Maintaining the correct pre-charge pressure (p₀) in hydraulic accumulators is critical to ensuring reliability, efficiency, and safety in hydraulic systems. A drop in pre-charge pressure can compromise performance, damage components, and lead to costly downtime. To address this, HYDAC offers a range of intelligent monitoring products designed specifically for continuous and accurate supervision of accumulator health.

 HYDAC Monitoring Solutions

• P₀-Guard (EDS 3400 series) The EDS 3400 enables the accumulator pre-charge pressure (p0 ) to be monitored and the accumulator charging function to be controlled. The accumulator’s pre-charge pressure is monitored on the fluid side during each shutdown process (when the fluid side of the  accumulator is discharged). 

• HYDAC Bladder Integrity System The BIS operates on the gas side of the bladder accumulator. It detects when fluid has entered the bladder and triggers a signal. This makes it possible to detect bladder  breakage. Temperature and pressure can also be recorded via electronics (current loop/ HART).

• Piston position monitoring The laser linear position measurement system visually monitors the piston position and is mounted on the gas side. Its functional principle is based on elapsed time measurement. This involves the laser beam reaching the piston, being reflected and then being  detected by the sensor. The position of the piston in the piston accumulator is calculated  on the basis of the time the laser beam takes to complete its journey.

• Piston position monitoring The HLT is a linear, magnetostrictive position measurement system. Its functional  principle is based on elapsed time measurement of current and torsion impulses which are exchanged inductively without contact between the measuring point (= piston position) and the electronics.

Benefits at a Glance

1. Early detection of pre-charge pressure loss

2. Increased system availability and efficiency

3. Predictive maintenance instead of reactive repairs

4. Easy integration into digital monitoring networks

HYDAC’s pressure monitoring range goes beyond simple measurement—it provides intelligent, connected solutions that safeguard hydraulic accumulators and extend system lifetime.