300 kVA DVR for Semiconductor Packaging and Testing — SJSEMI
SJSEMI, a semiconductor packaging and testing company, installed a 300 kVA Winzpower Dynamic Voltage Restorer to protect sensitive wafer packaging and testing process equipment. The project uses a 3-phase 400 V DVR configured for a maximum voltage sag depth of 60%, equivalent to 40% residual voltage, with a required support duration of 3 seconds.
The Dynamic Voltage Restorer (DVR) is installed on the dedicated low-voltage feeder supplying the protected equipment. The protection boundary is therefore centered on the sensitive process load rather than the total factory load.
Project Background
SJSEMI operates in semiconductor packaging and testing, where electrically sensitive process and test equipment depends on a stable supply. A short voltage sag can disturb equipment controls or interrupt an active process even when the wider utility supply has not experienced a sustained outage.
The project objective was to add a dedicated voltage-sag protection layer for the selected wafer packaging and testing equipment. Detailed downstream equipment identities and process information are not included in the project record because semiconductor production areas apply strict confidentiality and photography controls.
This case therefore focuses on the information that can be documented: the electrical system, DVR rating, voltage-sag requirement, support duration, installation position, protected-load boundary, and actual installed DVR enclosure.
Voltage Sag Protection Requirement
The specified sag depth and residual voltage describe the same design condition from opposite directions: residual voltage equals 100% minus sag depth. For this project, a 60% voltage sag corresponds to 40% residual voltage.
| Item | Project Requirement |
|---|---|
| Customer | SJSEMI |
| Industry | Semiconductor packaging and testing |
| System Voltage | 400 V |
| Phase | 3-phase |
| DVR Capacity | 300 kVA |
| Maximum Sag Depth | 60% |
| Minimum Residual Voltage | 40% |
| Required Support Duration | 3 s |
| Protected Load | Sensitive wafer packaging and testing process equipment |
DVR Configuration
The installed solution is a 300 kVA, 3-phase, 400 V DVR configured around the specified protected load and disturbance requirement. Its project duty is defined by the combination of the protected-load rating, 60% maximum sag depth, 40% minimum residual voltage, and 3-second support duration.
These parameters must be considered together. The kVA rating defines the power level of the protected feeder, while the sag depth and support duration define how much voltage support is required and for how long. The project information supplied for this case does not include cabinet dimensions, transformer impedance, short-circuit level, or internal downstream equipment data, so no assumptions are made about those items.
Electrical Connection and Protection Boundary
The documented connection sequence is:
Transformer → Main LV Distribution Cabinet → Sensitive Equipment Feeder → DVR → Protected Sensitive Equipment
The DVR is installed after the main low-voltage distribution cabinet on the dedicated feeder supplying the sensitive equipment. It is not presented as protection for the entire plant bus. This feeder-level arrangement defines a clear boundary around the process equipment that requires voltage-sag support while other general plant loads remain outside the DVR protection scope.
On-Site Installation
The project photograph shows the real installed DVR enclosure in the designated electrical installation area. It documents the delivered cabinet arrangement without revealing the customer’s downstream production equipment or internal process layout.
Engineering Outcome
The installed DVR system is configured to support the protected load through the specified 60% sag depth and 3-second support-duration requirement. Electrically, the project establishes a dedicated protection layer between the low-voltage distribution system and the selected sensitive process equipment.
The available project record confirms the installation, system voltage, DVR capacity, target sag depth, residual-voltage level, support duration, and feeder-level topology. It does not include a recorded post-installation sag waveform, production-loss statistics, or downtime-reduction data. Accordingly, this case does not claim a measured event outcome beyond the documented engineering configuration.
Project Summary
The SJSEMI project combines a 300 kVA DVR with a clearly defined sensitive-load feeder on a 3-phase 400 V system. The unit is configured for 60% sag depth, 40% residual voltage, and 3 seconds of support. The connection strategy protects the selected semiconductor packaging and testing equipment without treating the complete facility load as the DVR sizing basis.
For the information normally required to prepare a comparable project specification, see the DVR Selection & RFQ Guide.
Detailed process-equipment information is intentionally omitted to protect customer confidentiality and semiconductor production security.
Related Product
Dynamic Voltage Restorer (DVR): Winzpower DVR systems provide voltage-sag compensation on the low-voltage side of a protected feeder or process transformer, so the protected load is supported through the specified sag depth and support duration.
