Looking for a Labview controllable relay or switch

[Joni-Wan]

Hi Guys,

I have a Labview controllable power supply, which does not have the ability to change its polarity. Since I need to do that with Labview, I want to build a circuit with a Labview controllable Relay or even better just a switch to do so. I tried to find something like that, but wasnt succsessful yet. Does someone know a device like that and can help me out?

Thanks in advance.

Joni

[crossrulz]

How do you want to connect to said relay?  PXI?  Digital Output?  LAN?  Serial?

What type of relay?  How much current draw does it need to handle?

[Joni-Wan]

Ah, sorry forgot about that.

Best would be a USB connection.

It should be able to pass a current of up to 8 Ampere.

It only needs to be able to switch beween the two inputs with different polarity.

[crossrulz]

Sounds like you will want a USB DAQ board that has digital outputs on it.  You will then need to develop a circuit to control the DPDT relay.  You will need a buffer circuit to increase the current of the digital lines.  You can find all the parts you need on Digikey.

[Joni-Wan]

Yes I had the same thought. I am using an USB DAQ with output capability for other things, but I was hoping for an easier solution.

[SteveD123]

Well the solution is quite easy. The search term is "Solid State Interface Relay", somethng like a Digikey  277-2384-ND  (Phoenix Contact 2980144). Wire between your digital outout and a power relay. You will need a seperate PSU for the power relay. Use changeover contacts on the power relay to change the polarity of your PSU.