Relay Glitching

So my setup is an Uno, relay and 12v actuator. The Uno and relay are powered separately (15v and 12v respectively).

My goal is to extend and retract the actuator 500 times and then stop.

My problem is that somewhere between 30 and 100 cycles the actuator will not retract. It then continues with the program and extends once more and continues going back and forth. This double extension is very problematic for my setup. I do not believe it is my coding because the Uno still sends a signal to power the relay in the retraction direction because the the LED lights up on the relay in retraction direction. Could there be a problem internally with the relay?

Thanks

Here are some pics and code to help visualize.

Big_Arm_v2.ino (524 Bytes)

rsz_1arduino_2.jpg

rsz_2arduino_3.jpg

One possibility is that the actuator power supply is overheating and not supplying the required current. Post links to the product pages or data sheets for the actuator and the actuator power supply.

http://www.progressiveautomations.com/linear-actuator-with-potentiometer

18 in stroke, 35lbs

http://www.progressiveautomations.com/ac-15

Those will work together.

Another possibility is that the relay contacts are burning. It would be much, much better to use a suitable motor driver, like this one. I use it with a similar actuator and power supply, and the system is perfectly reliable.

Is it possible for the contacts to burn and go back to working?

Is there any way to test to see if this is in fact my problem?

Also does this motor driver just replace my relay?

Is it possible for the contacts to burn and go back to working? Yes, the contacts become intermittent.

Is there any way to test to see if this is in fact my problem? Put a narrow strip of paper between the contacts, press the contacts together, pull the paper out smoothly and take a look at it. That will also clean the contacts, for a while.

Also does this motor driver just replace my relay? No, it also provides speed control and fully reversible motion.

Awesome, Thanks for the help.

I will try your idea and report back if it has helped my situation.