Automatic generator set controller PCS-994

with power controller functionprotection moduledigital

Product Overview
PCS-994 is a frequency and voltage controller designed to manage under-frequency, under-voltage, over-frequency and over-voltage conditions. It supports staged load shedding, generator shut-down and system separation to restore stability, and can initiate hydro-generator self-start in under-frequency scenarios. The device is built on an advanced multi-processor platform and supports IEC 61850-8-1 (MMS). A front RJ-45 port simplifies testing and commissioning.

Protection & Control

• Under-frequency load shedding — automatic staged load shedding based on frequency decrease to restore generation-load balance; 8 stages (5 basic + 3 special).
• Accelerated under-frequency shedding — df/dt-based acceleration allowing immediate operation of stage 2 and/or 3 after stage 1 for severe generation shortfall.
• Over-frequency protection — staged generator shut-down to restore frequency; 5 stages.
• Under-voltage load shedding — staged load shedding based on voltage decline to stabilize system voltage; 8 stages (5 basic + 3 special).
• Accelerated under-voltage shedding — dU/dt-based acceleration to prevent voltage collapse.
• Over-voltage protection — system separation to restore voltage; 3 stages.
• df/dt and dU/dt blocking — blocking functions to avoid undesired operations caused by short circuits, load feedback or VT failures.

Monitoring and Measurement

• VT circuit supervision (VTS).
• Self-diagnostics.
• Event recorder: 1024 change-of-binary-input events, 1024 supervision events, 1024 operating logs.
• Disturbance recorder: 32 disturbance records with waveforms; COMTRADE-compatible format.

Communication

• Up to 4 x 10Base-T/100Base-TX copper Ethernet ports supporting IEC 61850 (MMS), DNP3.0 or IEC 60870-5-103 over TCP/IP.
• Up to 2 x 100Base-FX optical Ethernet ports (shared with copper ports) supporting IEC 61850, DNP3.0 or IEC 60870-5-103 over TCP/IP.
• 2 x RS-485 serial ports for IEC 60870-5-103.
• 1 x RS-485 serial port for clock synchronization.

User Interface

• Front HMI with large LCD and 9-button keypad.
• 1 front RJ-45 port for testing and setting.
• 1 rear RS-232 or RS-485 port for printer.
• Language selection: English + selected language.
• Assistant software: PCS-Explorer.

Technical specifications

• Model: PCS-994.
• Brand: NR Electric Co., Ltd.
• Platform: advanced multi-processor platform.
• Supported protocols: IEC 61850-8-1 (MMS), DNP3.0, IEC 60870-5-103.
• Under-frequency load shedding: 8 stages (5 basic + 3 special); accelerated via df/dt.
• Under-voltage load shedding: 8 stages (5 basic + 3 special); accelerated via dU/dt.
• Over-frequency protection: 5 stages (generator shut-down).
• Over-voltage protection: 3 stages.
• Outputs: 30 groups; each group configurable for load shedding or generator shut-down; output matrix configurable per stage.
• Event recorder capacity: 1024 change-of-binary-input events, 1024 supervision events, 1024 operating logs.
• Disturbance recorder: 32 records with waveforms, COMTRADE compatible.
• Ethernet: up to 4 copper 10/100 ports and up to 2 100Base-FX optical ports (shared with copper ports).
• Serial ports: 2 RS-485 for IEC 60870-5-103; 1 RS-485 for clock sync; 1 RS-232/RS-485 for printer.
• Front RJ-45 for testing and setting.
• HMI: large LCD + 9-button keypad.
• Assistant software: PCS-Explorer.