An oil and gas storage tank farm is not an ordinary electrical site. In a real tank farm, complex electrical connections and safety interlocking exist among tank bodies, pipelines, loading/unloading racks, pump areas, instrumentation systems, video surveillance, combustible gas detection, fire protection systems and power distribution systems.
What such scenarios truly need to solve is not "whether grounding exists", "whether SPDs are installed" or "whether test reports exist", but whether the grounding status is reliably maintained over the long term, whether static charges can be discharged stably, whether lightning strike and surge events are traceable, whether SPDs are still effective, whether the safety platform can alarm in time, and whether anyone reviews and handles the alarms afterwards.
GB 17681-2024, Technical Specification for Safety Monitoring of Major Hazard Installations for Hazardous Chemicals, has already pushed safety monitoring of major hazard installations from single-point equipment configuration toward system design, O&M and alarm management. For oil and gas storage tank farms, online grounding resistance monitoring and smart lightning protection systems should also be understood as a set of safety monitoring capabilities that can run, alarm, review and close the loop.
1. Before system design, identify the risk objects of the tank farm
An oil and gas storage tank farm must first identify its risk objects. Tank body grounding is one of the basic safety paths; attention is needed on the main grounding points of the tank body, auxiliary grounding points, tank-to-ground grid connections, equipotential bonding between tank bodies and pipelines and platforms, and whether the grounding status changes after a thunderstorm.
The loading/unloading area is a key area for electrostatic management. The tank truck grounding point, loading arm grounding point, static grounding clamp status, grounding confirmation before operations and grounding retention during operations all directly determine whether static charges can be discharged stably. This part is best interlocked with the operating workflow: operations are not recommended before grounding is confirmed, and operation abnormality should trigger reminders or interlock prompts.
Pump areas, process equipment, power distribution cabinets, instrument boxes, DCS/SIS/GDS-related instruments, video surveillance and communication equipment also need to be included in lightning protection and grounding status management. For these systems, power lines, signal lines, communication lines and instrument loops may all become surge intrusion paths.
2. How should online grounding resistance monitoring points be deployed?
A tank farm should not rely on a single "total grounding value". A more reasonable approach is to deploy monitoring points zone by zone around tank bodies, loading/unloading areas, pump areas, power distribution equipment and key nodes of the ground grid. This way the platform can determine which tank body grounding point has been high for a long time, which point mutates after a thunderstorm, and which zone is clearly abnormal compared with similar points.
For tank body grounding points, attention should be given to main grounding points, auxiliary grounding points, tank-to-ground grid connection points, equipotential bonding points and lightning protection down-conductor grounding points. For loading/unloading areas, attention should be given to tank truck grounding points, loading arm grounding points, static grounding clamp status, pre-operation confirmation and retention during operations. For pump areas and power distribution equipment, attention should be given to the local grounding status of motors, control cabinets, instrument boxes and power distribution cabinets.
The focus of online grounding resistance monitoring is not "displaying a nice number", but long-term trends, abnormal mutations, multi-point comparison, changes after lightning strikes and correlation with operating status. For large tank farms, these data reflect the real risks in the operation phase better than a single test report.
3. What subsystems should a smart lightning protection system include?
Smart lightning protection should not only record whether a lightning strike occurred. Lightning current and surge event monitoring should record, as far as possible, occurrence time, event location, peak intensity, polarity, waveform characteristics, duration, impulse energy and whether multiple strikes occurred. These data can provide a basis for incident review, equipment verification and risk grading.
SPD and surge protection monitoring cannot only look at disconnection telemetry. Instruments, communication, video, detection and control systems in tank farms may all be affected by surges, so attention should be given to SPD disconnection, leakage current, temperature, degradation trends, backup protection status, operation records and service life trends.
Static protection grounding monitoring should cover the loading/unloading workflow, including grounding confirmation before loading/unloading, grounding retention during operations, grounding clamp contact status, electrostatic discharge path, abnormal disconnection alarms and operation record retention. These data should ultimately all enter the safety monitoring platform, rather than being displayed in isolation on a local device.
4. How should the system architecture be designed?
The first layer is the field protection layer, including the air termination system, down conductors, grounding grid, equipotential bonding, SPDs, static protection grounding and explosion-proof field terminals. This layer solves the basic protection and discharge path problem and is the physical foundation of the system design.
The second layer is the status sensing layer, including online grounding resistance monitoring, lightning current monitoring, SPD status monitoring, static protection grounding monitoring, surge event recording and equipment alarm collection. This layer converts the previously invisible grounding, lightning protection, static protection and equipment status into data.
The third layer is the explosion-proof and communication layer. Oil and gas storage tank farms involve explosive hazardous atmospheres, so equipment selection must consider explosion protection type, temperature class, ingress protection rating, power supply method, communication method, corrosion resistance, installation and maintenance, and long-term stability. GB 3836.15-2024 sets requirements for the design, selection, installation and initial inspection of electrical installations in explosive atmospheres, which means relevant equipment cannot be evaluated by function alone; it must also fit the hazardous area on site and the engineering implementation conditions.
The fourth layer is the platform diagnosis layer, which should support tank farm grounding trends, lightning current event archives, SPD health status, static protection grounding status, alarm grading, operation interlocking, risk maps and safety reports. The fifth layer is the O&M closure layer, which needs to implement alarm confirmation, operation reminders, field review, maintenance handling, recovery confirmation, event archiving and periodic evaluation.
Fig. 5A: Field protection and status sensing layer.
5. Why must communication methods and explosion-proof selection be explained separately?
The communication method in an oil and gas storage tank farm cannot be chosen merely by asking "can it go online". RS485/Modbus suits in-cabinet or nearby acquisition; Ethernet and fiber optics suit station-level platform access and interference-resistant transmission; 4G/5G suits scattered points and retrofit projects; LoRa, NB-IoT and similar technologies suit low-power, low-frequency status data.
But in oil and petrochemical sites, what matters even more is whether the communication and power supply solutions fit explosive hazardous areas, are easy to maintain, resist interference, support broken-link data continuation and can enter the safety monitoring system stably. Explosion-proof compliance is the entry threshold; data reliability is the long-term value.
Therefore, during design, explosion-proof terminals, edge gateways, communication links, platform interfaces and maintenance should be considered together. Buying a device that can go online does not mean a reliable smart lightning protection system has been built.
6. What misconceptions should be avoided during system implementation?
The first misconception is installing only a grounding resistance monitor without connecting it to a platform. If the grounding resistance is only displayed on site without trends, alarms, records and review, its value will be very limited. The second misconception is looking only at grounding resistance and ignoring the static protection grounding status during loading/unloading operations. Tank farm safety is not just about the ground grid; electrostatic discharge during operations is equally critical.
The third misconception is looking only at the explosion-proof certificate and not at data reliability. Explosion-proof compliance is the bottom line, but long-term data stability, measurement accuracy, anti-interference capability and communication reliability are equally important. The fourth misconception is separating SPD status from grounding status, which prevents the platform from judging the complete risk chain. The fifth misconception is alarms without closure; if alarms are not confirmed, reviewed, handled and archived, the platform value drops significantly.
Real system implementation is not about installing equipment and being done, but letting data enter the platform, letting alarms be graded, letting the field be reviewed, and letting results be accumulated.
7. How does FEXLINK understand smart lightning protection systems for oil and gas storage tank farms?
FEXLINK believes that the online grounding resistance monitoring and smart lightning protection system for oil and gas storage tank farms should not be understood as a single-equipment purchase, but as a key data chain in the safety monitoring system of major hazard installations.
What the FEXLINK system focuses on is not single-point values, but whether the grounding status remains continuously stable, whether electrostatic discharge is reliable, whether lightning current events are traceable, whether SPDs are still effective, whether alarms can enter the safety monitoring platform, and whether handling forms a closed loop.
This system needs to achieve three shifts: from one-time grounding testing to grounding status trend management; from lightning protection equipment configuration to lightning protection system operation monitoring; from single-point alarms to closed-loop safety for major hazard installations.
Fig. 5B: Platform diagnosis and safety closure layer.
Conclusion: For tank farm smart lightning protection, the core is bringing grounding and lightning protection status into the safety monitoring system
The online grounding resistance monitoring and smart lightning protection system for oil and gas storage tank farms is not for displaying a few more data points, but for bringing grounding, static protection, lightning protection, surge protection and equipment alarms into a unified risk management workflow.
For major hazard installation scenarios for hazardous chemicals, the real value of the system is not "whether equipment is installed", but whether the operating status remains continuously known, whether abnormalities are alarmed in time, whether handling forms a closed loop, and whether risks can be identified and managed in advance.
References
National Standard Information Public Service Platform: GB 17681-2024, Technical Specification for Safety Monitoring of Major Hazard Installations for Hazardous Chemicals.
Ministry of Emergency Management: Publication of the Mandatory National Standard Technical Specification for Safety Monitoring of Major Hazard Installations for Hazardous Chemicals.
National Standard Information Public Service Platform: GB 3836.15-2024, Explosive Atmospheres - Part 15: Design, Selection and Installation of Electrical Installations.
