Model Interpretation

8237: ProTech-GII standard three-channel overspeed controller base series code;

1600: Fixed factory configuration variant, three independent display operation channels, dual power input(AC+DC), built-in speed simulation test source, standard Modbus-RTU communication, front panel integrated local parameter setting and speed real-time display.

Technical Specifications

Electrical & Mechanical Parameter

Power Supply: Dual redundant input, 24VDC(18~32VDC) + 85~264VAC universal alternating current, dual-circuit independent power design

Working Ambient Temp: -20℃～+60℃, Storage: -40℃～+85℃, Humidity 5%~95%RH non-condensing

Overall Size: 330×445×159mm, panel embedded mounting, net weight≈6kg, front casing IP54 protection grade

Speed Input: Magnetic pickup(MPU) frequency signal input, measurable rotating speed range 0~99999RPM; 4–20mA analog speed retransmission output per channel

Safety Standard: SIL2 safety level approval, Class I Div.2 hazardous area certification, three independent trip relay outputs for emergency shutoff valve drive

Internal Hardware Structure

Three fully isolated independent control channels, every channel equipped with independent CPU, signal acquisition circuit, display and operation keypad; internal embedded calibration frequency generator for offline overspeed threshold simulation test without external signal source.

Interface and Communication Configuration

Front Interface: Three independent LCD digital speed display + 15-key parameter setting keypad per channel for trip threshold, acceleration protection value onsite calibration

Rear Terminal: MPU speed input terminals, dual power wiring terminals, trip relay dry contact output terminals, isolated RS485 Modbus-RTU communication port for DCS upper computer speed data uploading and remote monitoring.

Core Function

Triple redundant overspeed monitoring: Three channels independently sample rotor speed, 2-out-of-3 voting logic outputs trip signal to cut off turbine fuel/steam inlet when overspeed exceeds preset value, single channel fault does not trigger false shutdown.

Acceleration overrun protection: Built-in rapid acceleration detection logic, execute emergency trip when unit abnormal sharp speed rising occurs during startup or abnormal load dump.

Local parameter calibration: Front panel keypad modifies overspeed setpoint, acceleration protection threshold, no extra configuration software required for field commissioning.

Analog speed transmission: Per-channel 4–20mA output corresponding to actual rotating speed, real-time transmit speed value to central control room DCS system.

Self-diagnosis & fault record: Real-time self-check for channel failure, wiring break, MPU fault; store historical trip fault code for troubleshooting inquiry.

Applicable Scenarios

Large industrial steam turbine generator set, heavy-duty gas turbine unit, hydroelectric turbine, petrochemical compressor driving prime mover, offshore platform genset; installed on local turbine protection cabinet as independent safety protection device matching digital governor system.

Operation and Maintenance Instructions

Install far from high-frequency inverter and strong electromagnetic interference equipment to prevent MPU speed signal distortion leading to misoperation.

Regular check rear dual power terminal and MPU wiring tightness, avoid loose contact causing speed sampling abnormity.

Periodically execute internal simulation overspeed test via front panel function key to verify trip relay action reliability.

Replace with original 8237-1600 spare part only; recalibrate overspeed protection setpoint after replacement before unit startup test.