The ignition switch directly controls the circuit of the starter: the ignition switch directly controls the suction and holding coil of the starter in the starting gear, and is mostly used in the car circuit of the starter below 1.2KW; the current of the magnetic switch coil of the starter above 1.5KW is above 40A , using the start relay contacts as switches.
Starter control circuit with start-up protection: When the start-up ignition switch is at gear 0, the circuit is disconnected. When the ignition switch is in gear 1 (not started), the power supply line is routed: generator excitation, ignition coil, instrument, and indicator light. When the ignition switch is in the 2nd gear, in addition to connecting the above circuits, the starter relay circuit must also be connected: battery positive pole – ammeter – ignition switch – starter relay coil – relay normally closed contact – grounding – Battery negative pole – the starter drives the main engine. At the same time, the contact bridge connects the bypass contact of the ignition coil, the current passes through the primary of the ignition coil, and the additional resistance is isolated.
After the engine is ignited, the ground voltage of the neutral point N of the generator (about 0.5 of the regulated voltage of the generator) will cause the normally closed contact of the start protection relay in the start relay to be disconnected, cut off the grounding point of the charging indicator light, and the charging indicator The light goes out, indicating that the generator is working normally. At the same time, the grounding circuit of the starting relay coil is also cut off. When the generator is working normally, even if the ignition switch is turned to the second gear by mistake, the starter will not mesh with the flywheel, so as to avoid damaging the flywheel ring gear and the starter, and play a role The role of protecting the starter.