Node freezing up

[ferpando]

Hello,

I have a node that every once in a while just stops responding.
I have to unplug it to get it back working.
It is strange because it doesn't appear to be a reason.
Anyone had issues like this before?

[korttoma]

I had similar behavior when I accidentally feed 5V to the NRF24L01+ so my guess is a power issue like in most cases. Check the voltage on the NRF24L01+.

[ferpando]

@korttoma
Yes I did check the power but maybe is a defective module?
It only happens when not connected to the console, so it's hard to track down

[Magiske]

What are you powering it with ?? 5v usb or battery ??

[AWI]

It happened frequently to me when using relays (inductive load). Spikes on the powerline can easily freeze the radio.

[GuyP]

Can you give more details of what your node is? what hardware have you used? do you have a circuit diagram?

[ferpando]

@Magiske
12V power supply

[ferpando]

@AWI
Relays are isolated using opto-couplers so it should`t be a problem.
The relay board is this or very similar:

http://www.ebay.com/itm/Durable-New-16-Channel-12V-Relay-Module-Interface-Board-For-Arduino-PIC-ARM-DSP-/331477749403

Power goes to the relay board and then it powers the arduino

[Magiske]

And you have added a cap for the radio ?
Try to add a blink, just to see if the board crashed/freezes. If not it's properly the radio.

[ferpando]

@GuyP
sorry no diagram, but the node is basically an arduino with radio connected to this relay board

[ferpando]

@Magiske
Yes it has a cap on the radio.
What do you mean by add a blink?

[Magiske]

Just add blink code or add an ekstra led to see if the code is running..

[ferpando]

@Magiske
Ok got it.
I have a led on board, so I'll make it blink to see if it is still alive

[AWI]

@ferpando The optocoupler takes care of the load on the Arduino outputs. What I tried to say is that the inductive load of the relays on the power lines can be substantiall. I there is any sharing of power (same supply) of the relay and the radio it is very hard to avoid lock-ups.

below an excerpt from Jeelabs

[ferpando]

@AWI
I don't have an oscilloscope to test this.
I'll try to power both devices separately, but at least they always have a common ground. Could this also affect the radio?
Adding some capacitors could improve things?

[AWI]

@ferpando A common ground is ok (and necessary).. A capacitor can improve things. Many times it is trial & error. What worked for me is having a seperate regulator and decoupling capacitor of 470uF for the feed to the relay. It is hard to read the schematic of the relay board on e-bay but measures like a diode over the relay-coil need to be in (and probably are). Switching inductive loads with the relay can also introduce EM problems.

It's science... using Solid State relays is a long term reliable (short term expensive) alternative. ... good luck, there may be experts around on the forum.

[ferpando]

@AWI
Looks like it has a regulator and a 1000uF capacitor plus a smaller one.
I'll try to add a second regulator with capacitor just for the arduino and see what happens

[AWI]

@ferpando That certainly looks like a power supply. Please keep me informed.

[TimO]

I have exactly the same Problem. But I'm not sure the relays are the problem.
I've added a keep alive message to know when it stops working and implemented a watchdog.

[ferpando]

@TimO
Could you elaborate a bit more about the watchdog?

[Magiske]

@ferpando You can enable a watchdog timer on your Arduino. If your code hangs your Arduino, it should reset/reboot it. But not sure that would reset the radio.

Found good description -> http://www.megunolink.com/how-to-detect-lockups-using-the-arduino-watchdog/

[vladimir]

@ferpando, @Magiske, You solved this problem? I realized what the problem, but unfortunately, I do not understand how to solve it. Can you explain exactly how to change node?

[AWI]

@TimO said:

I have exactly the same Problem. But I'm not sure the relays are the problem.
I've added a keep alive message to know when it stops working and implemented a watchdog.

That sounds like you keep the motor running and accept that the car crashes every once in a while Better to find the root cause of the "freeze" and eliminate it.

[TimO]

@AWI You're right of course! But ... if the Arduino is the root of all evil in this case, it will reset once in a while but still work. If it still freezes it could be the radio that crashes. So I'm still trying to solve the problem.

All parts use the same 5V source (which I already switched) but the radio of course is connected through a regulator. If the watchdog solves the problem (so the radio is not the problem) I will add a bigger capacitor which I already ordered.

[ferpando]

I made this regulator based on this schematic to power the node independently, to see if it solves the problem.

[RJ_Make]

Does this node by any chance have a temp. sensor also?

My nightmare.. http://forum.mysensors.org/topic/338/reliability/3

[ferpando]

@ServiceXp said:

http://forum.mysensors.org/topic/338/reliability/3

Mine doesn`t at the moment, but should be easy to add.

[Nuubi]

Any update on this?
Asking since I also have a multisensor that locks up every now and then. Thinking of some way to reset the radio a couple of times per day.
Any suggestions how to implement this?

[ferpando]

@Nuubi
No more node lock-ups since I installed that power supply, so it works as expected.