Common Causes of Connector Corrosion and How to Prevent It

As you take your pick from the various connector solutions from RS such as industrial circular and heavy-duty connectors, terminal blocks, and splices, you will be mindful of a wide range of factors and risks that could come to pass. 

It will be necessary to evaluate such aspects as wire gauge, cable type, current, voltage, and the environment in which the given connector is to be used, as you seek to make the right choice for your project. 

However, another risk that cannot be ignored is that of connector corrosion. It is one of the most frequent causes of electrical failures, downtime, and maintenance costs. 

Despite this, many professionals and organisations charged with assembling, overseeing, and/or maintaining electrical and electronic systems aren’t as familiar with what leads to connector corrosion, and how they can prevent it, as they ought to be. 

A Quick Introduction to Connector Corrosion 

When an electrical connector is said to be corroded, this refers to a situation whereby the metal contact surfaces within such a device, and/or the outer housing, have become degraded. 

Connector corrosion happens as a result of moisture and contaminants interacting with the metal surfaces, or microscopic movement wearing away metal platings. 

If corrosion does set in with a particular connector, it can impair the device’s operation within a circuit. It can also cause damage to the locking mechanism and reduce the connector’s mechanical strength. 

5 Things That Bring About the Corrosion of Electrical Connectors 

Are signs of corrosion apparent on a connector you have just reached for? The chances are that one or several of these factors will be to blame: 

1. Moisture And Humidity Ingress 

High humidity levels are among the primary culprits for connector corrosion. In damp conditions, moisture can sometimes penetrate connector assemblies and react with exposed metal surfaces. This can create oxidation and drive down conductivity. 

Connectors can be especially vulnerable to such problems when used outdoors or in poorly ventilated environments. Connector corrosion often happens, for example, in outdoor, marine, or vehicle applications exposed to rain, mist, or washing. 

2. Environmental Contaminants 

The corrosion of electrical connectors can also be accelerated by such contaminants as salt, industrial pollutants, sulphur, acids, and dust. 

Salt, for instance, can find its way into connectors from sea air or winter road de-icing. It increases the conductivity of moisture and promotes electrochemical reactions, thereby furthering corrosion. 

3. Material And Galvanic Corrosion 

Dissimilar metals coming into contact with each other, such as copper with aluminium or steel, can create a galvanic cell in the presence of moisture. Poor plating or thin coatings can then wear away, exposing base metals. 

4. Poor Installation or Maintenance 

Water and contaminants can also get into connectors due to such factors as inadequate crimps, improper mating, deteriorated insulation, or flux residue from soldering. This can gradually lead to oxidation or “green” corrosion on copper. 

5. Fretting And Mechanical Wear 

Repeated mating cycles or vibration can be responsible for plating becoming worn down over time. As a consequence, fresh metal may be exposed to oxidation. 

Effective Prevention Strategies to Think About for Connector Corrosion 

Taking steps like these can go a long way to ensuring the connectors you use across your electrical installations aren’t beset by corrosion problems: 

1. Select Connectors Designed for The Given Environment 

The most effective preventative measure for connector corrosion is ensuring you only ever invest in connectors that match the intended operating environment. 

This is likely to mean choosing connectors that have a reputation of standing up well to water, humidity, chemicals, contaminants, vibration, and temperature extremes. 

2. Use Appropriate IP-Rated Connectors 

Ingress Protection (IP) ratings indicate a connector’s resistance to dust and water ingress. In the case of outdoor or washdown applications, selecting connectors with appropriate IP ratings can greatly minimise the risk of moisture-related corrosion. 

3. Choose Corrosion-Resistant Materials 

Depending on the application, engineers may seek to drive down the likelihood of corroded connectors by only placing their trust in the likes of stainless-steel components, nickel-plated contacts, and corrosion-resistant alloys. 

4. Put Into Action Regular Inspections and Maintenance 

Routine inspections, particularly when focused on areas like seals and gaskets, can help identify early signs of corrosion before critical failures have a chance to occur. 

5. Control Environmental Conditions 

Taking steps to control humidity and temperature can be important for reducing condensation and corrosion risks when it comes to indoor installations. 

Proven measures for this encompass the likes of ventilation systems, dehumidification equipment, environmental monitoring, and climate-controlled enclosures. 

Conclusion: Addressing The Risks to Your Connectors Will Be Vital for Success 

If corrosion is allowed to set in with the connectors used in your project or installation, this can have a range of perilous consequences. 

Such factors as moisture, salt exposure, chemicals, galvanic reactions, and mechanical wear can lead to heightened resistance, signal degradation, equipment failures, and costly downtime. 

The good news is that by selecting appropriate connector solutions, using suitable environmental protection ratings, and putting in place effective maintenance practices, you can help prevent connector corrosion from becoming a major problem.  This, in turn, can have greatly positive implications for the performance, reliability, and longevity of any electrical systems for which you are responsible.