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              GDCO-301 Online Monitoring System of Circulating Current on Cable SheathCables above 35kV are mainly single-core cables with metal sheath. Since the metal sheath of the single-core cable is hinged with the magnetic field line generated by the AC current in the core wire, the two ends of the single-core cable have a high induced voltage. 
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              GDDJ-HVC Dielectric Loss Tester for Live Capacitive EquipmentThere are usually two ways to monitor the insulation condition of high voltage electrical equipment in substations: online monitoring and live (portable) online detection. 
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              GDDJ-HVC Substation Temperature Monitoring SystemThere are usually two ways to monitor the insulation condition of high voltage electrical equipment in substations: online monitoring and live (portable) online detection. 
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              GDF-5000 Online Insulation Monitoring Device for DC SystemGDF-5000/OL Online Insulation Monitoring Device for DC System is used for real-time online monitoring of insulation status of DC bus and branch. This device adopts the detection method of DC balanced resistance. 
