Drive SSR through the AO of USB-6212

[MichailM]

Hi,

Assuming we have a solid state relay (SSR), let's say the DR2260D20V (Datasheet). The control voltage range is 4-32VDC which can be provided by the AO channels in the USB-6212. Minimum input current for on-state of the SSR is 7mA while maximum input current is 15mA. As far as I know, input current is the current that flows through the SSR input when the rated voltage is applied. The input current will varry relative to the input voltage in a non-linear way (the datasheet has the graph). Let's say that if I apply a 5VDC then the input current will be  approximately 10mA. 

My question: The current rating of the AO of the USB-6212 is 2mA. Will it be possible to drive the SSR through the AO and how can I protect the DAQ card (if possible)?

Many thanks!

[santo_13]

SSR datasheet gives you the curve,

If you want to "reliably" turn it ON, at least 4V is required.

Why do you drive the SSR using AO instead of a DO? and the DO can source or sink upto 16mA

Given the IOH is between 8mA and 40mA across 0-55C, you can easily manage the minimum 7mA requirements of your SSR.

[MichailM]

In all honesty, I have never worked with the DOs. Do you by any chance have an example on how to achieve, let's say, a 5VDC output using the DOs?

The application is to use the SSRs to turn on and off the mains that supply two heating elements. Below is the code I was about to use with the AOs.

[santo_13]

It is similar to your code but switched to the DO variant of each of the DAQmx VIs used.

This is a good equivalent example,