Abstract:Shanghai Chemical Industry District Caojing Pump-station is responsible for the flood-preventing responsibilities in flood seasons. It’s the first pump-station to use 10 kV high voltage large-sized submersible motor-pumps in the world. Because the leisure time is long, there needs to monitor the insulating resistance of the submersible motors to assure the successful operation in flood seasons. This article introduces the function, principle, manufacture, test and result at site of the HDS-1 Large-sized Submersible Motor-pump Static Insulating Resistance Monitor in detail. The successful design, manufacture and use of the monitor, solves one of the difficult problem to develop large-sized submersible motor-pumps.