Cannot get Sainsmart 8 Channel SSR board to turn on sprinkler's 24 V solenoid

Question

I purchase a Sainsmart 8 Channel Solid State Relay board to control an 8 zone sprinkler system via an Arduino Duemilanove w/ ATmeg168. The SSR's LED lights up but my solenoids do not activate at all.

I admit I have no idea what I am doing. But here's how I connected everything:

I connected the Arduino digital outputs 2 - 9 to SSR inputs 1-8. Also, I connected a 26.6 VAC 650 mA power supply (from my Rainbird controller) to the SSR's VOC and GND connections. Specifically, I connected the wire with the white strip from the power supply to the VOC on the SSR board. The other wire from the power supply was connected to the GND. Each solenoid (two wires) was connected to the SSR outputs - common solenoid wire to the silver SSR connector and the other solenoid wire to the copper SSR connector.

I wrote a simple program on the Arduino to cycle through each Arduino digital output for one minute with a 10 second pause between each relay/sprinkler valve. The blue LED lights up for one minute goes off for 10 seconds and then cycles to the next relay. However, my solenoids are not activated at all.

What is wrong?

Answer 1

You didn't link to the relay module in question (I see you're new so no worries, please try to do it next time ;-)) but I'm assuming it's this one.

If this is the case, then I think you have mistakenly connected the 26.6 VAC supply to what is meant for a 5 VDC supply. If you have this is not good, hopefully it hasn't blown anything (very possible though)

The marking are actually VCC (not VOC) and GND. TO these you need to connect a 5VDC supply as mentioned.

Here is a schematic of one of the relays on your module:

Notice the 5V on the input side of the relay. The "switch" is from pins 3 and 4 with a fuse in series.

For the relay connections, they act like a single pole single throw switch (SPST) and need to be in series with the power source. To switch the power to the solenoids, you need one lead from the power supply (either one as it's AC) to one of the relay terminals, then one of the solenoid leads to the other terminal. Finally the other lead from the solenoid connects to the other supply lead.
Just try to think of the relay as a simple switch.