Transducers (PLC savvy help please)
 

Does anybody know a place where you can get Teansducers for the following;

Ca
Mg
KH
PH
Temp

I am looking to get a PLC going and i know the aquarium specific monitors are quite expensive as are the field type for manufacturing plants as they are Class 1 Div 2 rated and i do not need explosion proof (well I hope I dont have an explosion lol) Any other help on cheaper monitors would be greatly appreciated.

Also does anybody know what the monitors (pinpoint or Milwaukee) transmit at? ie. 1-10 volts etc

Thanks

Hi,

Try http://www.vernier.com/probes/ for all the probes you could ever wish for!

Not a bad price either. You will need some sort of gain circuit or a/d conversion to make them work on PLC's. Also you will need to poll some of those probes one at a time and take a reading as some of the probes conduct a small current through the water and if 2 are operating at the same time, you will get erroneous readings.

Polling should be a sinch with a PLC though.

Hope this helps!

VR

Ya i figured that, my thoughts were some sort of power conditioner or some sort of a/d conversion. Thanks for the help and the link they are a good price!! Hard to find good spec sheet though.

Heres a few links to get you going. Ive not got round to testing them yet but im sure they would work great:

Ph:
http://www.csaba.ch/index.php?option...d=28&Itemid=30

Salinity:
http://www.octiva.net/projects/ppm/

i would check with fish farm suppliers they might have something for comercial hatcheries

I am interested too. Lookin at all the links. I'm using a RTD for temp, with a RTD/4-20MA converter for 4-20ma PLC analog input.

Where did you find you RTD? I was looking at these guys ok price (like $75), custom built and they are in town

http://www.wika.ca/

Personally, I get alot of stuff from work. I'm an industrial Electrician. But check out http://www.omega.com/ They canadian and really great prices. They have HUGE catalog's that they will send ya free..

A good source for all the other parts you may need is www.digikey.ca