Node running on supercaps and a solar panel.
-
even if it drains the battery when the GW is dead, it is no big deal as you just have to wait for some sunlight
-
For this type of comparison, I think you're better off charging up the supercap in a standardized way and then running with the solar panel disconnected. Otherwise, how recently and how long the supercap was charged to full capacity can affect the rate of discharge.
-
Maybe it has to do with the harvesting chip. My graph looks like a sawtooth from day to day.
@gohan there is no harversting - this is just 30F cap connected to a node.
I have two setups:- BQ25570 + 2x10F supercaps in series and a small solar panel connected to a node. This is an excellent setup which can last for days without recharging
- 30F cap connected directly (initially I tried it via mcp1640) to a different node. The above graphs are from this setup.
I am re-measuring it them right now as the code was wrong.
-
@gohan Well, the point is that signing does take more tx time. Therefore, voltage does drop upto 0.2-0.3V.
I am not sure about irregularities though
@alexsh1 with signing you also get message bursts. Not only is the max size data transmitted for every signed message, two more messages are exchanged; a nonce request (small) and a nonce (big).
Do you feel secure today? No? Start requiring some signatures and feel better tomorrow ;)
-
@alexsh1 with signing you also get message bursts. Not only is the max size data transmitted for every signed message, two more messages are exchanged; a nonce request (small) and a nonce (big).
@anticimex said in Node running on supercaps and a solar panel.:
@alexsh1 with signing you also get message bursts.
That's clearly visible on the graph.
-
I have got my hands on 30F 2.7V supercapacitor.
With it was charged for the first time, it only lasted sending 2583 times (1 time a minute voltage and an 20ms LED pulse and then sleeping; sleeping consumption is 4-5uA). The number is a bit disappointing. It is however connected via boost MCP1640 to provide the node with a stable 3.3V. I may try to get the supercapacitor connected directly to the node to see if I can extract more packets.
@alexsh1 said in Node running on supercaps and a solar panel.:
I have got my hands on 30F 2.7V supercapacitor.
With it was charged for the first time, it only lasted sending 2583 times (1 time a minute voltage and an 20ms LED pulse and then sleeping; sleeping consumption is 4-5uA). The number is a bit disappointing. It is however connected via boost MCP1640 to provide the node with a stable 3.3V. I may try to get the supercapacitor connected directly to the node to see if I can extract more packets.
Supercap connected directly to the node stopped working at 2V.
I got about 8949 packets (10ms LED and sent voltage every minute. No signing). It has been running about 6 days.
Hello! It looks like you're interested in this conversation, but you don't have an account yet.
Getting fed up of having to scroll through the same posts each visit? When you register for an account, you'll always come back to exactly where you were before, and choose to be notified of new replies (either via email, or push notification). You'll also be able to save bookmarks and upvote posts to show your appreciation to other community members.
With your input, this post could be even better 💗
Register Login