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[on:]

Hi,


I'm developing a large Zigbee network with a coordinator, several routers and more end-devices.

I tried to install routers near the coordinator as much as I could,, but not all of them are at this situation. I have some routers connect between themselves, but not with coordinator directly.

As all my routers devices work with liPo or li-Ion batteries, when any of the router, without line-of-sight, exhausts the battery, the network breaks down.

I said that because routers have to detect coordinator in the first time it begin to work, so if battery goes down, when I change it, I have to move my device all along the network and come back.


Is there any option for maintaining the network parameters even if the coordinator isn't near enough??

Could it be as simply as modify 'NW', 'JV', 'NT' or 'NO' parameters??


Thanks in advance!

Regards.

[Reply #1 on:]

I tried to install routers near the coordinator as much as I could,, but not all of them are at this situation. I have some routers connect between themselves, but not with coordinator directly.

This is fine.

As all my routers devices work with liPo or li-Ion batteries, when any of the router, without line-of-sight, exhausts the battery, the network breaks down.

Routers should be mains-powered. Failing that, the network topology and physical layout needs to allow for sufficient redundant routes.

I said that because routers have to detect coordinator in the first time it begin to work, so if battery goes down, when I change it, I have to move my device all along the network and come back.

This is not my understanding. The router should retain ID, OP, OI, CH, etc., and even if the coordinator is not present when the router is powered back on, it should work. Communication with the coordinator is only required when first joining the network, and powering a router down does not break the network association. I've done this and verified that it works this way.

Is there any option for maintaining the network parameters even if the coordinator isn't near enough??

Could it be as simply as modify 'NW', 'JV', 'NT' or 'NO' parameters??

In general, I wouldn't go twiddling with too many parameters, stick with the defaults as much as possible. NW forces a router to leave the network if it loses contact with the coordinator, I'd leave it at its default value, which is disabled. NT and NO are options for network discovery (ND command), which is really just reports network information.

If the coordinator is replaced, the new one may choose a different values for OP, OI, CH, and this can cause other devices on the network to not be able to communicate with it (although they will continue to communicate with each other as noted above). See "Replacing a Coordinator" in the product manual. JV=1 may help this, but I've not tried it myself, and I'm not sure if this is the problem you're seeing.

[Reply #2 on:]

Thanks Jack!

I'm going to configure my devices, and I'll try this!

I never remove coordinator but when I switch off the router for a long time (simulating battery breaks down), it needs some time to add again to the network. So, I'm going to check the default params for any change.

[Reply #3 on:]

when I switch off the router for a long time (simulating battery breaks down), it needs some time to add again to the network.

Hmmm, how much time does it need, and how are you judging when it is added again to the network?

Just to make sure I was remembering correctly, I did the following experiment. This is a network with six routers and no end devices (and one coordinator of course). Router1 sends data to Router2 and also to Coord. Router2 sends data to Coord only.

1. Powered down Coord and Router2.
2. After a few minutes, powered up Router2, leaving Coord off.
3. Router2 continues to receive data from Router1, without long delay.

[Reply #4 on:]

Hi,

thanks Jack!

I have repeated your test and it worked (with default parameters).

Now, I'm going to try a nonsense. I change the 'sleep mode' to 'pin hibernate' in one router (I know it must be always awake), and let it falls asleep for an hour, then I wake it up, and try again the communication.

I think this last test will be worst case, and the router has to join the network again, so if it doesn't find coordinator first, it won't work.

Regards!

[Reply #5 on:]

Now, I'm going to try a nonsense. I change the 'sleep mode' to 'pin hibernate' in one router (I know it must be always awake), and let it falls asleep for an hour, then I wake it up, and try again the communication.

I would have to agree that is nonsense, as the product manual (p34) says:

A router has the following characteristics: it
•Must join a ZigBee PAN before it can transmit, receive, or route data
•After joining, can allow routers and end devices to join the network
•After joining, can assist in routing data
•Cannot sleep--should be mains powered.
•Can buffer RF data packets for sleeping end device children.

[Reply #6 on:]

Thanks again Jack!

It was only a test.

If the router fall asleep by pin hibernate or other configuration, it loose the network configuration.

Regards!