| Specification | 
		
		
			| Measuring function | 
			llumination and temperature, difference value,max value,  
			min value of illumination | 
		
		
			| Main parts of photomet- er head | 
			Photodiode+cosines corrector+correction filter | 
		
		
			| Temperature  probe | 
			NTC thermistor | 
		
		
			 
			Iluminance 
			measuring range | 
			Total measuring range:0~200,000 Lux,into four ranges 
			×1:0~199.9 Lux 
			×10:200~1999.9Lux 
			×100:2000~19999.9Lux 
			×1000:20000~200000Lux | 
		
		
			Temperature 
			measuring range | 
			-9.9℃~49.9°℃ | 
		
		
			Iluminance 
			accuracy | 
			±3%rdg(below  10000  Lux) | 
		
		
			| ±4%rdg(above  10000  Lux) | 
		
		
			| Temperature  accuracy | 
			±1.0℃ | 
		
		
			 
			Units of illuminance 
			and  temperature | 
			Four combinations of units are available | 
		
		
			| Lux/℃ | 
		
		
			| Lux/°F | 
		
		
			| FC/℃ | 
		
		
			| FC/°F | 
		
		
			 
			Storage of illumination data | 
			Automatic 
			storage | 
			Max number of data groups is 1000,and storage  
			cycle is set by APP(WT81B) | 
		
		
			Manual 
			storage | 
			Max number of data groups is 67,and  whether to  
			store data is deceived by manual operation. | 
		
		
			| Operating temperature/ humidity | 
			0~40°℃,10~90%RH | 
		
		
			Storage temperature/ 
			humidity | 
			-10~50℃,10~90%RH | 
		
		
			| LCD screen update | 
			2 times/s | 
		
		
			| Power source | 
			3* 1.5VAAA batteries |