FR Ground-Resistance Detector
FR Series
Three-pole ground-resistance online monitoring, 0.1-200 Ohm range, real-time sensing of grounding-system status, ensuring effective lightning protection.
Product Overview
The FR three-point method ground resistance monitoring module monitors ground resistance, bond resistance and other data, accurately recording ground resistance values with a monitoring accuracy of up to 0.001Ω. It uses the precision three-wire measurement method and automatically takes multiple measurements to average, ensuring accurate and reliable results. The housing is made of aluminum alloy (corrosion-resistant design, impervious to wind, rain and lightning), with a protection rating up to IP65 and an operating temperature of -20℃~60℃, suitable for long-term operation in harsh outdoor environments. It supports outdoor installation, clamp mounting, buried installation and wall-mounted installation, and can be used independently or in a network.
Core capabilities
Monitors ground resistance and bond resistance with accuracy up to 0.001Ω. Aluminum alloy corrosion-resistant housing with IP65 protection, impervious to wind, rain and lightning. On-site alarms and networked remote alarms, with real-time notification of abnormal status. RS485/Zigbee/Ethernet/4G multiple communication methods to connect to the cloud service system. Product Features
Data Generated
Product Features
Complete monitoring, high accuracy
Monitors ground resistance, bond resistance and other data, accurately recording ground resistance values with a monitoring accuracy of up to 0.001Ω.
Strong weather resistance
Aluminum alloy material (corrosion-resistant design, impervious to wind, rain and lightning) with a protection rating up to IP65, suitable for long-term operation in harsh outdoor environments.
Smart alarm push
Features on-site alarms and networked remote alarms, supports historical data queries, and notifies O&M personnel of abnormal status in real time.
Multiple communication options
Can connect to the gateway via RS485/Zigbee/Ethernet/4G etc., transmitting all kinds of data to the cloud service system.
Wide temperature range, strong weather resistance
Operating temperature of -20℃~60℃, aluminum alloy corrosion-resistant housing impervious to wind, rain and lightning, suitable for long-term operation in harsh outdoor environments.
Quick-swap modular design
Modular structure allows quick on-site replacement during maintenance, reducing downtime and improving maintenance efficiency. Selection Guide
System Topology
Selection Guide
Model naming convention
FR - 0 1 0 1 1 - R FR Product: Three-point method ground resistance monitoring module 0 Display: 0=none; 1=yes 1 Signal acquisition: 1=grid resistance; 2=grid resistance + ground voltage 0 Explosion-proof: 0=none; 1=yes 1 Mounting method: 1=outdoor; 2=indoor DIN rail; 3=indoor screw 1 Power supply: 1=DC12V; 2=AC220V; 3=solar; 4=lithium battery R Communication: R=RS485; E=Ethernet; Z=Zigbee; G=4G Model Installation position Measurement method Explosion-proof Acquisition point RS485 ZIGBEE Ethernet 4G FR-01011-R Outdoor Three-point method None Grid resistance √ --- --- --- FR-01011-Z Outdoor Three-point method None Grid resistance --- √ --- --- FR-01011-E Outdoor Three-point method None Grid resistance --- --- √ --- FR-01011-G Outdoor Three-point method None Grid resistance --- --- --- √ FR-02011-R Outdoor Three-point method None Resistance + ground voltage √ --- --- --- FR-02011-Z Outdoor Three-point method None Resistance + ground voltage --- √ --- --- FR-02011-E Outdoor Three-point method None Resistance + ground voltage --- --- √ --- FR-02011-G Outdoor Three-point method None Resistance + ground voltage --- --- --- √ Technical Parameters
| Model | Installation position / Measurement method / Explosion-proof / Acquisition point / RS485 / ZIGBEE / Ethernet / 4G |
| FR-01011-R | Outdoor / Three-point method / None / Grid resistance / √ / --- / --- / --- |
| FR-01011-Z | Outdoor / Three-point method / None / Grid resistance / --- / √ / --- / --- |
| FR-01011-E | Outdoor / Three-point method / None / Grid resistance / --- / --- / √ / --- |
| FR-01011-G | Outdoor / Three-point method / None / Grid resistance / --- / --- / --- / √ |
| FR-02011-R | Outdoor / Three-point method / None / Resistance + ground voltage / √ / --- / --- / --- |
| FR-02011-Z | Outdoor / Three-point method / None / Resistance + ground voltage / --- / √ / --- / --- |
| FR-02011-E | Outdoor / Three-point method / None / Resistance + ground voltage / --- / --- / √ / --- |
| FR-02011-G | Outdoor / Three-point method / None / Resistance + ground voltage / --- / --- / --- / √ |
Technical Parameters
Basic parameters
Operating voltage DC 12V (default) / DC 24V/AC 220V (optional) Power consumption ≤2W Operating temperature -20℃~60℃ Operating humidity <95% Weight 7kg Dimensions 260*260*107mm Housing material Aluminum alloy Protection rating IP65 Mounting method Side mounting with M7 screws
| Operating voltage | DC 12V (default) / DC 24V/AC 220V (optional) |
| Power consumption | ≤2W |
| Operating temperature | -20℃~60℃ |
| Operating humidity | <95% |
| Weight | 7kg |
| Dimensions | 260*260*107mm |
| Housing material | Aluminum alloy |
| Protection rating | IP65 |
| Mounting method | Side mounting with M7 screws |
Smart monitoring functions
Communication RS485/Zigbee/Ethernet/4G Communication protocol Modbus/MQTT protocol Ground resistance 0.01Ω~2000Ω, resolution 0.01Ω Measurement method Precision three-wire measurement Measurement time 1 minute per measurement Ground resistance accuracy ±2%rdg±3dgt Ground voltage 0.1V~600V, resolution 0.1V Voltage accuracy ±2%rdg±5dgt Installation Instructions
| Communication | RS485/Zigbee/Ethernet/4G |
| Communication protocol | Modbus/MQTT protocol |
| Ground resistance | 0.01Ω~2000Ω, resolution 0.01Ω |
| Measurement method | Precision three-wire measurement |
| Measurement time | 1 minute per measurement |
| Ground resistance accuracy | ±2%rdg±3dgt |
| Ground voltage | 0.1V~600V, resolution 0.1V |
| Voltage accuracy | ±2%rdg±5dgt |
Installation Instructions
a
Installation dimension drawing
260mm length 260mm width 107mm height M7 screw mounting b
Interface description
Interface definition No. Definition 1 Port 1: ground grid monitoring (E) 2 Port 2: auxiliary ground electrode 1 (P) 3 Port 3: auxiliary ground electrode 2 (C) 4 Port 4: communication port; Ethernet cable port for Ethernet communication; antenna port for wireless communication; no wiring for RS485 communication 5 Side port: DC12V power port for wireless or Ethernet communication, brown/blue two-core cable, brown-12V, blue-0V 6 Side port: for RS485, red-12V, black-0V, green-RS485_A, yellow-green-RS485_B
| No. | Definition |
| 1 | Port 1: ground grid monitoring (E) |
| 2 | Port 2: auxiliary ground electrode 1 (P) |
| 3 | Port 3: auxiliary ground electrode 2 (C) |
| 4 | Port 4: communication port; Ethernet cable port for Ethernet communication; antenna port for wireless communication; no wiring for RS485 communication |
| 5 | Side port: DC12V power port for wireless or Ethernet communication, brown/blue two-core cable, brown-12V, blue-0V |
| 6 | Side port: for RS485, red-12V, black-0V, green-RS485_A, yellow-green-RS485_B |
Key Points
Definition: The FR three-point method ground resistance monitoring module is a FEXLINK device for online monitoring of outdoor grounding grid resistance, based on the three-pole measurement principle. Core capabilities: long-term online monitoring of ground resistance with strong anti-interference capability, suitable for harsh outdoor environments, uploading data via RS485. Applicable scenarios: monitoring of outdoor grounding systems such as oil storage tank areas, substations, communication base stations, and lightning rod grounding grids. Related products: ESX intelligent edge computing gateway, indoor ground resistance monitor, FEXLINK Cloud ground monitoring solution.
FAQ
Related Products
FS Lightning-Protection Monitor
SPD online monitoring, microamp-accuracy leakage-current detection, supporting four/five-element and nine-element monitoring, full visibility of SPD status and life trend.
FSS Smart Surge Protective Device
Integrated smart SPD with built-in monitoring and communication, LCD/OLED display, combined lightning protection and status monitoring.
FL Lightning-Current Monitor
Peak lightning current 0.1-200kA measurement, GPS/BeiDou timing, IP67 outdoor protection, precise lightning-event attribution.
Learn MoreFR Ground-Resistance Detector Application Scenarios
Contact us for detailed solutions, quotes and technical support.