How Smart Electrostatic Grounding Helps you Avoid Risks

When sparks are flying, that is not necessarily a good thing. In industry, uncontrolled electric discharges are one of the most frequent causes of explosions and fires. Long-term studies have shown that they are the third-ranking hazard source when combustible substances are moved. These include mineral oil products, disinfectants, adhesives or solvent-based paints and varnishes in filling plants, paint stores and print shops.

What can we do for you?

The most frequent causes for explosions of combustible media

Spontaneous combustion
Overheating of moving parts
Electrostatic discharge sparks

"Usually there are no
problems during grounding!"

"Nothing bad has
happened so far"

"You can count on me, boss.
I always ground correctly"

Don't make the mistake of relying on such statements! The sources of error in electrostatic grounding are often not visible to the naked eye. Incorrect grounding attempts often give production employees a false sense of security. Tragically so, because this increases the risk of an explosion or fire.

One example: In practice, barrels and containers such as BigBags or tank trucks are frequently found to have well-intentioned but faulty grounding. For example, unsuitable tools such as battery clamps or welding guns are used. Thus the users have no chance to check if the contactor is able to pierce through paint or a layer of dirt, if the cable has an internal break or if a grounding point is really connected to potential equalization.

Six common mistakes to avoid during electrostatic grounding

Fastening the grounding tool to the wrong place on the vessel – for example, to the insulated plastic shell instead of directly to the metal tank.

Using an old or defective clamp, thus preventing the contact from being made.

Attaching the clamp to a dirty location on the metal tank.

Using a defective cable between the clamp and the grounding point – with the defect often being inside the cable and thus not visible.

Using a ground contact with insufficient ground or none at all despite the marking.

Using a clamp with insufficient clamping force. The pressure drops during the transferring process.

Don't wait until the case of damage has occurred. Act now! Using an Eltex ground monitoring system eliminates all of these potential hazard sources.

Why is electrostatic grounding so important?

Electrostatic energy occurs when solid or liquid surfaces rub against each other. For example, when pumping non-conducive explosive media through a pipeline. Ions of one potential are deposited on the vessel/inside pipe wall, while ions of the opposite potential are diffusely distributed in the medium being moved.

As a result of the movement, the charge carriers on the tube are separated from those in the liquid. The latter becomes charged - and when it flows out of the pipe, it releases the charge uncontrollably into the collection container. If this container is not grounded, it acquires an electrostatic charge. If you then move this container close to grounded machine part, there will be a sudden flow of charge. The resulting discharge spark can ignite the existing gas/air mixture and thus cause a fire or explosion.

It is imperative to avoid this effect and the risk it incurs.

Three industries, three examples. How to ensure smart grounding

Container grounding in filling plants

The Problem ...

At filling plants, highly flammable liquids such as solvents, cleaning agents, petroleum products or even powdery media such as flour, sugar, powder, are delivered by tanker and silo vehicles, in large containers (IBC), drums or in BigBags.
When delivering media in tanker or silo vehicles, electrostatic grounding systems are often already in use so that, when the vehicles are emptied, no
uncontrolled electrostatic discharge sparks arise.

When these media are now pumped into corresponding tanks for the filling plants, the situation is different in many cases.
Frequently, extremely simple ground clamps are used without monitoring the connection. This involves the great risk that non-conductive earth connections will not be detected, such as those caused by defective clamps or cables or by impenetrable insulating contamination at the contact points of the earthing clamps. In a worst-case scenario, this can cause a fire or explosion due to an electrostatic discharge spark.
The Solution ...
All conductive or dissipative containers greater than five liters in volume must be grounded and should be monitored. To provide maximum assurance, use ground monitoring systems from Eltex here. They offer safe and continuously monitored grounding that, depending on the model, includes integrated output contacts for process enabling.
- Smart grounding with Eltex
  
  Grounding of an IBC
  
  Grounding for fuel delivery
  
  TERRABOX

Ground Monitoring in Paint Shops

The Problem ...

Electrostatic charges are created when refilling paints and solvents and when blending these components. The only way to prevent this is by grounding both the paint container/mixing container and the pump/mixer. Especially when handling paints, there is a high risk that one of the containers will become contaminated with dried paint that adheres to it with an insulating effect. If an unsuitable ground clamp is now attached, it is entirely possible that it will not be able to penetrate the paint layer, thus causing the container to not be grounded. The user has no control whatsoever unless they remeasure the resistance to ground during each grounding procedure. Generally, though, few users bother to do this. The lack of grounding can result in an electrostatic discharge spark, igniting the existing "solvent cloud" and causing massive injury and property damage.
The Solution ...
Using a grounding system enables you to identify any unsafe ground and/or monitor the presence of a safe connection for the long term.The Eltex TERRALIGHT makes this possible without major installation effort. The battery-operated ground monitoring device, in combination with the TERRACLAMP ground clamp, offers an optimal system for safe and permanently monitored grounding in these kinds of manual transfer or mixing processes. If connected and handled correctly, incorrect grounding is no longer possible. After connecting the ground clamp, the user obtains corresponding feedback immediately via the signal lamp on the TERRALIGHT. With a corresponding version of the TERRACLAMP, the user can even see directly on the ground clamp whether the grounding operation was successful.
- Smart grounding with Eltex
  
  Industrial painting
  
  Mixing and decanting of paints/lacquers
  
  TERRALIGHT

Ground Monitoring in Gravure Print Shops

The Problem ...

When delivering solvents and inks using tankers and when transferring inks and solvents from IBCs and barrels to smaller containers, all conductive tanks have to be grounded to prevent electrostatic charging. In many cases, this is done with a simple clamp connected to a presumably conductive grounding point. However, the user cannot tell if a potential equalization has actually occurred as a result of applying the ground clamp to the object being grounded. However, if taking this measure does not ensure grounding of the object, this incurs the risk that electrostatic discharge sparks will trigger a fire or explosion.
The Solution ...
All portable conductive or dissipative containers that are brought into an Ex area must be grounded and should be monitored. However, only ground monitoring offers maximum safety here. The ideal solution for ensuring safe grounding and keeping the maintenance and testing effort down to a minimum is the battery-operated TERRALIGHT grounding unit from Eltex. Along with the TERRACLAMP, this grounding system provides maximum protection against unwanted electrostatic discharges and their consequences. Another advantage of the system is that the user can see immediately whether a ground connection is present by means of a signal light.
- Smart grounding with Eltex
  
  Passive grounding of paint container
  
  Mobile grounding at pump station
  
  TERRALIGHT

Our expert will be pleased to advise you on electrostatic grounding

Walter Schwarzwälder, Sales Manager Grounding: "Electrostatic energy is the third largest explosion hazard in industry. Controlling it protects production employees – and is much cheaper than fixing damage. In real-life applications, we often see inadequate attempts at grounding. We would be glad to provide advice or carry out an on-site assessment of your production system."

More information about Eltex grounding products:

Eltex Products GROUNDING