Power consumption TTN Gateway


#1

I want to know the (average) power consumption of the TTN Gateway, because I want to have it powered from a battery for a while. Can anybody tell me a spec or an estimation? Thank you.


(Matthijs Kooijman) #2

This is not an answer to your question, but it's related, so I'm posting it here anyway. I just measured the power usage of a Lorank8 gateway on its USB 5V input:
- Board startup 400-500mA
- Radio startup up to 900mA
- Idle: 650mA
- Transmit: around 750mA

I rounded things a bit and especially the TX power usage is a bit rough, since I used a multimeter, not a scope, so the real peak might have been higher.

The idle power usage on the 230V side, using the supplied 2A USB adapter is about 4W.


#3

Matthijs, Thanks for replying!
So, an average of 5W would be a good guess.


(Matthijs Kooijman) #4

Note that AFAIU the TTN gateway does not run a full linux stack but has a smaller control chip, so I would think its power usage could be significantly less than this, but someone will just have to measure that :slight_smile:


#5

Many thanks to Matthijs for his valuable help. In fact, it would be really useful to have detailed specs of the TTN Gateway. Does anyone know if there is any place where some of its basic HW info can be accessed in order to make an estimate as realistic as possible? Peterq question may be of interest for many people. I would also need to check power consumption before placing an order, and available info at the shopping page seems a little scarce in this aspect.


#6

I think it will become clear after the Kickstarter rewards arrive with the backers. It's supposed to be only a matter of weeks now (fingers crossed, as I'm a gateway backer myself)


(Sven) #7

The board runs on 3.3V, the rough current consumption figures are

Board on, processor in reset mode, all peripherals off: 50mA
Board on, processor active, all peripherals off: 200 mA
Board on, processor active, lora listening: 500mA
Board on, processor active, lora transmitting+(wifi/ethernet): 1 A

There will be conversion losses at the onboard dc/dc converter, so a 12V power supply will need to supply at least ~333mA for the gateway to work properly.

These figures are rough integrated averages. This means that the peak currents of all peripherals on board, and thus the total power consumption can differ heavily.


(Sven) #8

Peter, since the subsystems of the gateway are individually controllable, you can reduce as much power as you would like. The bottom line for lora is 500mA as this is the idle current for the semtech 'gateway' ic + processor current to catch events from the modem.


(Jose Marcelino) #9

Thank you that's interesting information. So a 12V car battery could theoretically power the gateway for about 5 days and maybe with a 20W solar panel (and actually having sun!) it could keep on running.

When you say the subsystems are individually controllable how would you go about disabling things? Will I need to recompile a firmware or can it be done "on-the-fly".

Could be interesting if you could have WiFi/Ethernet off until there was LoRa traffic.


(Sven) #10

At the moment it would require a firmware change/custom firmware.


#11

Thank you very much for the information you provided!
(I didn't respond for a while because of an accident and illness, but recovery has started.)