Are there inexpensive small battery operated sensors that record and/or comunicate the internal conditions of a package, without opening them?

Some sensors would be in use for 12 mo. They would need to survive exposure to a acidic organic solid at ambient temperature. Data collected: relative humidity and temperature. One device preferred

Individual poling by ID would be nice but is not necessary if the transmission range is short.

Sensors would be placed in the middle of a 30 gallon fibre drum filled with the solids.

Thanks
Gary

 

There are several. The first I became aware of was Ball Datatrace... they helped HaagenDasz solve a mysterious bad taste problem back in the 1980s. It appears that the truckers were turning off their refrigeration units to save fuel, and then turning them on just before delivery. Of course the ice cream re-melted and re-froze. Datatrace put some sealed temperature dataloggers in specially marked packages of ice cream, and they started finding out what was happening. A number of other companies make these kinds of sensors today.

Best,

Walt Boyes
CONTROL magazine

Visit my blog at www.controlglobal.com

 

Temperature sensors are trivial. RH is less trivial but still reasonable. Short range RF is also trivial. Battery life can be acheived by not having continuous transmission. Having all of the above, off the shelf, to your specification, is unlikely.

Having such a device created may be an option. Only a few may be cost prohibitive. Many multiples becomes more affordable.

How many do you need?

Don DeWitt, PE
[email protected]
(my public address)

 

We offer inductive power and data coupling devices that can pass a measure sensor's value through air or non-ferrous material.