Power to Temp sensors and WC

[rfeyer]

I am trying to use WC with 3 DS20b18's attached to them as well as one Humidity sensor.
Since it seems more logical to have separate power supply to the sensors, is it possible to split the power BEFORE to enters the WC?
The current power supply I use is 9V, 1.11A.
If I split the power before it get's into the WC and divert it to WC and Temp sensors, will that solve the problem?
 
Rainer

 

[LarrylLix]

What problem are you trying to solve? You didn't state what the problem is.
 
The WC8 board has it's own splitter for the power supply. I don't see how splitting it outside the WC8 board would make any difference for 3 sensors taking micro-power each.

 

[rfeyer]

I don't really have a problem yet - only have one sensor attached and it works fine. But plans are to add 4 more at some point, and I am reading on this forum that the power of the temp output would be too taxed.
So, I am trying to learn ahead of time if a separate power source for the temp sensors is needed, which some already mentioned on this forum.
What I do not know is: when the 9v 1.11 amp enter the WC - is that reduced when it exits the Temp outlet, and which case splitting the original power would make sense, or, is WC utilizing the whole 9v 1.11A and therefore splitting outside would not solve anything.

Rainer

 

[LarrylLix]

The WC8 board only uses less than 20% of that power. CAI can provide a more accurate figure.
 
The sensor spec sheets show them taking micro-power so they could be operated in parasitic mode off the data line. You could probably run 100 of them from the WC8 board 1Wire terminal but the WC8 only has firmware provisions for 8 units.
 
If you split the crude power supply you would need a voltage regulator to bring the voltage down to 3-5v the same as the WC8 board has.

 

[rfeyer]

Thank you - that helps!
I will wait until the next batch of Temp sensors arrive and see if all of them together are accurate.
Again, TY for helping!
 
Rainer

 

[LarrylLix]

Not a problem. Nice to see somebody else on their way.

 

[Efried]

The WC8 board only uses less than 20% of that power. CAI can provide a more accurate figure.
 
The sensor spec sheets show them taking micro-power so they could be operated in parasitic mode off the data line. You could probably run 100 of them from the WC8 board 1Wire terminal but the WC8 only has firmware provisions for 8 units.
 
If you split the crude power supply you would need a voltage regulator to bring the voltage down to 3-5v the same as the WC8 board has.

 

Thank you - that helps!
I will wait until the next batch of Temp sensors arrive and see if all of them together are accurate.
Again, TY for helping!
 
Rainer

If you have power supply having floating ground, you would introduce more problems by adding a separate power supply rather than solving problems. In my scenario I'm blending PC-supply for fans with grid supply for the rest, using power MOS SSR. The PV-side is not earthed ;-) The board does have some issues with sensors lost, nor recognizing some on start-up, but I would not relate that to my power supply.

 

[rfeyer]

Great to know - TY - will do some reading on Floating ground.
By Grid supply, you mean actual AC?