Dear Tristan,

How about measuring? (Specialist required with field experience)

Obviously, the steel cords are well insulated to earth.

Earthing (if possible) before working on the belt could solve the problem.

Induced voltage in a conductor occurs, when there is an (alternating) magnetic field existing or there is a moving conductor under an angle in a constant magnetic field.

External magnetic fields can occur when f.i. the 3 phases of the powersupply cable are loaded unequally.

Receiving an electric shock is a shocking experience indeed and must be prevented.

TAKE CARE

Teus ■

Dear Tristan,

How about measuring? (Specialist required with field experience)

Obviously, the steel cords are well insulated to earth.

Earthing (if possible) before working on the belt could solve the problem.

Induced voltage in a conductor occurs, when there is an (alternating) magnetic field existing or there is a moving conductor under an angle in a constant magnetic field.

External magnetic fields can occur when f.i. the 3 phases of the powersupply cable are loaded unequally.

Receiving an electric shock is a shocking experience indeed and must be prevented.

TAKE CARE

Teus ■

We practice grounding strap and rod to earth for the steel structure on steel cord and fabric belt installations. This is done when the belt parallels mega high voltage transmission from high above. We don't practice placing high voltage on the conveyor structure.

There is a calculation procedure to determine when and by how often this must be done. It is similar to lightening protection grounding.

Normally, the belt is covered with a metal sheet so the belt steel cords are electrically shielded. Fortunately, the maintenance personel do not experience your static buildup.

Coal field shiftable conveyors sometimes have such configurations. In this case, I believe you need to build a "special knife" that has a good grounding strap and rod which will disipate the induced charge to ground when the "special knife" is forced to contact the steel cords and before normal skiving is commenced. The skivers should wear insulating gloves when first establishing the grounding operation with the "special knife". ■

We practice grounding strap and rod to earth for the steel structure on steel cord and fabric belt installations. This is done when the belt parallels mega high voltage transmission from high above. We don't practice placing high voltage on the conveyor structure.

There is a calculation procedure to determine when and by how often this must be done. It is similar to lightening protection grounding.

Normally, the belt is covered with a metal sheet so the belt steel cords are electrically shielded. Fortunately, the maintenance personel do not experience your static buildup.

Coal field shiftable conveyors sometimes have such configurations. In this case, I believe you need to build a "special knife" that has a good grounding strap and rod which will disipate the induced charge to ground when the "special knife" is forced to contact the steel cords and before normal skiving is commenced. The skivers should wear insulating gloves when first establishing the grounding operation with the "special knife". ■

Dear Tristan,

I would tend to agree that the steel cords are obviously isolated. Assuming there is no ignition risk, the easiest solution is to ground the knives.

Herv Vaudrey

European Operations Executive

Chilworth

Email : hvaudrey@chilworth.fr

Web : www.chilworth.fr ■

Dear Tristan,

I would tend to agree that the steel cords are obviously isolated. Assuming there is no ignition risk, the easiest solution is to ground the knives.

Herv Vaudrey

European Operations Executive

Chilworth

Email : hvaudrey@chilworth.fr

Web : www.chilworth.fr ■