Topic: Davis 6834 Sensor

[twcmaster]

I was surprised to see there wasn't more chatter about this when the new catalog came out. Has anyone gotten their hands on one yet or have any thoughts or even speculation on if there are any changes versus a standard "outdoor" sht-31?

[johnd]

Actually, 6834 has been mentioned in a recent thread here somewhere. But I'm not sure why there should be much chatter - as far as I'm aware it's just a standard SHT31, exactly as used in the standard ISS, but effectively minus the radiation shield. So there's not really anything new about it other than the lack of shield and a different mounting case.

The reason for its introduction is the pending launch of the Weatherlink Live unit which will make it significantly easier to run multiple transmitters. One application could well be to have T/H transmitters in several rooms in a house for which the old 6382 transmitter with its shield etc was unnecessarily large and costly. A 6332** (or 6331) Wireless Sensor Transmitter + 6834 is a neater and more cost-effective solution.

**What was previously known as the Anemometer Transmitter, but which always has been able to accept multiple sensors.

[twcmaster]

Ok, thank you for the info!

[CW7491]

johnd or anyone who has knowledge on this, is it your understanding that this 6834 sensor/part number will also be used in the ISS as an outdoor sensor to replace the 7346 series (7346.070) or is this intended to be an indoor sensor only?

[CW2274]

As pictured on Davis's site, it'll be indoor only, the base is completely unnecessary/unwanted for fitment inside the ISS sensor chamber. I'm curious why it's assumed to be an SHT31, I see no docs saying so.

[johnd]

As pictured on Davis's site, it'll be indoor only, the base is completely unnecessary/unwanted for fitment inside the ISS sensor chamber.

Or I guess it could be used outdoors inside eg a traditional Stevenson screen. But where did the idea come from that it might replace the existing T/H sensor in the ISS - AFAIK it IS the same sensor, other than a different mounting base.

I'm curious why it's assumed to be an SHT31, I see no docs saying so.

Occam's razor - it's the simplest assumption. If you have a production process making many thousands of T/H PCBA's a year that only use SHT31 and you also need the 6834 to interface to a regular VP2 transmitter then why would you use anything else? But yes you're right - I'm not aware of any explicit confirmation that the sensor element is SHT31.

[CW2274]

As pictured on Davis's site, it'll be indoor only, the base is completely unnecessary/unwanted for fitment inside the ISS sensor chamber.

Occam's razor - it's the simplest assumption. If you have a production process making many thousands of T/H PCBA's a year that only use SHT31 and you also need the 6834 to interface to a regular VP2 transmitter then why would you use anything else? But yes you're right - I'm not aware of any explicit confirmation that the sensor element is SHT31.

Yes, completely agree. With that, I'm wondering if newly produced VP2 and Vue consoles are still internally housing SHT11's? So along this line of thought, if so, why? PCB differences?

[johnd]

Yes, completely agree. With that, I'm wondering if newly produced VP2 and Vue consoles are still internally housing SHT11's? So along this line of thought, if so, why? PCB differences?

I don't know for sure about the consoles - they fail so rarely that I can't remember the last time we needed to take a recent console apart. Maybe the T/H spec might give a clue.

But it wouldn't surprise me if SHT11 was still being used if there was even a small price advantage to doing so. Given the extra heat generation (with logger) inside the console and lack of free ventilation, it's not as if an improved T/H spec would ever be noticed by the user.

[CW2274]

Yes, a 31 inside would certainly be overkill (I'm sure there's some who'll say that's for the outside too ). I suppose 11's are still available.