NI 6008 to control I/O Solid State Relay Omega DCO5-C

Hi NI Community,

I am trying to use my NI 6008 to send a TTL signal for switching 12V DC in a solid state relay (Omega DCO5-C).  This relay is controlling the power to a solenoid valve. 

For the solid state relay, "output modules receive TTL signals from the computer interface, and will switch ac or dc power lines on or off".   The LED light on the backplane light up when 5V is supplied, but I do not get switching of the 12V DC power.  

Can I not send the appropriate TTL signal with my NI 6008?   Is there any way to create the correct signal?  I have read up on TTL signals, but this has been my only lesson.

Any advice is appreciated. 

Thank you in advance,

Kelly