Expert on solid state relay needed.....

[planekrazie]

Hello guys,
I have a hobbycnc pro board that is used to run my cnc router. I bought a Kyoto KD20C40AX SSR which is 3-32v dc input and 24-240v ac output.
My problem is I can not get it to switch the router on from my hobbycnc board. I am using pin 16 for the + input on the board and the - is connected to my ground connector on the board. I have attached a pdf file of the circuit. The SSR circuit is at the bottom of the page. By looking at the diagram, It showes a 2.2k resistor connected across both input pins. Is this correct? If anyone has a clue on how to wire up one of these SSRs, Please go through it step by step with me. I have only a few hairs left on my head and Id like to keep them There is something I am missing but I can not figure out what it is. I also made a crude drawing of the way I have it hooked now. See if I am missing something. If I need to add a externial DC power source please explain how to do this without killing my LPT. I believe I already killed port 1 and 17 because I touched the 24vdc pos side of my cooling power to the + on the SSR.
Oh well. Hope someone can help.
Thanks Steve

[jalessi]

Connecting the SSR+ to pin 16 and - to ground should work.

Have you measured the voltage on pin 16, is there at least 3.3 volts?


Have you configured the SSR for output 1?

See attached image

[LeeWay]

If using Mach 3, you also have to turn the spindle on in the motor tuning screen.
I use only the SSR. No resistors in my circuit. My router runs on a laptop, but I use a C10 BOB which needs an additional 5 VDC input to work right.

If you have something shorted, I would really test everything first. Use a wall wart power supply to test the SSR. I don't know if you will actually hear a click. I doubt it really. This should be tested by appling DC voltage and checking the other two poles for continuity. It is basically just a switch. If it is off with no continuity after you applied the correct range of voltage, then it is a paper weight.

A multimeter is a crucial tool anytime one is working around anything with wire that carries voltage.

[planekrazie]

Yes, I have done everything mentioned above. Pin 16 has 4.10v without the SSR Wired. With it wired I only read 2.78v. There is a small led on the SSR that might be eating some of the volts. If I wanted to add to the voltage with another power source, How would I do this?
Thanks guys
Steve

[LeeWay]

I am not familiar with the Hobby cnc board.
Someone else will have to step up here.

You may actually need a resistor on this one.

[vger]

Steve,
Sounds like the SSR you have draws more current than the hobbypro can deliver. A simple transistor buffer may do the trick for you. Take a 2N3904 (or similar) NPN transistor and connect the base through a 4.7 Kohm resistor to the hobbypro output pin. Connect the emitter of the transistor to gnd. Connect the collector of the transistor to the - (neg) side of the SSR and the + (pos) side of the SSR to either +5 or +12 V.

Steve

[Al_The_Man]

Also you could use a 2n7000 it needs no resistors, it is TTL to up to 60vdc driver.
There are a few previous posts showing this.
Al.

[vtxstar]

Is THIS the driver pcb you are using?

If so, I don't see that pin 16 is called out in their port usage.

As Vger says, it sounds like the port pin is being pulled out of spec due to too much current.
On the other hand, an SSR should just require about the same as an LED. Many are opto-isolated internally.

An SSR should just need the +VDC on the + connection and 0VDC on the - connection to turn on the AC side.
Use a common light bulb in place of the router until you get thing sorted out.

If you are really feeling brave, remove the 2.2k resistor to see if it helps.
It was in the drawing to be used with a +5VDC supply and pin 16 acting as a current sink, not a source as you are attempting.