Media Center

Proper design-based valve and actuator operation is a key factor for the safe and reliably operation of nuclear power plants. According to the World Association of Nuclear Operators, valve issues are the leading cause of forced plant outages. Valve repairs can be expensive, especially for contaminated valves, and the availability of long lead time spare parts or obsolete parts can cause difficulties. To mitigate the number of valve issues, significant efforts have been undertaken to implement predictive maintenance concepts based on costly and intensive recurrent in-situ testing of the valves and drives.

The application of the valve and drive online monitoring and diagnostic system ADAM / SIPLUG supports safe and reliable plant operation and paves the way to a cost-effective condition-based maintenance strategy implementation. A SIPLUG module, permanently installed in the motor control cabinet (MCC), is able to record different electric values like active power or switch signals, during the normal operation of the assigned valve. The SIPLUG module is designed for installation in the cable outlet area or inside a feeder of a switchboard. SIPLUG consists of a compact sensor module and a put-on controller module on top.

Using the 64-bit software ADAM, each valve operation is automatically evaluated and assessed. Especially for safety-related and operation-related valves this provides valuable information on component condition to ensure proper function and contribute to optimization of maintenance strategies as well as effective maintenance execution.

For monitoring of solenoid valves (SOV) another type of SIPLUG sensor is available which supports the assessment of the dynamic and electrical behavior of SOV by measurement of voltage and current.

SIPLUG is qualified according to IEEE and KTA (1E separation, seismic integrity, high voltage, EMC, radiation and climate).

Your Benefits

Usage of the ADAM / SIPLUG technology allows:

  • Continuous verification of functional behavior of valves and actuators during normal operation of the plant
  • Optimized outage times based on knowledge of the current valve and actuator condition
  • Early detection of changes or irregularities in functional behavior
  • Allows post-fault analyzing – if something happens, it is recorded
  • Reduced maintenance costs (cost savings per testing and valve of about € 5,000) and minimization of personnel dose rate



Western Europe

  • Finland (EPR reactor)
  • Belgium (PWR)
  • Netherlands (PWR)
  • Spain (BWR)
  • Switzerland (PWR)
  • Germany (PWR and BWR)


South America

  • Brazil (PWR)
  • Argentina (PWR)


Eastern Europe and Russia

  • Russia (RMBK)
  • Bulgaria  (VVER)
  • Hungary (VVER)



•  China (EPR reactor)


PWR: pressurized water reactor
BWR: boiling water reactor
VVER: water-water power reactor
RMBK: high power channel-type reactor

Interested in Valve and Drive Online Monitoring and Diagnostics – ADAM and SIPLUG?


Maintenance management for nuclear power plant: Integrated valve maintenance


Maintenance optimization – predictive vs. preventive maintenance

CANDU Reactors VVER Reactors CANDO VVER Westinghouse