Operation manual of ky-bc SCR zero crossing trigger

　　I. overview

　　Ky-bc SCR zero crossing trigger is a SCR trigger controller of three-phase AC contactless switch. It has the function of self synchronization, which avoids the trouble of identifying synchronization and phase sequence in traditional SCR circuit, and has superior self detecting zero crossing signal, which is safe and reliable. It is suitable for all kinds of three-phase AC contactless switching circuits, especially for three-phase AC contactless switching devices of shunt compensation capacitors.

　　II. Performance characteristics

　　○ High reliable SCR voltage zero crossing trigger, three-phase independent control, pulse isolated output, safe and reliable.

　　○ It has self synchronization function, which avoids the trouble of traditional silicon controlled circuit identifying synchronization and phase sequence, and is easy to use and debug.

　　○ It is applicable to resistive load, inductive load, capacitive load and other types.

　　○ Integrated structure, simple wiring, good interchangeability.

　　○ Strong driving ability, each circuit can output 600mA current, 6V trigger voltage, and drive 4000A thyristor.

　　○ It is reliable in operation, with strong anti-interference ability, strong applicability and high pressure resistance.

　　III. main technical indicators and use

　　Control signal: A, B and C are controlled independently, DC control voltage is input DC12V (minimum current 1mA).

　　Trigger output: six channel wide pulse trigger, pulse isolated output.

　　Trigger current peak value ≥ 800mA

　　Trigger voltage peak value ≥ 6V, can trigger ≤ 4000A thyristor (thyristor).

　　Indication function: in control indication

　　Applicable voltage: three phase ac220-480v

　　Operating environment: ambient temperature - 35 - + 55 ℃

　　Relative humidity ≤ 85%

　　No conductive dust and corrosive gas

　　Overall dimension: 90 × 140 × 45mm see attached Fig. 1 for details

　　Weight: 0.25kg

　　IV. working principle

　　The output trigger pulse of the controller must have two conditions at the same time: the control input is valid and the voltage at both ends of the thyristor is zero. Without either of the two conditions, the trigger pulse cannot be output. The first effective cycle of the control signal detects zero crossing, which means the trigger pulse is output when the zero crossing condition is met, and the trigger pulse is output continuously in the effective period of the control signal in the future.

　　Terminals 1, 2 and 3 of the controller are controlled by a, B and C respectively, and terminals 4 are common terminal (GND); terminals 5 and 6 can be connected with external temperature switch, and terminals 7, 8, 9 and 10 can be standby (the combination can be connected with radiator fan control).

　　Terminal 11-22 is the output terminal of trigger pulse, terminal marked G is "+"; terminal marked K is "-".

　　There are control indicators on the panel of the controller. The indicator light is on when the control signal is input.

　　V. usage

　　1. Wiring: refer to the wiring list and Figure 2 for wiring.

　　External high-level signal control is adopted, 1 #, 2 #, 3 # respectively correspond to 4 # (GND) common terminals, respectively add 12V DC voltage, 11 # - 22 # terminals are respectively connected to G and K poles of thyristor, note: G and K of controller a + correspond to main circuits GA +, Ka +, and so on, and cannot be connected wrongly.

　　In order to prevent interference, it is better to route the given control line and AC power line separately and keep them as short as possible. If it is inconvenient to separate the wires, the given control wire shall use stranded shield wire.

　　2. Test and commissioning.

　　Check the wiring before power on, and check the insulation between the power lines and other control lines with a multimeter to ensure everything is correct.

　　Disconnect the main load, connect a resistance test load for testing, especially when the load is a capacitor or motor and other circuits, disconnect the actual load during the test. The incandescent lamp or electric furnace shall be connected to the connection type corresponding to the working voltage for the test load, and the actual load shall be recovered after the test is correct.

　　Vi. troubleshooting of abnormal state

　　1. SCR has no output, no current or voltage:

　　The in indicator light on the panel is not on and SCR cannot work. Please check whether the control signal of the trigger is connected correctly.

　　Check the temperature switch to confirm whether the SCR is over temperature.

　　Check whether SCR trigger wire is connected correctly or damaged.

　　2. If the trigger has problems that cannot be solved by users, please do not hesitate to contact us, and we will solve them for you in time.