Temperature Monitoring System

[Qmavam]

Hi
I'm starting to put together a system to monitor 20 different temperature locations.
Haven't bought any parts yet, I want to get some input first.
I'm thinking about using a DS9097U.
Two questions:
1) What is the maximum number of sensors that the DS9097U can drive?

2) DS9097U with suffix 009 or the S09 with the addition of a 64-bit address.
What is the advantage/disadvantage of a 64-bit address?

I've looked at this software
http://www.elektroniikka.org/thermometer/?page=screenshots
But don't find a help file and I need help
I do like what I see in the screenshots.

Why would I want a six channel hub board if I can run 20 sensors from
the DS9097U?
Note; I will have three separate areas to monitor, freezers, greenhouse and solar collector,
in case that has something to do with the six channel hub board.

This will be my first digital/software project although I've built many electronic projects,
so please guide me through this.
Thanks, Mike

 

[jaysonc]

Mike,

I use several of these: http://embeddeddatasystems.com/page/EDS/PROD/HA/HA7Net
They are very nice.

Effectively it is an ethernet to 1-wire bridge with 3 1-wire ports. Each port can support 100 devices.

I do not believe there is any technical limit on the number of devices you can put a 1-wire cable, but there are logistical limits based on the interface and the cumulative effect of power drain from the devices.

--
Jayson

Hi
I'm starting to put together a system to monitor 20 different temperature locations.
Haven't bought any parts yet, I want to get some input first.
I'm thinking about using a DS9097U.
Two questions:
1) What is the maximum number of sensors that the DS9097U can drive?

2) DS9097U with suffix 009 or the S09 with the addition of a 64-bit address.
What is the advantage/disadvantage of a 64-bit address?

I've looked at this software
http://www.elektroniikka.org/thermometer/?page=screenshots
But don't find a help file and I need help
I do like what I see in the screenshots.

Why would I want a six channel hub board if I can run 20 sensors from
the DS9097U?
Note; I will have three separate areas to monitor, freezers, greenhouse and solar collector,
in case that has something to do with the six channel hub board.

This will be my first digital/software project although I've built many electronic projects,
so please guide me through this.
Thanks, Mike

 

[Qmavam]

Mike,

I use several of these: http://embeddeddatasystems.com/page/EDS/PROD/HA/HA7Net
They are very nice.

Effectively it is an ethernet to 1-wire bridge with 3 1-wire ports. Each port can support 100 devices.

I do not believe there is any technical limit on the number of devices you can put a 1-wire cable, but there are logistical limits based on the interface and the cumulative effect of power drain from the devices.

--
Jayson

Thanks Jayson,
I see the cost is $155, I'd like to do it cheaper.
Mike

 

[jwilson56]

Check out Hobby-boards.com

I use their master hub

 

[Qmavam]

Check out Hobby-boards.com

I use their master hub

I'm in learning mode.
Why would I want the Master hub and not just a DS9097U?
Thanks, Mike

 

[ericvic]

Check out Hobby-boards.com

I use their master hub

I'm in learning mode.
Why would I want the Master hub and not just a DS9097U?
Thanks, Mike

The DS9097U will work just fine if you have all your sensors hooked up on one cable (daisy chain). If you need to use more of a star topology that is when you would need a Hub.

As for the number of sensors you can easily add 100 temperature sensors to a DS9097U ass long as the cable run is not too long.

I have found no real reason to have the ID chip in the DS9097U. We sometimes have the -009 version and sometimes the -S09 version in stock. It mainly depends on which one has the shortest backorder time when we need to place another order.

Eric

 

[Qmavam]

Check out Hobby-boards.com

I use their master hub

I'm in learning mode.
Why would I want the Master hub and not just a DS9097U?
Thanks, Mike

The DS9097U will work just fine if you have all your sensors hooked up on one cable (daisy chain). If you need to use more of a star topology that is when you would need a Hub.

As for the number of sensors you can easily add 100 temperature sensors to a DS9097U ass long as the cable run is not too long.

I have found no real reason to have the ID chip in the DS9097U. We sometimes have the -009 version and sometimes the -S09 version in stock. It mainly depends on which one has the shortest backorder time when we need to place another order.

Eric

Thanks for the info Eric,
I will stick with the -009, one less thing on the learning curve.
Regarding the cable run, Electrically I don't see much difference between one long run and three
shorter runs connected in parallel.

Is it proper to run parallel wires?

If you do run a Hub, can you use the software to just display one run?
Example; three runs, Freezer, greenhouse and solar collector.

Can I display just the freezers, then pull up the greenhouse screen then solar screen?

Ok, Can I do the same with just the DS9097U?

Thanks, Mike

 

[ericvic]

Thanks for the info Eric,
I will stick with the -009, one less thing on the learning curve.
Regarding the cable run, Electrically I don't see much difference between one long run and three
shorter runs connected in parallel.

Is it proper to run parallel wires?

If you do run a Hub, can you use the software to just display one run?
Example; three runs, Freezer, greenhouse and solar collector.

Can I display just the freezers, then pull up the greenhouse screen then solar screen?

Ok, Can I do the same with just the DS9097U?

Thanks, Mike

Parallel runs are not the same electrically to 1-Wire signals. Some people have setup their 1-Wire networks like and they have run fine and others have had nothing but problems.

The Hub just basically gives you up to 6 branches to make a star network work better. As long as the software you use knows about hubs then the user shouldn't see a difference once everything is setup. Not sure if I explained that very well.

Eric

 

[Qmavam]

Is it proper to run parallel wires?

Parallel runs are not the same electrically to 1-Wire signals. Some people have setup their 1-Wire networks like and they have run fine and others have had nothing but problems.

The Hub just basically gives you up to 6 branches to make a star network work better. As long as the software you use knows about hubs then the user shouldn't see a difference once everything is setup. Not sure if I explained that very well.

Eric

Sorry if this is a repeat, I typed it once and it disappeared.
Ok, the only electrical difference I can see is the terminating resistance would be different with three short cables vs. 1 long cable.
Thanks, Mike

 

[ericvic]

Is it proper to run parallel wires?

Parallel runs are not the same electrically to 1-Wire signals. Some people have setup their 1-Wire networks like and they have run fine and others have had nothing but problems.

The Hub just basically gives you up to 6 branches to make a star network work better. As long as the software you use knows about hubs then the user shouldn't see a difference once everything is setup. Not sure if I explained that very well.

Eric

Sorry if this is a repeat, I typed it once and it disappeared.
Ok, the only electrical difference I can see is the terminating resistance would be different with three short cables vs. 1 long cable.
Thanks, Mike

Mike,

It has to do with signal reflections. You can find more detailed information here.

Eric

 

[EL34]

Eric's hubs are nice because they provide a solid level of power to all the 1 one devices.

Not sure how well that serial adapter does in that regard.
I have used the usb adapter also, but it has a very limited amount of power it can supply.

I don't like to run 1 wire sensors parasitically, I prefer to send power down the one wire cable and power the devices from a solid power supply.
That's just me, I am sure not powered operation works just fine for many.

I have one of the HB 6 channel master hubs.
The nice thing about hubs, besides the power supply, is that there are 3x 2409 switches in the hub.
To be able to read any of the 6 branches, the software has to go to the proper switch and then switch that switch to main or aux to be able to read the sensors hooked to that branch.

I think this makes for a more solid network as opposed to having a bunch of sensors all in a line.
Of course, if you cannot do a star type wire layout and you must have a series arrangement, then the matser hub may not be what you need.

Eric also sells an adapter that can inject power into the one wire cable, so that may be an option also.