new posts. To post on the current forums, use your labjack.com login account. Your old LabJack forums login credentials have been retired. There are no longer separate logins for labjack.com and LabJack forums.


Photo

solid state relay 3-32VDC with U3LV


  • Please log in to reply
8 replies to this topic

#1 moeller

moeller
  • Members
  • 8 posts

Posted 22 January 2013 - 04:50 AM

Hi, I just received my labjack equipment yesterday, and I've already run into problems. I'm a newbie with programming, so I guess it's a simple question. I thought I could control my solid state relays (3-32VDC) with my digital outputs on my U3LV. But when i measure the voltage with the relay connected it only shows 2.0V. Am I doing something wrong or is it simply not possible? best regards, moeller

#2 LabJack Support

LabJack Support
  • Admin
  • 8677 posts

Posted 22 January 2013 - 07:49 AM

You can usually control SSRs with the digital I/O. Are you following the details here:

http://labjack.com/s...s-guide/2.8.1.4

Make sure you are connecting in the sinking configuration, and changing the line between output-low (SSR on) and input (SSR off).

When you measure 2.0 volts, is that across the +/- inputs of the SSR, or perhaps from some point versus GND? Which of the 3 states (input, output-high, output-low) is the digital I/O set to?

What is the control input resistance of your SSR?

#3 moeller

moeller
  • Members
  • 8 posts

Posted 22 January 2013 - 08:18 AM

thank you for your reply. I found the answer though the link. I mistake was that I had connected the DO to GND instead of VS.

#4 moeller

moeller
  • Members
  • 8 posts

Posted 22 January 2013 - 09:33 AM

You can usually control SSRs with the digital I/O. Are you following the details here:

http://labjack.com/s...s-guide/2.8.1.4

Make sure you are connecting in the sinking configuration, and changing the line between output-low (SSR on) and input (SSR off).

When you measure 2.0 volts, is that across the +/- inputs of the SSR, or perhaps from some point versus GND? Which of the 3 states (input, output-high, output-low) is the digital I/O set to?

What is the control input resistance of your SSR?


Ups, I was too fast. The SSR is still not working. If I follow the instructions from the link and uses DI and DO-low I get the voltage of 1,2V(DI) and 2,64V(DO-low). this is measured on the SSR +/- inputs. The SSR needs an input from 3-32VDC.

In the description it says that I should measure 3,7V.

Any suggestions?

#5 LabJack Support

LabJack Support
  • Admin
  • 8677 posts

Posted 22 January 2013 - 12:59 PM

What SSR are you using? Please provide a link to electrical specs for the SSR. Are using an FIO or EIO/CIO? Measuring 1.2V across the SSR control inputs when the line is set to input does not make sense for any SSR. Confirm this by measuring +control to GND (should be 5V) and -control to GND (should be 3.8V if you are dropping 1.2V across the SSR).

#6 moeller

moeller
  • Members
  • 8 posts

Posted 23 January 2013 - 09:15 AM

What SSR are you using? Please provide a link to electrical specs for the SSR.

Are using an FIO or EIO/CIO?

Measuring 1.2V across the SSR control inputs when the line is set to input does not make sense for any SSR. Confirm this by measuring +control to GND (should be 5V) and -control to GND (should be 3.8V if you are dropping 1.2V across the SSR).


I don't have any electrical specs on the relay, but I have attached a picture of it.

I am using FIO4.

When I set the line to input the voltage from +control to GND is 5V and from -control to GND 3,8V.

Attached Thumbnails

  • foto.JPG


#7 LabJack Support

LabJack Support
  • Admin
  • 8677 posts

Posted 23 January 2013 - 10:34 AM

Without more specs about the input circuit we can only guess what might be going on. To just try to get it working, I suggest you try using an EIO or CIO line, rather than an FIO, as they have lower source resistance. The other thing you can try is using a DAC line. Use a sourcing connection to connect DAC0 to +control and GND to -control. Set DAC0 to 5.0V to turn the SSR on and 0.0V to turn the SSR off.

#8 moeller

moeller
  • Members
  • 8 posts

Posted 23 January 2013 - 11:43 AM

Without more specs about the input circuit we can only guess what might be going on. To just try to get it working, I suggest you try using an EIO or CIO line, rather than an FIO, as they have lower source resistance.

The other thing you can try is using a DAC line. Use a sourcing connection to connect DAC0 to +control and GND to -control. Set DAC0 to 5.0V to turn the SSR on and 0.0V to turn the SSR off.



I works fine when I'm using the DAC line, but I need to control more than to SSR and the U3 only have 2 DAC lines.

I will try using an EIO or CIO line tomorrow to see if that fixes the problem.

The relays is suppose to switch off a 100W heating element than uses 230V.

best regards,

Moeller

#9 LabJack Support

LabJack Support
  • Admin
  • 8677 posts

Posted 23 January 2013 - 01:38 PM

Other solutions are to use a different SSR (we often recommend the Jameco 176719 for 24-280 VAC) or to use the LJTick-RelayDriver to drive your CKELE relay:

http://labjack.com/s...river/datasheet


0 user(s) are reading this topic

0 members, 0 guests, 0 anonymous users