IC3600SBMB1D1C - Speedtronic Mark ll PC Board

SPECIFICATIONS

Part No: IC3600SBMB1D1C
Manufacturer: General Electric
Function: Bus Monitor Card
Series: Mark I and II
Repair: 3-7 Day
Availability: In Stock
Country of Manufacturer: United States (USA)

Functional Description

IC3600SBMB1D1C is a Bus Monitor Card developed by GE. It is a part of Mark I and II control system. Mark I and It manage all key turbine parameters such as start-up, speed, temperature, and load using electrical and electronic computation, providing high reliability and precision.

Droop and Isochronous Control Modes in Speedronic Systems

• In typical generator drive applications, turbine-generator units are operated at approximately 4% droop. This operating mode enables the generator to effectively share electrical load with other units running in parallel on the same grid. Droop control allows the frequency to decrease slightly as load increases, thereby ensuring that each unit contributes proportionally to the total system load, maintaining grid stability.
• However, the turbine control system developed by GE offers an optional and highly efficient feature: automatic and instantaneous switching to isochronous control mode for isolated or stand-alone operation. This transition occurs with minimal frequency deviation, providing a seamless shift from grid-connected to isolated operation.

Isochronous Mode

In isochronous mode, the turbine maintains a constant speed (frequency) regardless of load changes. This is particularly useful in isolated systems where frequency stability is critical. The system enables this by using a high-accuracy speed reference, allowing the turbine to operate precisely at 50 or 60 Hz, depending on system requirements, with frequency variation held to within ±0.1 Hz.

Seamless Transition Between Modes

When the unit needs to reconnect to the grid for parallel operation, it can automatically revert to droop mode. This is done without any significant load shift, ensuring stable and uninterrupted operation during the transition.

The switch to isochronous mode is achieved by:

• Eliminating the steady-state feedback and
• Removing the Full Speed No Load (FSNL) bias using Function Code 83 (83 FC)
• While retaining the transient feedback - This effectively transforms the speed control loop into an integrator, which is a key characteristic of isochronous operation. 

WOC is happy to assist you with any of your GE requirements. Please contact us by phone or email for pricing and availability on any parts and repairs.

FREQUENTLY ASKED QUESTIONS

What is IC3600SBMB1D1C?
It is a Bus Monitor Card developed by GE.

Why is droop control important for parallel operation?
Droop control ensures stable and proportional load sharing among generators. Without it, one unit could end up carrying too much load, leading to instability or equipment damage.

What is isochronous control mode?
In isochronous mode, the turbine maintains a constant speed (or frequency) regardless of load changes. This is especially useful in isolated (off-grid) systems, where frequency must remain stable even when the load fluctuates.

Will switching from isochronous back to droop mode cause a load shift?
No, the system is designed to allow seamless transfer back to droop mode without causing a noticeable load shift, ensuring smooth reintegration into the grid.