Bimetallic thermometer allowed error is how to calculate? Accurate level 1 range 0 to 150. 5

In industrial measurement, the accuracy of the often said with a precision instrument, precision is the maximum error of the reference to remove & other; ± ” Number and & other; %” Number. Precision measuring instrument is one of the important indicators of quality, our country industrial instruments into 0. 1, 0. 2, 0. 5, 1. 0, 1. 5, 2. 5, 5. 0 seven grades, and logo on the meter scale or nameplate. Accuracy level customarily called precision level. Bimetallic thermometer precision grade based on its permissible error of the dial scale value by it's percentage, its accuracy level the greater the number of permissible error of dial scale limit value is larger. Range, the greater the same precision level, it measured the absolute value of the temperature the greater the margin of error. 1. Level 5 and 1. Level 0 respectively under normal use, the the permissible error of the thermometer was range & plusmn; 1. 5 and & plusmn; 1. 0%. So the range is 0 ~ 150 ℃, permissible error for & plusmn; 2. 25℃。