Battery Sensor with stepup and on/off transistor
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@ht81 Hey, the NRF is directly connected to the battery. only the DHT use the stepup.
i use this stepup: http://www.banggood.com/2Pcs-500mA-DC-DC-1V-5V-Converter-Step-Up-Module-Power-Module-p-945167.html
Just put a transistor in front of the stepup. this is all :)
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@n3ro Why would you need a step up for DHT, I am running DHT11 on 3.3v and it work fine.
@Suresh-Mali My sensor node is powered with two AAA Batts. Over the time the voltage drops down to 1,9v.
The DHT only works with ~3v. so i need the stepup only to power the dht
i use this setup with my multisensor nodes.
http://forum.mysensors.org/topic/1514/multisensor_pir_dht_ldr_battery/3Without transistor the battery is drained in ~2 month (black line)
with transistors in ~10 month
pimatic + MySensors + Homeduino + z-way
https://github.com/n3roGit/MySensors_n3ro -
@Suresh-Mali My sensor node is powered with two AAA Batts. Over the time the voltage drops down to 1,9v.
The DHT only works with ~3v. so i need the stepup only to power the dht
i use this setup with my multisensor nodes.
http://forum.mysensors.org/topic/1514/multisensor_pir_dht_ldr_battery/3Without transistor the battery is drained in ~2 month (black line)
with transistors in ~10 month@n3ro Gr8, makes sense.:+1:
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Hey togehter,
is a battery drain graph like this normal with alkaline batteries?
regards,
n3ro@n3ro said:
is a battery drain graph like this normal with alkaline batteries?
If you mean the sudden drop at the end, the answer is yes. This is called a S curve because it looks like a (very stretched) S. That's the typical behavior of most batteries.
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The fact that you drain the battery in less then 2 months is probably due to the presence detection. I'm assumung this is using passive IR and is always on ? As mentioned by @mfalkvidd the shape is normal.
I use the breakout for SI7021 from Aliexpress and these use very little current. Also, there is no need for a step up, as this sensor works down to 1.8V. For light detection I use a LDR and 1MOhm resistor combination connected to a digital pin for power and analog pin for measuring. Works nicely because I let it settle (I first call the SI7021 to get the temperature and check the battery voltage, then I measure the analog value of the LDR. I only need relative values for light, so LDR is more then accurate enough for me. -
The fact that you drain the battery in less then 2 months is probably due to the presence detection. I'm assumung this is using passive IR and is always on ? As mentioned by @mfalkvidd the shape is normal.
I use the breakout for SI7021 from Aliexpress and these use very little current. Also, there is no need for a step up, as this sensor works down to 1.8V. For light detection I use a LDR and 1MOhm resistor combination connected to a digital pin for power and analog pin for measuring. Works nicely because I let it settle (I first call the SI7021 to get the temperature and check the battery voltage, then I measure the analog value of the LDR. I only need relative values for light, so LDR is more then accurate enough for me.@GertSanders
thx :)I have just ordered some SI7021 for testing.
My Pir sensors are these ones:
http://www.amazon.de/gp/product/B008EGH3FM50 Mikroampere
i dont know if this is aktive or passiv :-/
regards,
n3ro -
It's a passive IR module, and using 50uA, which is about 5 times the average consumption of my temperature/humidity sensors (between 8 and 11 uA depending on the amount of message resends needed).
The nice thing about the module you use is the low voltage it needs to work (0.8V <-> 9V).
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It's a passive IR module, and using 50uA, which is about 5 times the average consumption of my temperature/humidity sensors (between 8 and 11 uA depending on the amount of message resends needed).
The nice thing about the module you use is the low voltage it needs to work (0.8V <-> 9V).
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@GertSanders said:
(0.8V <-> 9V)
Yes. I had a few problems with the 5v PIRs. That's why I ordered this.
