Cumulus Support

My VP2 temp/hum sensor is failing again (sporadic high temps, humidity too low). This one has lasted three years, so that's an improvement on the previous ones, which typically lasted between 9 and 18 months.

I'm wondering what my options are for replacing it at less cost than the official part - I believe some of you have used third-party replacement boards, or repaired it using replacement chips? Any good suggestions? I'm semi-retired now, so I have to make savings where I can

I replaced mine with a SHT-75 mini board. It is a direct wire-wire replacement for the Davis board - though you have to solder it on. I then encased to solder joints and mini-board (apart from the sensor chip itself) in epoxy. It is very small and the existing wire clip is fine for holding it place. To protect the sensor I placed mine in a tiny 'bag' made from some of my daughters old tights!

For you I think the key thing is finding a suitable enclosure for the sensor to keep the salt out. The Davis sensor enclosure on their boards is useless for this, it is just a wire mesh. The Sensirion supplied cover is of a permeable membrane type (think Goretex type stuff) - far superior.

I think Belfryboy offers a board with the Sensirion sensor cover, but I could be wrong.

Thanks, Mark. I'm happy to do soldering, but I think maybe I'll investigate Belfryboy's ready-built solution, if he's still doing them.

Hi,

mcrossley wrote:The Sensiorion supplied cover is of a permeable membrane type (think Goretex type stuff) - far superior.

Is that supplied with a "real" SHT-75 sensor or an "optional extra" - I can't find any reference to it?

FWIW, the "best price" I've found (in a brief Google) for a Sensirion SHT-75 from a "well-known" supplier is £23.60 from CPC-Farnell plus VAT, but shipping should be free (Royal Mail) even to the Northen Isles? RS and even the main Farnell site seem somewhat more expensive.

Cheers, Alan.

The Sensirion covers are made for the SHT1x sensors http://www.sensirion.com/en/products/hu ... for-sht1x/

You are on your own for the SHT7x boards.

That seems like a reasonable price.

I see they are releasing a SHT3x series, wonder what the pricing on those will be like, and how compatible with the ISS they will be - they are dual I2C and voltage outputs.

Hi,

Thanks, that's very interesting. The covers seem surprisingly cheap (for the application), less than £3 from ebay.co.uk , a little over from CPC and significantly less from RS, etc..

Cheers, Alan.

steve wrote:.....but I think maybe I'll investigate Belfryboy's ready-built solution, if he's still doing them.

Had mine for over a year now without problem.