Regular calibration and fault diagnosis of SF6 gas density monitoring devices are crucial for ensuring the reliable operation of gas-insulated equipment.However

existing calibration instruments often suffer from cumbersome operation

low portability

and limited measurement accuracy

which slow down operation and maintenance(O&M)efficiency and may cause misjudgments due to calibration deviations

thereby hindering the advancement of intelligent O&M.To address these issues

this paper presents a handheld SF6 gas density tester with an accuracy within ±1% FS was developed based on the measurement principles and characterization methods of SF6 gas density

and combined with a high-performance hardware platform and a software algorithm

which optimizes analytical equations using the fixed-point principle.A dedicated test platform was established to evaluate key performance indicators such as measurement accuracy and environmental adaptability.Field tests verify that the tester features flexible interfaces and enables rapid calibration of SF6 gas density monitoring devices while accurately locates faults.The proposed tester effectively addresses operational challenges in on-site maintenance and calibration

improves O&M efficiency

and provides technical support for the efficient operation of high-voltage gas-insulated equipment.