How to Troubleshoot Electrical Noise Interfering with Proportional Valve Control Signals

Electrical noise can disrupt proportional valve control signals, leading to unstable motion, drifting, or inconsistent response. Because these valves rely on precise electrical input, even small interference can cause noticeable performance issues. A structured troubleshooting approach helps pinpoint and eliminate the source.

Check Grounding and Bonding First

Poor grounding is one of the most common causes of electrical noise. Ensure the controller, power supply, valve driver, and machine frame share a solid, common ground. Loose or floating grounds can introduce signal fluctuations that appear as valve instability.

Use Shielded Cables and Proper Routing

Control signal cables should be shielded and routed away from high-power lines, motors, inverters, and solenoids. Running signal and power cables in parallel over long distances increases electromagnetic interference. If crossing is unavoidable, cross at right angles to reduce coupling.

Inspect Power Supply Quality

Unstable or noisy power supplies can inject ripple into control signals. Check for voltage fluctuations under load and ensure the power source meets the valve driver’s specifications. Adding line filters or using regulated power supplies can improve signal stability.

Verify Connectors and Cable Integrity

Loose connectors, damaged insulation, or corroded terminals can act like antennas for noise. Secure all connections and replace worn cables. Even minor contact resistance changes can distort low-level control signals.

Separate Control and Power Grounds

Where possible, keep sensitive signal grounds separate from high-current return paths, then bond them at a single reference point. This reduces ground loops that commonly introduce noise into proportional valve drivers.

Confirm Controller Filtering and Signal Conditioning

Many controllers and valve drivers offer built-in filtering or smoothing options. Enabling appropriate filters can reduce high-frequency noise without slowing valve response. Avoid over-filtering, which can delay control signals.

Conclusion

Electrical noise affecting proportional valve control signals is usually linked to grounding, cabling, or power quality issues. By improving grounding, using shielded cables, separating signal and power paths, and stabilizing the power supply, control accuracy and valve stability can be restored.