Discuss this pageDisclaimer: I am not responsible for what people (other than myself) write in the forums. Please report any abuse, such as insults, slander, spam and illegal material, and I will take appropriate actions. Don't feed the trolls. Jag tar inget ansvar för det som skrivs i forumet, förutom mina egna inlägg. Vänligen rapportera alla inlägg som bryter mot reglerna, så ska jag se vad jag kan göra. Som regelbrott räknas till exempel förolämpningar, förtal, spam och olagligt material. Mata inte trålarna. Anonymous
Mon 31-Mar-2008 14:43 | While I quite like the idea of the plant monitor, I wonder what the effects of the sensor will be on the system.
Current flows. Electrolysis will happen. The electrodes will dissolve over time. There's a magnetic field, etc. | Anonymous
Thu 3-Apr-2008 09:40 | At University of Gent (molecular genetics department), we weigh the plants to determine if they need water. This way we can water them very precisely and there's no milliliter of water given to much or to little.
-femeref | Anonymous
Wed 9-Apr-2008 15:47 | One interesting thing missing in the schematics is a suitable value for the capacitor. | Anonymous
Wed 9-Apr-2008 15:56 | The amount of current would be very small. And the time it flows can be minimized by providing 5V on the sensing side when not measuring resistance, in effect giving very ner zero volts of difference between the electrodes.
Electrolysis would happen to a very small extent, but it can be minimized in the same way as the current.
Time to put that gold jewelry to use! It won't dissolve if used as electrodes.
The magnetic field would probably not be strong enough to be measurable with affordable instruments, given the small current. | Anonymous
Thu 10-Apr-2008 11:42 | Plants tend to grow, thus gain weight. How do you calculate the amount of plant growth?
-webpresence04 at soulsurf se
At University of Gent (molecular genetics department), we weigh the plants to determine if they need water. This way we can water them very precisely and there's no milliliter of water given to much or to little.
-femeref | lft
Linus Åkesson
Thu 10-Apr-2008 20:25 | One interesting thing missing in the schematics is a suitable value for the capacitor.
Good point. I'm using a 10 uF electrolytic capacitor. | Anonymous
Mon 14-Apr-2008 21:35 | lft wrote: 10 uF electrolytic capacitor Thanks! | Anonymous
Tue 22-Jul-2008 11:51 | The amount of current would be very small. And the time it flows can be minimized by providing 5V on the sensing side when not measuring resistance, in effect giving very ner zero volts of difference between the electrodes.
Don't even need to do that, as the capacitor will charge up until there is close to zero volts across the resistor (in this case, the soil). |
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