The display accuracy of digital pressure gauge

Digital pressure gauges (including pressure calibrators and digital pressure gauges) are calculated according to the full scale (FS%). The tolerance calculation formula for digital pressure gauges of 0.05 grade (-100 ~ 200) kPa is this:
± (upper limit value-lower limit value) * Accuracy% = ± 300 * 0.05% = ± 0.15kPa, that is, the allowable error of each calibration point is ± 0.15kPa.
The display accuracy of digital pressure gauges generally meets the tolerance requirements. For example, (-100 ~ 200) kPa digital pressure gauge, the accuracy is 0.05, the allowable error is ± 0.15kPa, then when the unit is kPa, you need to be able to distinguish 0.01kPa pressure, you need to display 3 integers, 2 decimals , A total of 5 digits.
Accuracy level 0.05 digital pressure gauge is mainly for the full range, that is, the allowable error in the entire range is consistent, which is essentially different from the level 0.05 piston pressure gauge. Some units on the market take the reading accuracy plus full-scale error as the standard. Such an error is actually the sum of the reading error and the full-scale error, which is much larger than the simple allowable error.
Some digital tables are error representation methods, such as ± (0.05% RD + 0.05% FS), the allowable error is 0.1, and the allowable error is much larger than the 0.05% FS digital table.
For example ± (0.05% RD + 0.05% FS), -100kPa-200kPa digital pressure gauge, at the calibration point of 200kPa, the tolerance is ± (0.05% * 200 + 0.05% * 300) kPa = ± 0.25kPa It is about twice as large as the actual allowable error of 0.15kPa from 0.05 to 100kPa-200kPa.