LG·FK Series Combination switching Device
Product model
| Model | Signal type | Capacitance type | Rated current | Maximum drive capacity | Rated voltage |
| LGFK-Y250V-45A | Negative DC12V | Split capacitor | 45A | 3x 10KVar | 220V |
| LGKFK-Y250V-60A | Negative DC12V | Split capacitor | 60A | 3x 13.3KVar | 220V |
| LGKFK-A-400V-45A | Negative DC12V | Split capacitor | 45A | 30kVar | 380V |
| LGKFK-A-400V-60A | Negative DC12V | Split capacitor | 60A | 40KVar | 380V |
Technical parameter
| Rated operating voltage | 380V,220V/AC+20% | ||
| Power Supply | 380V | ||
| Life time | Thousand times | ||
| Contact voltage drop | ≤100mV | ||
| Response time | ≤1000ms | ||
| Start Voltage | DC 8-18V | ||
| On and oft each time interval | ≥1 second | ||
| Control capacity | Total supplement ≤40KVar The meeting is ≤ 3 x 12KVar | ||
| Two consecutive mid interval | ≥100 seconds (Note: There must be a 100-second delay before the switch is turned on again after being turned off or turned off (preset)). | ||
| Insulation class | ≥10MQ under normal atmospheric conditions | ||
Note: "LG FK series intelligent composite switches can set the communication address via DIP switches, with an address range of 0~31."
Wiring diagram
Note: A and B are communication signal terminals, which are connected to the A and B communication signal terminals of the reactive power compensation controller or power distribution monitoring terminal using twisted-pair cables.
LG.ZFK series intelligent combination switching - Fault Alarm
The reactive power compensation controller or power distribution monitoring and metering terminal paired with the LG·ZFK series intelligent interconnected composite switch will detect fault information in the switch in real time. Furthermore, users can communicate with the controller or terminal via a host computer to obtain real-time switch operating status. In case of a fault, timely handling is possible. The table below lists the alarm faults that can be obtained from the switch information.
| 2-Phase loss | 3 - power voltage is lower than 9V |
| 4 - No sync signal found from A phase during closing operation | 5 - No sync signal found from B phase during closing operation |
| 6 - No sync signal found from C phase during closing operation | 7 - Latching relay of A phase has closed during closing operation |
| 8 - Latching relay of B phase has closed during closing operation | 9 - Latching relay of C phase has closed during closing operation |
| 10- Trigger of A phase SCS failed | 11 - Trigger of B phase SCS failed |
| 12- Trigger of C phase SCS failed | 13 - Sync signal of A phase found before the opening |
| 14 - Sync signal of B phase found before the opening | 15 - Sync signal of C phase found before the opening |
| 16 - No sync signal found from A phase after closing operation | 17 - No sync signal found from B phase after closing operation |
| 18 - No sync signal found from C phase after closing operation |
Features
1.Zero-crossing switching: The basic working principle of a composite switch is to connect a thyristor switch and a magnetically latched circuit breaker in parallel, achieving zero-crossing voltage conduction and zero-crossing current disconnection. This allows the composite switch to have the advantage of no inrush current of a thyristor switch during connection and disconnection, while having the advantage of no power consumption of a physical switch during normal operation. The implementation method is as follows: during connection, the thyristor is controlled to conduct first at the moment of zero-crossing voltage, and then the magnetically latched circuit breaker is activated after stabilization; during disconnection, the magnetically latched circuit breaker is opened first, and the thyristor disconnects after a delay at zero-crossing, thus achieving zero-crossing current disconnection.
2.The system employs a microcontroller to control the switching and intelligently monitor the operation of the thyristors, magnetically latched circuit breakers, input power supply, and load, thus providing comprehensive protection functions. These include: Voltage fault phase loss protection: the switch will refuse to close when a phase of the system voltage is lost; Power supply phase loss protection: the switch will refuse to close when a phase of the working power supply is lost; Self-diagnostic fault protection: the system automatically monitors the operating status of the thyristors and magnetically latched circuit breakers, and if a fault occurs, it will refuse to close or automatically deactivate; Power outage protection: in the event of a sudden power outage after connection, the system will automatically trip.
3.No harmonic injection: Since the conduction moment is triggered by the zero crossing of the thyristor, and the magnetic latching circuit breaker is activated after a delay, no harmonics are generated when the circuit breaker is working.
4.Low power consumption: Due to the use of magnetically protected circuit breakers, the control device only consumes power during switching operations and does not consume power under normal conditions. Furthermore, because the contact resistance of the magnetically protected circuit breaker is low, it does not generate heat, eliminating the need for external heat sinks or fans and reducing costs. This completely avoids the risk of thyristor burnout and also prevents damage to other electrical components operating in the same machine, truly achieving the goal of energy saving and consumption reduction.
5.The input signal is opto-isolated from the composite switch: it has strong anti-interference ability and is safe and reliable in operation.
Installation dimensions
