LabView Relays | LabJack
 
Friday May 29th 2020
Support: LabJack engineers available through email and chat.
Shipping: We are processing and shipping all orders.
Stock: 51 of 56 products are in stock. More details.
Supply Chain: Minor impacts. More details.

LabView Relays

4 posts / 0 new
Last post
dekhissia
dekhissia's picture
LabView Relays
Hello, We recently bought a LabJack T7. We want to control with it 5 relays 24V (DIO outputs). To do this, we have created a LabView program which you will find enclosed. On the other hand we do not know how to control the LabJack DIO outputs under LabView. Any help would be appreciated. thanks in advance.
LabJack Support
LabJack Support's picture
The general process for

The general process for tackling a task like this would be:

1.  See the following app note about controlling relays:

https://labjack.com/support/app-notes/Controlling-Relays

2.  Use the Dashboard in Kipling to control the digital I/O and confirm the relays switch as expected.

3.  Go to the "Digital I/O" section of the T7 datasheet to decide what register or registers you are going to write to control your 5 digital outputs.

https://labjack.com/support/datasheets/t7/digital-io

4.  Lets say you decide to do 5 writes to the bit registers for each DIO.  For example, to set FIO0-FIO3 high and set FIO4 low you decide to write FIO0=1, FIO1=1, FIO2=1, FIO3=1, and  FIO4=0.  You could do that with 5 calls to eWriteName, but it would be more efficient to make 1 call to eWriteNames:

https://labjack.com/support/software/api/ljm/function-reference/ljmewrit...

5.  In the LabVIEW_LJM archive you can look at "LJM_eWriteNames Example.vi":

https://labjack.com/support/software/examples/ljm/labview

We do everything in LabVIEW 7.1 (for maximum compatibility) and don't have newer versions, so can't open your attachments.  If you need us to look at your code attach a screenshot.

https://labjack.com/support/app-notes/screenshots

dekhissia
dekhissia's picture
Hello,
Hello, I have 3 LJTick-RelayDriver to connect to digital outputs of a LabJack T7. Should I wire the 3 VR terminals to the highest load voltage? Or may be just one is enough?
thank's

LabJack Support
LabJack Support's picture
The VR connection is totally

The VR connection is totally optional.  If you don't connect it you just will not have the extra protection provided by the VR clamping.

Any voltages on RA or RB that are greater than VR will be clamped.  So on each LJTRD you want to connect VR to the highest voltage that will be seen on RA or RB on that LJTRD.