Quasi-static charge amplifiers can accurately measure and amplify quasi-static physical quantity signals with extremely slow changes (as low as 0.1 Hz or even near direct current) from charge-output sensors such as piezoelectric sensors. A quasi-static charge amplifier is a precision instrument in engineering. It breaks through the limitations of traditional circuits, enabling piezoelectric sensors, which could originally only sense “dynamic changes”, to sense “nearly static” slow changes, greatly expanding the application scope of piezoelectric measurement technology.
Quasi-static charge amplifiers are mainly used in situations where long-term and high-precision monitoring of static or slowly changing physical quantities is required. The sensors equipped with them are usually piezoelectric sensors.
Long-term structural health monitoring
Monitor the slow settlement and stress relaxation of dams, bridges, and high-rise buildings.
Monitor the slow deformation of geological structures (such as mountains and mines).
Geophysics and earthquake research
Observe slow crustal strain, fault creep and other “slow earthquake” phenomena.
Monitor the long-term pressure accumulation before volcanic activity.
Precision manufacturing and testing
Measure the extremely slow deformation of machine tools or precision platforms under thermal effects.
Monitor the long-term creep characteristics of materials under constant load.
Scientific research
In materials science, measure the piezoelectric response of materials under extremely slow loading rates.
Conduct certain physical experiments that require long-term monitoring of small changes in force, pressure, or acceleration.
| Model | Channel | Measurement range (FS) | Quasi-static drift | Output voltage (FS) | Output current | Maximum zero error | Manuals |
| QEA 1000 | 1 (customizable) | +2 pC ~ 2.2 μC | ≤ 0.03 pC/s (@ 25°C) | ±10 V / ±5 V / ±2.5 V / ±2 V | ≤ 2 mA | ≤ 6 mV |
1. S. S. Sun, Y. Q. Chen, S.S Li, R. Y. Jia, A. L. Xiao, L. G. Tang, W. Y. Luo, Two-sample characterization of elastic and piezoelectric constants of piezoelectric materials via combination of ultrasonic pulse-echo,electric resonance,and hydrostatic piezoelectric constant measurements, Ceramics International, 51(30):62836-62843, 2025.