Topic: davis 7346.166 sensor

[johnd]

As far as I can see this is all pretty straightforward:

Look on the Sensirion website (www.sensirion.ch)  if you want the SHT3x specs.

The details of the new Davis sensors were copied in p1 of this thread about a week ago - all the available information is there. The specs tally IIRC from looking at the tech bulletin back in early January with the SHT31 being used, but I haven't seen any specific confirmation of this. The only public information AFAIK is a read across between the Davis and Sensirion specs but I seem to remember that this is fairly conclusive.

Edit: Apologies if anyone took this post to be more abrupt than I intended. All I was trying to say in summary was that I think that all the information that's likely to be available currently is already to hand eg in this thread and from Sensirion. The new sensor in the Rev AS ISS units is likely to be a significant step forwards from the previous .166 sensor.

[CW2274]

But not the 35.

[ValentineWeather]

But not the 35.

The SHT-35 was brought up during a phone conversation if I recall, correct? Maybe its so new and not in production yet.

[CW2274]

But not the 35.

The SHT-35 was brought up during a phone conversation if I recall, correct? Maybe its so new and not in production yet.

Yes. He said it would be released Q2 this year when we spoke about 2 months ago. I'll call again tomorrow; no sense in getting the 31 if the 35 is right around the corner.

[ValentineWeather]

 

[CW2274]

Just spoke to Sensirion. The 35 is due out around the end June, it will be the high end sensor so it will trump the 31, but he had no specs for me. Apparently those of use interested will just have to wait, but certainly should be worth it.

[ValentineWeather]

Sounds good thanks. The 31 doesn't look bad for now especially if the specs are true.

[CW2274]

Sounds good thanks. The 31 doesn't look bad for now especially if the specs are true.

Not at all. I especially like the flat humidity as dry as we get here.

[CW2274]

Sounds good thanks. The 31 doesn't look bad for now especially if the specs are true.

Not at all. I especially like the flat humidity as dry as we get here.

Ahmen! And, since dew-point is calculated from temp and humidity, that means our Tdew numbers will be more accurate, too.

[rwilhour]

Wish the SHT-15 price would drop (7346.174). Gives an idea just how much profit are in these parts.

Davis provided a drastic price drop in the 7346.166 and 7346.176 at the beginning of the year.  I stock my equipment because I don't like being at the mercy of a drop shipper.  The down side of keeping inventory hit me hard on these items... I had over 35 units of 7346.166 units in stock at the old wholesale price when the new wholesale price kicked in.  I complained to davis about the overpayment of the items I had in stock and they graciously refunded the price difference back to me.  On confirmation of the refund I immediately dropped the price of the 7346.166.  The price shown now is not a sale price but a new permanent price.

I am in the same condition with the 7346.176, I had many in stock when the price dropped; however, I was not given the price difference on these.  So while I dropped the price a bit on these, a larger price drop will be coming in the near future once I get some inventory at the new price.

[rwilhour]

All I have is what Ryan said. He may of been confused and said SHT-30. Being it says Hum. ±2% across entire range those are the 31 specs. We will know for sure when the new units come out and someone can actually look at one. The 31 is a step up like CW said for colder climates.

It is possible that I may have misspoke on this.  I have the new sensors in stock, if anyone cares I will put one under the microscope and take a peak to confirm what is under the hood.

[ValentineWeather]

All I have is what Ryan said. He may of been confused and said SHT-30. Being it says Hum. ±2% across entire range those are the 31 specs. We will know for sure when the new units come out and someone can actually look at one. The 31 is a step up like CW said for colder climates.

It is possible that I may have misspoke on this.  I have the new sensors in stock, if anyone cares I will put one under the microscope and take a peak to confirm what is under the hood.

You have a new one in stock? I would like to order one and I'm sure many do care. Looks like the 30 would be a step back with the humidity.
Ryan thanks for checking in on this.

[jerryg]

Ok guys i just got off the phone with Ryan and he had a few new in stock and i just ordered one to try out. The price is the same as the sht 11, 49.95.  I am really wanting to compare it to the humidity response on the high end compared to the sht15 i have. Will post back when i get it and run some side by side tests between the two.

[ValentineWeather]

I order couple for both stations. Hope he has enough in stock. 
These chips are super tiny so he hasn't been able to confirm which one it is even with magnify glass. He thought he saw a 30 but not positive and specs advertised say its the 31 so hoping.

[rwilhour]

I order couple for both stations. Hope he has enough in stock. 
These chips are super tiny so he hasn't been able to confirm which one it is even with magnify glass. He thought he saw a 30 but not positive and specs advertised say its the 31 so hoping.

I had three... now I have none...  Just ordered 25 more units and they should be here in 12 days.

[CW2274]

I order couple for both stations. Hope he has enough in stock. 
These chips are super tiny so he hasn't been able to confirm which one it is even with magnify glass. He thought he saw a 30 but not positive and specs advertised say its the 31 so hoping.

I had three... now I have none...  Just ordered 25 more units and they should be here in 12 days.

I guess I'm the only one who doesn't know which sensor you're talking about, and yes, I read above. Are you selling 30's or 31's?

[rwilhour]

I order couple for both stations. Hope he has enough in stock. 
These chips are super tiny so he hasn't been able to confirm which one it is even with magnify glass. He thought he saw a 30 but not positive and specs advertised say its the 31 so hoping.

I had three... now I have none...  Just ordered 25 more units and they should be here in 12 days.

I guess I'm the only one who doesn't know which sensor you're talking about, and yes, I read above. Are you selling 30's or 31's?

That is a darn good question and I really don't know positively the answer to that yet.  I will put one under a microscope this evening and see if I can find out.  In the mean time will will ask Davis and see if I can get some info.

[CW2274]

 

I order couple for both stations. Hope he has enough in stock. 
These chips are super tiny so he hasn't been able to confirm which one it is even with magnify glass. He thought he saw a 30 but not positive and specs advertised say its the 31 so hoping.

I had three... now I have none...  Just ordered 25 more units and they should be here in 12 days.

I guess I'm the only one who doesn't know which sensor you're talking about, and yes, I read above. Are you selling 30's or 31's?

That is a darn good question and I really don't know positively the answer to that yet.  I will put one under a microscope this evening and see if I can find out.  In the mean time will will ask Davis and see if I can get some info.

[ValentineWeather]

Specs on Davis bulletin point toward SHT-31. It clearly states humidity range ±2% across entire range. So if I was a betting man I say its the 31.  The SHT-30 is  ±3% across narrower range.

Accuracy Specification
The new Temperature Humidity sensor is much more accurate than the prior sensor.
 
New Temperature Humidity sensor spec
Temperature
·         ±0.3°C (±0.5°F) across entire range
Humidity
·         ±2% across entire range
 

[CW2274]

Thanks. My 15's only 2 years old so I'll be waiting for the 35 unless that falls through.

[ValentineWeather]

Thanks. My 15's only 2 years old so I'll be waiting for the 35 unless that falls through.

You would especially benefit with tighter 31 specs on low humidity. I will benefit also but mainly winter temperatures which live well below 0 C. Plus I find the sht-15 has higher error than advertised specs for humidity, more like ±5% so hoping this new style chip tightens that up.

[CW2274]

Thanks. My 15's only 2 years old so I'll be waiting for the 35 unless that falls through.

You would especially benefit with tighter 31 specs on low humidity. I will benefit also but mainly winter temperatures which live well below 0 C. Plus I find the sht-15 has higher error than advertised specs for humidity, more like ±5% so hoping this new style chip tightens that up.

Oh, no doubt. If the 35 wasn't directly around the corner, I'd be all over the 31 like ham on a hobo samich. May still do it.....

[CW2274]

Thanks. My 15's only 2 years old so I'll be waiting for the 35 unless that falls through.

You would especially benefit with tighter 31 specs on low humidity. I will benefit also but mainly winter temperatures which live well below 0 C. Plus I find the sht-15 has higher error than advertised specs for humidity, more like ±5% so hoping this new style chip tightens that up.

I've found the 15's humidity quite accurate. I've been down to 7% today with the intl' airport and the AFB both at 6%.

[ValentineWeather]

Maybe I just have bad luck with chips. Even using Cumulus offset I can slope 2% out linearly but still run +2-3% over a large range.

[CW2274]

Maybe I just have bad luck with chips. Even using Cumulus offset I can slope 2% out linearly but still run +2-3% over a large range.

One thing I've noticed that in most conditions, my dewpoint tends to remain very consistent all day long, while both airports it goes up and down like a yo-yo.