Downgrade the use of calibration or incomplete use of the yellow logo, such as multimeter only test resistance, do not test other parameters. Calibration certificate should also use the yellow logo, calibration certificate generally have 2 kinds, one is not qualified to have the ability to produce calibration certificate. The other is the instrument is too poor, calibration data to be corrected.
Disabled or unqualified equipment with a red logo, deactivated equipment after the start, you can post the corresponding logo (green or yellow) according to the situation.