Spike relays not working

[Broncobot_kae22]

Our spike relays are not working. I have an amber light on the relay. When button is pushed nothing happens. It is plugged in with a PWM cable to the relay port on the roboRIO. What can we do to fix this? We had a coder right the correct code for us but still nothing.

[BitTwiddler]

Originally Posted by Broncobot_kae22

Our spike relays are not working. I have an amber light on the relay. When button is pushed nothing happens. It is plugged in with a PWM cable to the relay port on the roboRIO. What can we do to fix this? We had a coder right the correct code for us but still nothing.

Are you absolutely, positively sure that the pwm cable is plugged in with the correct orientation and fully seated within the socket on the Spike? Seems like 90% of our troubles with Spikes can be traced to that cable.

[Peyton Yeung]

We had an issue with a spike relay this year. We couldn't figure out why it wouldn't work since the code seemed right so we swapped it out with another one and the new one worked.

[cbale2000]

Originally Posted by Broncobot_kae22

Our spike relays are not working. I have an amber light on the relay. When button is pushed nothing happens. It is plugged in with a PWM cable to the relay port on the roboRIO. What can we do to fix this? We had a coder right the correct code for us but still nothing.

Check the fuse on the spike? Make sure it isn't bad.

[jwallace15]

Originally Posted by cbale2000

Check the fuse on the spike? Make sure it isn't bad.

If I'm not mistaken, the relay should still follow code if the fuse is bad (I.E. you will hear the relay click, and will see a change in light code). Whatever accessory you are trying to manipulate will not work, however.

I'm going to agree with Mr. Tanguay and Peyton. That sounds like a bad cable or a bad unit. Consider swapping one of them (try one at a time, this can help you isolate which piece of the puzzle was faulty, and can help you identify what to throw away!).

[m1tche11d]

Before you swap out the Spike, if nothing else seems to be working, try rotating the PWM cable so that it is plugged in the wrong way. This has fixed the problem for us before.

I don't think this is a common problem, and there's only one other case that I know of where this has worked, but it's worth a shot.

[SuperBK]

I would not recommend just turning the PWM cable around. Verify that's its correct and leave it, or swap it with another one. Did you try another one?

Here is my recommendation. Measure the voltages on the roboRIO relay port before while actuating whatever buttons are programmed to turn it on. Put the Negative probe on GND. That is the pin closest to the edge of the roboRIO. Measure the voltage on one of the other two pins. The center pin is reverse, and the inside pin is forward. When actuated, it should go to 5V. If you don't see any actuation, then its a code issue, or in a rare case, a bad port on the roboRIO. Be careful not to short the pins together while probing, that wouldn't help things any.

If voltages go high and low (5V and near 0), then plug the cable in and measure it at the other end, or use the continuity function of a meter to test if the pwm cable is good. If the cable is good, then its a bad spike. Double check that its + and - are wired correctly.


For details on the port, see the roboRio manual. http://www.ni.com/pdf/manuals/374474a.pdf

[Broncobot_kae22]

We are almost 100% sure that the pwm cable is plugged in correctly.

[Broncobot_kae22]

We have 3 brand new spikes and still nothing. We are not even getting 5v coming out of the roborio

[Broncobot_kae22]

It's a self setting circuit breaker.

[Broncobot_kae22]

We did try plugging in the pwm backwards and nothing worked.

[Broncobot_kae22]

We Checked The voltage on roborio and still not getting 5v on forward or reverse. I'm not getting a ground on the ground pin.

[Alan Anderson]

Originally Posted by Broncobot_kae22

We have 3 brand new spikes and still nothing. We are not even getting 5v coming out of the roborio

What color is the power LED on the roboRIO? If it's red, you most likely have something shorting the 5 volt power bus. Check for debris around the roboRIO's connectors. Use a very bright light to search for something like a tiny strand of wire, or a layer of aluminum dust, that could be a problem. It would be contacting the center pin on any of the DIO, PWM, or Analog ports. It could be anywhere.

If the power LED is green, focus on the code.

[broncobots5201]

the power light is green
the status light no light
the radio light no light
the comm light is green
the mode light is green
the rsl light is orange

[Alan Anderson]

Thank you for the detailed description. It might have given the explanation.


Power steady green means there's nothing wrong with the power. When you said you're not "getting 5v coming out of the roborio", where were you measuring?

Status off means the roboRIO has completed its selftest without errors.

Radio off means there's no USB radio. That's normal.

Comm steady green means the Driver Station is properly connected.

Mode steady green is the big clue -- it means the robot is enabled in Autonomous mode. Switch it to Teleoperated and see whether things start working as you expect.

RSL steady orange means the robot is disabled. That's not compatible with mode being green. Are you sure it's not blinking?