A generator control system for two generators with remote control and automatic transfer capability.
The system is primarily operated from system control panels which may be located anywhere on the vessel. One of these control panels is designated as the engineers control panel and will have supervisory control of the remote control and automatic transfer functions. Each system control panel will have a dimmer to allow reduced lighting at night and a lamp test switch to verify the status of all lamps on the panel. The system of control panels are capable of being mounted flush or on a standard NEMA 4 enclosure.
The system does provide continuous indication of the running status of each generator, and of the open/closed status of each main circuit breaker at each system control panel.
The system continuously monitors the lubricating oil pressure and cooling water temperature of each generator engine and the output voltage and frequency of each generator. If any of these monitored conditions fall outside preset limits for a preset time, an alarm will sound and a description of the fault condition is displayed at each system control panel. Audible and visible alarms will also be activated in the engine room. Acknowledging a fault at any system control panel will silence the alarm, but the display of the fault condition will remain available until the fault has cleared. A subsequent occurrence of the fault will produce a new alarm.
The system provides a remote start and stop capability for both generator engines and remote close and open capability for both main circuit breakers at any system control panel. The availability of this remote capability is under the control of the vessel engineer by means of an enabling switch on the engineers control panel and is indicated by a light on each system control panel. It is not possible by means of the remote controls to engage a starter on an operating generator, to close a main circuit breaker if the other main circuit breaker is closed, or to close a main circuit breaker if the corresponding generator is not running or is in fault.
The system, when a fault occurs on the operating generator or engine, automatically starts the other generator engine. When the new generator is operating without fault, the system automatically opens the faulted generator's main circuit breaker and then closes the new generator's main circuit breaker to put the new generator on line in place of the faulted generator. The maximum time required for the automatic transfer of generators, from the detection of a fault on one generator to closing of the other main circuit breaker, is less than seven seconds plus the starting time of the new generator. The availability of this automatic transfer capability is under the control of the vessel engineer by means of an enabling switch on the engineers system control panel and is indicated by a light on each other system control panel. It is not possible by means of the automatic transfer function to engage a starter on an operating generator, to close a main circuit breaker if the other main circuit breaker is closed, or to close a main circuit breaker if the corresponding generator is not running or is in fault. The automatic transfer function will not open the circuit breaker for the faulted generator until the new generator is running without fault.
The system includes a lighted pushbutton at the main switchboard to allow local electrical control of the main circuit breakers when neither the remote control or automatic transfer functions have been enabled, or when the system has been turned off or has failed. The lights on these pushbuttons will light when and only when they are functional. It is not possible, by means of these pushbuttons, to close one circuit breaker if the other is already closed.
The system is powered by an interruptible power source which is in turn powered from the output of whichever generator is active. Main circuit breaker motor operators are powered from the output of whichever generator is active. No other external power is required.
All circuits are fail-safe designed to prevent equipment damage or unexpected loss of vessel electrical power. The system opens the circuit for each generator engine starter solenoid while the generator is running.
The system monitors the performance of its own electronic circuits and provides an alarm and fault message in case of failure.
The system has the optional capability of logging all alarms, acknowledgments, alarm clearings, remote operations, and transfers on a data printer.
The system can have the optional capability of monitoring up to 100 additional switch type inputs and of being upgraded to accept analog sensor inputs and displaying the resulting information on CRT monitors with bar graph and digital displays.
The system is ABS and USCG approved.