Grounding monitoring devices ensure that road tanker and tank wagons are electrostatically grounded correctly during the loading or unloading of flammable liquids. The device provides a conductive connection to the ground and monitors in parallel the quality of the electrostatic grounding. The electrostatic charge of the tank is kept on a safe level.
An occasional discharge in conjunction with a spark is prevented and therefore the explosion protection ensured.
The grounding monitoring device UZCL 3.d is able to distiguish
between the correct grounding of road tankers and the incorrect grounding of other items, e.g. tank platform. If the pliers are
connected to a road tanker the green light switched on and the
relay will be energized. The contacts of the relay can be used to control e.g. a valve or to trigger an alarm.

The following recommendations demand the grounding of tank
vehicles during the loading or unloading procedure and endorse that interlocks should be provided to prevent loading when the grounding cable is not connected.

• CENELEC CLC/TR 50404 Code of practice for the avoidance
  of hazards due to static electricity
• National Fire Protection Association NFPA77
  Recommended practice of static electricity 2000 edition

Zones 1 & 2