GE gas turbine and steam turbine and Bently Nevada Machinery protection systems belong to TSI which is the “first line of defense” for ensuring the safe operation of the equipment

However, there are significant differences in the key areas of monitoring and protection among them, which stems from their distinct working principles and operating environments.

Core Difference: Gas Turbine vs. Steam Turbine

Monitoring program	Gas Turbine	Steam Turbine
critical component	Compressor, combustion chamber, turbine (turbo)	High-pressure cylinder, medium-pressure cylinder, low-pressure cylinder
Speed monitoring	Very high rotational speed. Must pass through the critical speed quickly.	The rotational speed is relatively low, but it is also strictly monitored.
vibration monitoring	High and low pressure rotor vibration (shaft vibration/wheel vibration)	Vibration monitoring for multi-rotor and multi-bearing systems
Flame/Temperature Monitoring	Core protection: Flame detector, exhaust temperature thermocouple	uninvolved
axial displacement	Monitoring the wear of thrust bearings	Extremely crucial: High thrust, strict monitoring
differential expansion	Monitor the gap between the moving and stationary parts	Extremely crucial: The thermal expansion difference between the cylinder and the rotor
decentration	Monitor rotor bending	Extremely crucial: Monitoring rotor thermal bending during the start-stop process
The casing expands	Monitor the deformation of the casing	Monitoring the thermal expansion of the cylinder
Valve movement	uninvolved	Extremely crucial: Test of the main steam valve and regulating valve movements
lubricating oil system	Monitor oil pressure, oil temperature, oil level and metal particles	Extremely crucial: Test of the main steam valve and regulating valve movements Monitoring of oil pressure, oil temperature and oil level is extremely demanding

The core function of the monitoring and protection system

Whether for gas turbines or steam turbines, the monitoring and protection system plays an irreplaceable role.

1. Real-time monitoring: Continuously collect key parameters such as turbine speed, shaft vibration, bearing vibration, axial displacement, expansion difference, cylinder expansion, eccentricity, temperature, pressure, flame, etc.

2. Logical protection: When the monitored values reach the set alarm or shutdown thresholds, the system will trigger an alarm signal or directly issue a shutdown command (such as closing the fuel valve, main steam valve).

3. Fault diagnosis: By analyzing data such as vibration spectra and trends, determine the type of fault (such as imbalance, misalignment, oil film oscillation), providing a basis for predictive maintenance.

4. Historical records: Record waveform data before and after the incident, facilitating post-event analysis of the root cause.

The manifestation in GE products

Core safety of Mark V / Mark VIe: The internal TMR (Triple Redundancy) or SIL (Safety Integrity Level) architecture of the system is specifically designed to implement critical protection logic. For instance, when the vibration value exceeds the shutdown threshold, the controller will directly cut off the fuel/steam through hard-wired output, without going through the upper computer, ensuring high reliability.

Specialized cards: The system contains a large number of I/O cards for monitoring and protection. For example, the DS200SHVMG1AFE (High Precision Analog Input Module) in Mark V can be used to collect signals from vibration sensors; the IS220PSFDH1A (Flame Detector Power Supply) in Mark VIe is used for gas turbine flame monitoring.

Therefore, if you are maintaining the gas turbines or steam turbines of GE, the Mark series control system itself already incorporates these monitoring and protection functions. If you need an independent, more precise vibration monitoring system, you would typically choose a professional brand like Bently Nevada (now part of Baker Hughes) and then connect the signals to GE’s control system for protection and display purposes.

Bently Nevada, professional products offer professional protection, with a wide range of products, excellent quality and reasonable prices.

3500 Surveillance protection system, Proximitor eddy current sensor probe

3500/15  106M1079-01

3500/22M 138607-01 288055-01

3500/42M 176449-02

3500/50   286566-02

3500/61  163179-02

3500/92  136180-01

330180-50-00  330103-00-04-10-02-00   330190-040-01-00

EX2100, EX2000 Excitation system card IS200 series DS200 series

IS220PDOAH1A  IS220PAICH2A  IS220UCSAH1A  IS220PDIOH1B IS220YDOAS1A  IS200BAIAH1BEE  IS200CABPG1BAA IS200DSPXH1BBD IS420ESWBH3A IS420UCSBH4A IS420UCSBH1A IS420UCSBH1A IS215VCMIH2B IS215ACLEH1CA IS215VPROH1BD