4 Hour Lockout Avoidance
GE’s upgrade solution mitigates the 4-hour lockout period required on LM2500 and LM6000 packages after a hot shutdown when the unit is not restarted during the defined period within the control system. For non-critical trips, modifications to the hydraulic system and controls allow for a safe restart without requiring an operator to enter the package to check the condition of the rotor.
Applicable Turbine Models
- Helps reduce or eliminate the four-hour lockout period that can occur after an emergency shutdown.
- Locked rotor check can be performed safely without entering the turbine enclosure.
- Increase Uptime
How it works
- Modification of the hydraulic starter system, including the following:
- Hydraulic rectifier manifold block
- Pressure indicator
- New start control logic block with speed feedback signals
- Hydraulic line adapters, hoses, and additional hardware
- Incorporate new control logic into the control system
- Slow Roll Mode - Allows the hydraulic start system to re-engage the starter under certain emergency shutdown conditions to slowly roll the high pressure (HP) rotor at 80–120 rpm until the customer has had an opportunity to address the trip condition and is ready to go back up to full power.
- Soft Start Mode - Under certain emergency shutdown conditions it is not advisable to attempt the Slow Roll Mode. If the customer is unable to address the cause of the shutdown within six minutes, the turbine goes into a 4-hour lockout. This upgrade allows the customer to perform an automated check to confirm if the HP rotor is locked. If the HP rotor is still locked another Soft Start can be attempted every 15 minutes.