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Battery value's rfxsensor
Posted: Sun Jul 08, 2007 11:55 am
by Snelvuur
Hi,
What would be considered "bad" "weak" and "good" for the battery sensor?
i know between 4.5 and 5 volt is ok right?
And between 4.0 and 4.5 i would asume "weak" and below that is bad? Is something like that ok? since i dont have these value's yet

Battery value's rfxsensor
Posted: Sun Jul 08, 2007 12:54 pm
by b_weijenberg
The supply voltage transmitted by the RFXSensor is the voltage behind the 5volt regulator. Due to additional loss in the power switching circuit that feeds the1-Wire a voltage of 4.7 is normal. If the battery voltage drops below 5.3volt then you have to replace the empty battery.
Battery value's rfxsensor
Posted: Sun Jul 08, 2007 1:16 pm
by Snelvuur
well i receive 5.01 voltage, i know the 2.xx voltage is for my humdity readings.
rfxsensor02f2[voltage]=5.01] <- battery?
rfxsensor01f1[voltage]=2.35] <- humidity
So because i only receive this value, which value's should i take for the bad/weak/good idea?
Battery value's rfxsensor
Posted: Sun Jul 08, 2007 1:38 pm
by b_weijenberg
the 5.01V is not the battery voltage but the 1-wire supply voltage!
So if this voltage becomes below 5.01v then it is expected that the 9V battery is empty.
Battery value's rfxsensor
Posted: Sun Jul 08, 2007 6:17 pm
by Snelvuur
but there is no in between? I thought it was sending out the battery status too

so i could have a little indicator page which shows the devices that might need replacement.
Battery value's rfxsensor
Posted: Sun Jul 08, 2007 6:53 pm
by b_weijenberg
RFM
http://www.rfxcom.com/documents/RFXSensor.pdf page 6 & page 8 where the packet format is described including the battery empty indicator.
Battery value's rfxsensor
Posted: Mon Jul 09, 2007 11:42 am
by John Downe
Snelvuur, with Bert's advise some time ago I connected the RFXSensor battery to the A/D input in the RFXSensor (Mine is Type 3) and I now get the battery actual voltage to 2 decimal places into HomeSeer - so I can manually or automatically identify a dying battery. Not sure with your humidity sensor whether you can also do this though
JWD
Battery value's rfxsensor
Posted: Mon Jul 09, 2007 11:44 am
by b_weijenberg
John/snelvuur,
The humidity sensor is using the A/D input already and it is therefore not possible to connect the battery to this input.
Bert