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After rectifying the 220 V AC diode, add a 400 V 10 V f capacitor, and connect 8 1K resistors to 38 LED lamps. How many large resistors should be connected to? I'm a layman, and I made a LED lamp. As mentioned above, there are 8 1K resistors. The resistor is very hot. Is it right for me to connect it? How should I connect it?
You do this with low power efficiency, no energy saving, contrary to the purpose of using LED
My practical application: connect 220 V AC, use 4 1N4004 as bridge rectifier, add 10 ohm 1 watt resistor in front of the bridge to limit current, use 200uf / 340v flash capacitor to filter behind the bridge, can get about 310 V DC; use 85 high brightness white light-emitting diodes in series and then connect 2K / 1 watt current limiting resistor, practical two groups in parallel, work normally. The actual voltage of light-emitting diodes is about 275 V, 20 mA current, high efficiency
If there are few series LEDs, most of the power is wasted on the series resistor, and the efficiency is reduced
Calculation method: resistance = (310-85 * 3.3) / 20mA = 1.75k (actual 2K / 1W, working current 17.5ma, less than rated working current, relatively safe)
High brightness white light tube parameters: rated working voltage 3.3V, current 20mA, life more than 50000 hours
In switching power supply, a rectifier diode is connected in series with (a high frequency filter capacitor and a resistor in parallel). What is the use of this resistor
Switching power supply needs a minimum output current, which should be maintained when there is no external load
Why should the rectifier Schottky diode at the output end of the switching power supply of the charger be connected in parallel with a chip capacitor and a 10 Ohm Chip resistor, which are connected in series,
A peak absorption circuit is formed. When the half cycle peak of the transformer comes, the peak value will be charged to the capacitor after current limiting through the resistor. When the cycle peak is converted to the second half cycle, the capacitor will discharge through the current limiting resistor to absorb the peak voltage and protect the diode
When the following appliances are connected to the home circuit and work normally, the household appliances with power of about 1000W may be ()
A. Television B. incandescent lamp C. washing machine D. air conditioner
A. The power of TV set is about 100W ~ 200W, so a is not in line with the title; B, the rated power of incandescent lamp is generally less than 100W, so B is not in line with the title; C, the power of washing machine is generally between 300W ~ 400W, so C is not in line with the title; D, the power of air conditioner is generally larger, about 1000W, so D is in line with the title
If the normal power of a household appliance is about 2kW, it may be?
A. Electric fan
B. Television
C. Air conditioning
D. Refrigerator
A: About 50W
B:100-200W
C: About 1500-2500w
D:300-600W
So choose C
Know the power of household appliances, how to calculate the current of circuit breaker
Two phase two wire 220 V, the total power of household appliances is 5 kW, how many amperes of high break small
Circuit breaker control (write detailed calculation formula)?
According to the calculation of electrician's empirical formula, 1kW of 220 V electric appliance is about 4.5a, then 5kW * 4.5 = 22.5a, it is recommended to use dz47-c32 circuit breaker
How to calculate the daily electricity consumption according to the power of household appliances?
For example: rated power 100W, power consumption (kW. H / 24h) 0.58
For example: rated power of refrigerator 100W, power consumption (kW. H / 24h) 0.58, how to calculate power consumption 0.58
If the electricity consumption of 1kW electrical appliances is once an hour, then one hour of 100W is 0.1 degree, and 24 hours is 2.4 degree, which is the maximum electricity consumption. 0.58 is the 24-hour electricity consumption of this electrical appliance that has been calculated
Rated power of household appliances
Rated power refers to the output power of the appliance under rated voltage
Beyond this power, the load of the appliance will be exceeded, and there is a risk of damage
Is it true that the name plates of household appliances are marked with the words of rated voltage 220 V?
It shows that the voltage of the appliance is 220 V when it works normally
Copy the contents of three small household appliances nameplates and write down the meaning of each item,
Copy the contents of three small household appliances nameplates, and write down the meaning of each item
Ps-69 electric fan | kfr-35g air conditioner | ok-1.5c electric water heater|
Rated voltage: 220 V | rated voltage: 220 V | rated voltage: 220 V|
Working frequency 50 Hz | working frequency 50 Hz | working frequency 50 Hz|
Rated power 65W | refrigeration rated power 1320w | rated power 880W|
C5422 TV|
Rated voltage: 220 V|
Working efficiency: 50 Hz|
Rated power 70W|
Refrigerator
Power consumption: 0.72kw & # 8226; H / 24h rated voltage: 220V
Refrigerating capacity: 4kg input power: 120W
Refrigerant: R600a climate type: n &; St
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