Glow plug, also known as glow plug. The glow plugs provide thermal energy for improved starting performance when the diesel engine cools in severe cold. At the same time, the glow plug is required to have the characteristics of rapid temperature rise and long-lasting high temperature state.
Glow plug, also known as glow plug.
The glow plugs provide thermal energy for improved starting performance when the diesel engine cools in severe cold. At the same time, the glow plug is required to have the characteristics of rapid temperature rise and long-lasting high temperature state. [1]
Characteristics of various glow plugs
Metal glow plug features
Open-speed warm-up time: 3 seconds, the temperature can reach more than 850 degrees Celsius
·After heating time: After the engine is started, the glow plugs maintain the temperature (850 degrees Celsius) for 180 seconds to reduce pollutants.
·Operating temperature: about 1000 degrees Celsius.
Ceramic glow plug features
Warm-up time: 3 seconds, the temperature can reach more than 900 degrees Celsius
·After heating time: After the engine is started, the glow plugs maintain the temperature (900 degrees Celsius) for 600 seconds to reduce pollutants.
Schematic diagram of ordinary glow plug structure
·Operating temperature: about 1150 degrees Celsius.
Fast Preheat Metal Glow Plug Features
Warm-up time: 3 seconds, the temperature can reach more than 1000 degrees Celsius
·After heating time: After the engine is started, the glow plugs maintain the temperature (1000 degrees Celsius) for 180 seconds to reduce pollutants.
·Operating temperature: about 1000 degrees Celsius
PWM signal control
Fast Preheating Ceramic Glow Plug Features
Warm-up time: 2 seconds, the temperature can reach more than 1000 degrees Celsius
·After heating time: After the engine is started, the glow plugs maintain the temperature (1000 degrees Celsius) for 600 seconds to reduce pollutants.
·Operating temperature: about 1150 degrees Celsius
PWM signal control
Diesel engine start glow plug
There are several different types of glow plugs, and currently the most widely used are the following three: conventional; Low voltage version of the preheater. A glow plug is screwed into each combustion chamber wall of the engine. The glow plug housing has a glow plug resistor coil mounted in a tube. Current passes through the resistive coil, causing the tube to heat up. The tube has a large surface area and can generate more thermal energy. The inside of the tube is filled with insulating material to prevent the resistance coil from contacting the inner wall of the tube due to vibration. Due to the different battery voltage (12V or 24V) and preheating device used, the rated voltage of various glow plugs is also different. Therefore, be sure to use the correct type of glow plugs. Using the incorrect glow plugs will cause premature combustion or insufficient heat.
In many diesel engines, temperature-controlled glow plugs are used. This kind of glow plug is equipped with a heating coil, which actually consists of three coils, a blocking coil, an equalizing coil and a rapid heating coil, and the three coils are connected in series. When current is passed through the glow plug, the temperature of the rapid heating coil located at the tip of the glow plug first rises, causing the glow plug to glow hot. Since the resistances of the equalizing coil and the blocking coil increase sharply as the temperature of the heating coil increases, the current through the heating coil decreases accordingly. This is how the glow plug controls its own temperature. Some glow plugs do not have equalizing coils installed due to their temperature rise characteristics. The temperature-controlled glow plugs used in the new super glow plugs do not require current sensors, which simplifies the preheating system. [2]
Glow plug monitor type preheater edit broadcast
The glow plug monitor type glow device consists of glow plugs, glow plug monitors, glow plug relays and other components. The glow plug monitor on the dashboard shows when the glow plugs are hot.
The glow plug monitor is installed on the instrument panel to monitor the heating process of the glow plug. The glow plug has a resistor connected to the same power source. And when the glow plug turns red, this resistor also turns red at the same time (usually, the glow plug monitor should glow red for about 15 to 20 seconds after the circuit is turned on). Several glow plug monitors are connected in parallel. Therefore, if one of the glow plugs is shorted, the glow plug monitor will turn red earlier than normal. On the other hand, if a glow plug is open, it will take longer for the glow plug monitor to glow red. Heating the glow plug for longer than the specified time will damage the glow plug monitor.
The glow plug relay prevents large amounts of current from passing through the starter switch and ensures that voltage drops due to the glow plug monitor will not affect the glow plugs. The glow plug relay actually consists of two relays: when the starter switch is in the G (preheat) position, one relay current through the glow plug monitor to the glow plug; when the switch is in the START (start) position, the other relay. A relay delivers current directly to the glow plug without going through the glow plug monitor. This prevents the glow plug from being affected by the voltage drop due to the resistance of the glow plug monitor during start-up.
