Grounding Detector Unit is an electronic device which ensures safe & reliable grounding of generated electrostatic charges during loading or unloading operations of inflammable hydrocarbon products. The unit gives a local visual indication for proper grounding & transmits the signal to a remote loading control automation system.Download Literature in pdf format.

DESIGN FEATURES

• Local visual indication for proper or improper grounding.
• Ensure minimum capacitance & resistance of vehicle to ground.
• Zener barrier protected grounding loop for additional safety.
• Remote signal to loading control system.
• Internal heater ensures satisfactory performance in extreme cold, rain & damp weather conditions.
• Special rugged clamp for connection to vehicle.

PRINCIPLES OF OPERATION

While loading & unloading of inflammable hydrocarbon liquids it is required to maintain an equal potential between the filling structure & the vehicle tank in order to avoid spark hazard due to electrostatic charges. The grounding detector consists of an electronic circuit housed in a flameproof enclosure. A special crocodile clamp made of anti-spark material connected wit an abrasion & oil resistant cable connects the unit to the vehicle. Green & red lamp placed in a glass window show a proper or improper grounding condition. Potential free relay contact outputs from the unit are connected via a cable to the remote control system. When the grounding clamp of the unit is connected to the metal surface of the vehicle the device checks the capacitance & resistance of the vehicle towards the earth. The internal grounding loop resistance is reduced to less than 1 ohm ensuring perfect grounding of the vehicle. At the same time the red lamp switches over to green signifying proper grounding & internal relay is actuated to give potential free contact outputs to the remote control system. The vehicle grounding loop is zener barrier protected for added safety. In case of a break in the grounding loop during loading operation the unit de-activates the relay signaling the remote control system to stop operation in order to avoid hazard.

An internal heater in the form of resistance is provided to emit enough heat in order to maintain the internal housing temperature to 30o C to ensure proper functioning in adverse climatic conditions such as extreme cold, rain & damp weather. The electronic circuit of the unit is designed to detect abnormal conditions such as clamp connected to parts already grounded or the clamp connected to insulated surfaces.

APPLICATIONS

• Fuelling & de-fuelling of liquid hydrocarbons in the Tank Truck / Rail Wagons / Ships.