Temperature & Humidity sensor for indoor use.

[ckchew666]

Hi,

I've a project require 12 humidity sensor located in indoor. Anyone can recommend?

Can this humidity sensor direct wired to PLC Input (mA or V module) or need a special controller?

While for the indoor temperature sensor, customer is looking for a temperature controller that has 3 high alarm (high, high-high & high-high-high).

I'm using Yokogawa PLC (FAM3).

Thanks.

 

[Pierre]

There are thousand of these devices. You need to provide more specs on what you need.

Range, precision, repeatability, mechanical format desired, physical location, ambiant, local/remote display, price range, supply, signal,...etc

What do you want.

It like saying I need door knobs to go indoor. You will have to many options if you don't narrow your choices/needs.

 

[ckchew666]

There are thousand of these devices. You need to provide more specs on what you need.

Range, precision, repeatability, mechanical format desired, physical location, ambiant, local/remote display, price range, supply, signal,...etc

What do you want.

It like saying I need door knobs to go indoor. You will have to many options if you don't narrow your choices/needs.

Sorry, newbies here.

Range = 0 to 100%rh
Accuracy = +/- 1.5%rh
Stability = less than 1%rh/year
Signal = 4-20mA or 0 - 10V (to PLC analog module)
Price = not sure what's the price range
Location = Indoor (20 - 50 degree Celcius)

Based on these info, is that enough?

Thanks.

 

[Tom Jenkins]

We've had good success with RH transmitters from Omega Engineering.

http://www.omega.com/

 

[Andybr]

The best I have found are manufactured by Rotronic. RH transmitters often have an putput for temperature as well so you may be able to get both variables from a single device.

 

[MarkTTU]

I'll second Tom's advice. I've been very happy with the RH/temp sensors from Omega.

To calculate RH you have to know temp so most (not all) RH sensors also have an output for temp; the ones that don't have this output are usually just missing the connection header for the temp output (ie its there, but no way to wire it up).

 

[dash]

Sorry, newbies here.

Range = 0 to 100%rh
Accuracy = +/- 1.5%rh
Stability = less than 1%rh/year
Signal = 4-20mA or 0 - 10V (to PLC analog module)
Price = not sure what's the price range
Location = Indoor (20 - 50 degree Celcius)

Based on these info, is that enough?

Thanks.

All is fine except for the +/- 1.5% accuracy. That will cost you quite a bit. More typical is +/-2% to +/-3%. Especially when you thow in a range of 0-100%. That may be available if the range is limited to 5-95%.

Darren

 

[ckchew666]

Thanks for all the replies, after searching around, I've found 2 brands of humidity transmitter. I just need humidity as for temperature I can use thermocouple to PLC thermocouple module.

From RENSE
http://www.rense.nl/rense.nl/RI_nl/low_cost_e.html
Model: Humidity & Temperature mA Transmitter 787

From Cole Palmer
http://www.coleparmer.com/catalog/product_view.asp?sku=3730300
Model: EW-37303-00

1) I favour the RENSE due to lower cost, has anyone use this model before?

2) My intension is to wire the humidity transmitter directly into the PLC analog input module (4-20mA), i'm not sure if either of these module (mentioned 4-20mA output) is suitable for my application. PLC just need the reading from humidity transmitter for monitoring only + display at HMI.
Appreciate your advise. Thanks a lot.

 

[Sheldn]

I have always had good luck with Vaisala http://www.vaisala.com/
The product uses a capacatance technology. This would work well in an indoor application where the humidity did not decrease quickly.

Heated mirror type humidity would be recommended for applications where humidity decreases quickly and you need to respond.

 

[nurhan yucel]

Hi,
In my project I must use temperature and humidity sensor. These sensors should be appropriate for s7 1200 v4.0. Can you help me? I couldn't decide on sensors.

 

[Racer5039]

This may help as a source. I have used them in building automation projects.
http://www.kele.com/humidity-home.aspx