Engineer/Programmer for Prototype temp/RH logging

Forum 2005-2010 (read only) Hardware Development
9

o... one Arduino UNO can monitor 4 of the SHT15's

Yes, but if you don't mind plenty of cables, one MEGA - http://arduino.cc/en/Main/ArduinoBoardMega2560 - has 70 I/O lines so it can handle approx 20 temphumid sensors and fans. It sells for ~$65 ...

I like the XBEE architecture proposal as it keeps the room clean of cables. But is it part of the requirements?

If you do XBEE I think you want one XBEE per tank, that has one sensor + one fan.

XBEE - $30 (including some board thingie)
SHT - $38
FAN - $6
Power supply - $10

$85 - so almost equal in price but no wires and maximal modular. So the price we can say the price will be approx $100 per tank no matter what architecture. So which architecture to choose depends on the other requirements of the system than price

So Steven, can you sum up the requirements for us (single sentence per requirement please)

Here are some as a starter, some may apply some not up to you Steven.

  • the system must monitor temperature per tank

  • the system must monitor humidity per tank

  • the system must activate a fan at XX degrees F/C per tank

  • the system must deactivate a fan at XX degrees F/C per tank

  • the system must have settings per tank

  • the system must have a manual override for all fans [ON/OFF]

  • the system must sample temperature every 10 seconds

  • the system must sample humidity every 60 seconds

  • the system must apply a warning when temperature is outside the range [XX..YY]

  • the system must apply a warning when humidity is outside the range [XX..YY]

  • the system must have a local feedback about its working condition (might be a blinking LED (without delay :slight_smile: )

  • the system may not be noisy at night (not explicit enough)

  • the system must be save for the frogs (not explicit enough)
    ==> - the system must work on 5Volts

  • etc ...