- Unmanned Pump Control, Choose 3S
Shanghai 3S Global Company Limited

A few months earlier, Zhang Jun's team had been assigned a daunting task - to develop a water pump controller capable of withstanding 2 kV lightning surge. In the first month, the prototype easily passed the 1 kV surge test, filling the team with confidence. Zhang Jun wrote in his project log: "Progress is smooth; we expect to reach the 2 kV surge resistance target next month."


Each redesign led to another surge test - and often another burnt board. Late into the night, Zhang Jun and his team ran endless tests, logging data and tracing every potential failure path. Finally, in the seventh prototype, the 2 kV surge test passed flawlessly, the core circuitry remained stable, and the software continued running. Applause broke the long silence in the lab.
Just as the team was celebrating, the company announced a new goal - to meet 4 kV surge immunity, driven by tougher market demands. The mood in the lab instantly grew tense.
"4 kV? We barely survived 2 kV - doubling that is impossible!" someone exclaimed.
Zhang Jun remained calm. "If we're going to make a breakthrough," he said, "let's make it count."
Zhang Jun led the team to rethink the design. They realized that a single protection layer could never handle the complexity of real surge events. Thus, they introduced a multi-stage protection strategy:
Stage 1: High-energy MOVs at the power input absorb the bulk of surge energy.
Stage 2: Fast-clamping devices such as TVS diodes suppress residual surge voltage peaks, protecting the power module and logic circuits.
Stage 3: Filtering, isolation, and PCB zoning prevent surge coupling into the control IC and signal layers.
They also optimized the grounding layout and discharge path, ensuring that surge energy was diverted efficiently without back-coupling into sensitive circuits.


After two months of calculation and repeated tuning, the new design was ready for testing.
At 2 kV, the waveform remained smooth. 3 kV - still stable.
At 4 kV, after the surge pulse,the controller's indicator lights stayed on and all operational data remained intact.
Cheers erupted in the lab. Zhang Jun looked at the controller running steadily and finally allowed himself a long-awaited smile.
Today, this battle-tested water pump controller has been operating reliably across harsh environments worldwide, quietly safeguarding water systems. Zhang Jun and his team have already moved on to new challenges - for them, every breakthrough is a promise kept: to remain steadfast through every storm.
This spirit also embodies one core value of our "3S" brand philosophy(Summit, Stone, SunRay):
Stone - like solid rock, our products stand firm, upholding our commitment to quality, reliability, and consistency, providing a solid foundation for our customers' success.
"Success," Zhang Jun often says, "is simply holding on a little longer than those who give up." This was the secret behind the team's ultimate success.
This is the story of a journey from 1 kV to 4 kV - a voyage of perseverance, professionalism, and passion written through countless nights of hard work.


