Node freezing up

[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.