This slim, rugged and watertight sensor was specially designed for installation in closed cabinets, like refrigerators and freezers, with special requirements about hygiene. Device can be used for monitoring temperature in refrigerators, cold food storage, drug storage and similar places with special thermal requirements. Product resistive to water droplets, most of antiseptics, icing and freezing.

Nowadays, there are many many kinds of temperature sensors available on the market.  For example, popular Dallas (maxim)  sensor DS18B20 provides guaranteed accuracy not worse then half of degree and have 12 bit resolution, that translates into 0.1ºC granularity of readout. But, one small detail makes sometimes big troubles: it is wire, that connect sensor to data logger, alarm device or regulator. If we speaking about cabinets with controlled internal environment – refrigerators, freezers, dryers, egg incubators, etc – all of them must be tightly closed during their operation, so guiding of any additional wire always became a problem. Especially if we cannot or don’t want to drill anything. We offer universal solution for many application – combination of excellent temperature sensor DS18B20 with wireless data transmission circuit in small hermetically glued enclosure, capable work well for years without any maintenance in dry or wet, hot or subzero cold environments with presence vapors of alcohol, formalin and other antiseptics.

On the picture sensor shown in black color enclosure, but production items also available in white color.

Technical specifications:

• Temperature range: -25 to +85 ºC (Limited by power source)
• Temperature transducer: DS18B20 (Made by Maxim, USA)
• Accuracy: better then ±0.5ºC in all range (according to transducer datasheet)
• Readout granularity:  ±0.1ºC in all range (according to transducer datasheet)
• Operation frequency: 433.92MHz. Output power 1mW or 10mW in pulse ~10ms duration
• Outer size: 55 x 60 x 8 mm
• Mass: ~35 gramm
• Battery type: cold-resistive coin type lithium battery.
• Battery life: 1 to 7 years guaranteed, depend on programming (how often sensor will send signal and how much power will be applied to antenna):

Transmission interval (minutes)	Transmission range (meters) from metal fridge box	Battery life (guaranteed, years)	Battery life (expected, years)
1	10	3	3.5
1	50	1	1.2
3	10	5	6
3	50	2.5	3
5	10	7	8
5	50	5	6

When battery depleted or be near of end of the life, customer can simple exchange old sensor to new one just for cost of batteries and work to replace them.