1. Grounding System (Electrostatic Discharge Protection)
Why grounding is needed:
When you load or unload flammable liquids (like fuel, chemicals) into or from a railcar, friction can build up static electricity.
If not discharged properly, a spark could occur — causing a fire or explosion.
How grounding works:
A ground cable is physically attached from the loading terminal’s grounding and overfill protection system to the railcar.
The grounding and overfill protection system checks that the railcar is properly bonded to the earth (resistance usually <10 ohms).
Loading will not start (or is immediately stopped) if grounding is not confirmed.
Equipment used:
Ground verification clamps with sensors
Ground monitoring units with automatic interlocks
Alarms and status indicators (green = safe, red = unsafe)
2. Overfill Protection System
Why overfill protection is needed:
Overfilling a tank can cause dangerous spills, vapors, and even explosions.
How overfill protection works:
The railcar is equipped with sensors or probes (high-level sensors) inside its tank compartments.
When product levels approach maximum safe capacity, the sensor sends a signal via a wired connection or wireless link to the terminal’s overfill protection controller.
If the product level hits the limit:
Automatic shutdown of pumps/valves.
Audible and visual alarms trigger immediately.
Typical equipment:
Overfill probes (float type, capacitive, ultrasonic)
Electronic rack monitors
Emergency shutoff valves