Specifications:  Trigger voltage: low level is 0-2.5V, high level defaults to 3.5-5V.  Supply voltage: 5V.  Quiescent current: 12mA.  Working current: 190mA.  Load: 250V 10A (AC) or 30V 10A (DC).     Applications:  This module is widely used in the design and development of home and industrial electronic products for the majority of electronic enthusiasts. It can be used as a signal input source for single-chip computers. It is especially suitable for the electronic circuit design of students in colleges and universities. It can be docked with a single chip, or Add a level 1 drive relay or a small DC motor. The module board is divided into four types: self-locking, interlocking, triggering (jog), high level, low level, machine equipment, automation equipment modification, PLC industrial control, robot and other intelligent products.     Way of Working:  - Self-locking is pressed, the relay is pulled in, press again, and the relay is turned off. The self-locking type 2 channels are independent of each other, and can also be externally contacted and sent (CH terminal wiring), triggered by high level or low level (optional), and can be remotely controlled at the same time, such as the control of the lamps.  - Trigger (jog) is the relay pull-in when pressed, and the release button relay is turned off. It is also possible to use an external contact switch (CH terminal wiring) to trigger with a high level or low level (optional). Applicable to circuits such as electric gates, electric door locks, docking with single-chip microcomputers, etc., which only require a high or low level pulse circuit.  - Interlock is a typical application fan design, when S1 presses the S1 relay to pull in; when S2 presses S1 to open, S2's relay pulls in. The 2-way interlock can only be turned on one way, or the external contact switch (CH terminal wiring) can be triggered with high level or low level (optional). Practical applications such as electric fan gear switch circuit.     Features:  1. Adopt double-panel design PCB, 2-way independent design, without mutual interference;  2. Adopting single-chip design, the performance is stable and reliable, the anti-interference is strong, it will not be triggered by mistake, and the performance is superior;  3. The interface design is user-friendly, equipped with terminal blocks, which can be directly connected to the leads;  4. The trigger end has optocoupler isolation, and the trigger power supply can be connected to the external power supply completely, so that it is completely isolated.  5. With 2 tact switches as product testing, directly verify the stability of the product;  6. With power indicator (green LED) and 2 switch indicators (red LED);  7. Use Song Le genuine relay to control the load, the load can be withstand at 250V 10A (AC) and 30V 10A (DC);  8. Module size: 63.5x38.5x18.5mm, weight: 40g;  9. Designed with 4 bolt holes: pitch 58x33, aperture 3mm.   10. There is a signal light on each road to clearly know which switch is working.     Module interface:  power input:  DC+: The module is powered positive, and should be the same as the relay voltage;  DC-: module power supply negative;     Trigger:  1.CH1-CH2: Corresponding to 1-2 relay trigger control terminals, supporting high or low level trigger triggering;  2.