Humidity Logger
Moderators: adafruit_support_bill, adafruit

Humidity Logger

by exp0sure on Wed Nov 14, 2012 7:20 am

I want too hook up 2x humidity sensors to an Arduino and log the data to an SD card. 1 sensor should be in the attic so I would want a wireless connection here. Would it work with the following components?

2x Sensiron Temperature/Humidity Sensor - SHT11 (ID: 246)
2x XBee Module - Series 1 (ID: 128)
1x Adafruit Data logging shield (ID: 243)

I haven't used an XBEE yet but do I understand it correctly that I can just hook up a XBEE to the Arduino and one to the Humidity sensor and then simply read/send values to the humidity sensor (those 2 XBEEs create a wireless serial connection)?

To hook up the second serial humidity sensor I'd probably need a second serial port? (either soft port via library or multiplexer to switch between sensors?)

Also can I assume that I can access the RTC in the logging shield to use it as a timer?

Posts: 2
Joined: Wed Nov 14, 2012 7:16 am

Re: Humidity Logger

by adafruit_support_bill on Wed Nov 14, 2012 7:39 am

Yes, this can be done, but I think you need the Series 2 XBee. Here is a nice writeup on how to interface the sensor to the XBee: ... ature.html

Since Arduinos are 5v devices and the XBees are 3.3v devices you need something like the XBee adapter to shift the logic levels.
You can interface more other remote sensors via the same XBee. A local sensor would require just 2 pins. You can use the RTC on the logger shield for timing.

For a great reference on remote sensing with XBees, I highly recommend Rob Faludi's book:
User avatar
Posts: 36490
Joined: Sat Feb 07, 2009 10:11 am

Re: Humidity Logger

by exp0sure on Wed Nov 14, 2012 4:39 pm

Thanks! I'll have a read...
Posts: 2
Joined: Wed Nov 14, 2012 7:16 am