July 26, 2011
What is a thermocouple sensor?
A thermocouple is a sensor for measuring temperature. It consists of two dissimilar metals, joined together at one end. When the junction of the two metals is heated or cooled a voltage is produced that can be correlated back to the temperature. The thermocouple alloys are commonly available as wire.
What are the different thermocouple types?
A thermocouple is available in different combinations of metals or calibrations. The four most common calibrations are J, K, T and E. There are high temperature calibrations R, S, C and GB. Each calibration has a different temperature range and environment, although the maximum temperature varies with the diameter of the wire used in the thermocouple. Although the thermocouple calibration dictates the temperature range, the maximum range is also limited by the diameter of the thermocouple wire. That is, a very thin thermocouple may not reach the full temperature range. Click here to view a complete reference table for each thermocouple. The table includes international color codes for thermocouple alloys, temperature range and limits of error for almost every kind of thermocouple.
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July 24, 2011
The air conditioning of the office premises is based on a 4-pipe system produced by Wesper, a worldwide manufacturer. The air conditioning system functions on the “chiller-“fan-coil”- conditioner” principle that is used for the following types of space:
- Office premises
- Commercial premises
- Administration premises, utility service rooms, dispatcher room, server room and room of boiler operator
- Halls and vestibules
The sources of cold are chillers, the two low-noise cooling machines manufactured by York (Great Britain), with productivity of 783 kW each, which works only on cooling. The fan-coils are channel-type conditioners embedded in the suspended ceilings in all the air conditioned premises. All pipes conducting cold to the fan-coils have heat insulators. In addition, to reduce the noise produced by the ventilation and refrigeration systems, special measures like having a resiliently supported base, sound insulation and sound dumpers have been taken.
The parameters of the air conditioning system are designed to provide comfort, namely:
- 24-hour air conditioning maintaining comfortable microclimate parameters by using the combined supply and exhaust ventilation, with input air heating up to +18°С and humidification to 45% in the winter and cooling down to +20°С in the summer.
- Further air temperature adjustment to comfortable parameters in each separate office is made through 4-pipe fan-coils with individual-zoned settings.
Recuperation sections of the combined supply-and-exhaust ventilation system help keep energy consumption low.