How to calculate the power consumption of the display screen

Regarding the issue of display screen power consumption and cable cross-sectional area, this article specifically summarizes the knowledge in this area. We calculate the power consumption of electrical products based on their electrical power, which is how much "work" this appliance does per hour, and this work is obtained by multiplying current by voltage.

However, in practical use, power calculation generally divides loads into two types: resistive loads and inductive loads.

The calculation formula for resistive loads is P=UI, where power=voltage × current

The calculation formula for inductive loads: P=UIcosф， Namely, power=voltage × current × power factor

And our LED display screens are used through switching power supply voltage transformation, which belongs to inductive loads. The power factor cos of its switching power supply load ф= 0.75. Different inductive loads have different power factors. When we calculate the power supply of LED display screens uniformly, we can adjust the power factor cos ф Take 0.8.

1.How to calculate 1 square meters LED screen display outdoor P10 power consumption ?

A.If the driving voltage of the LED display screen is 5V and the driving current is less than 20mA, the maximum power calculation method of the screen body is as follows :

B.The specifications of outdoor LED display screens are: point spacing is 10mm, point density is 10000 points/square meter, each point (pixel) is composed of 3 LED lights: 1 red, 1 green, and 1 blue, with a scanning method of 1/4 scanning.

C.Calculation of display power per square meter: P=10000 (points) X 3 (pieces) X 5 (volts) X 0.02 (amperes) X 1/4 (scanning)=750 (watts)

2.100 square meters LED screen display outdoor P10 power consumption

Power consumption of the entire display screen: P=750 (watts) X100 (square meters)=75KW

3. Full LED screen display Equipment power consumption:

Due to the product loss caused by the mutual conversion of electrical energy, the power is generally increased by 10% based on the theoretical calculation value. The auxiliary equipment between screens (such as air conditioning, fans, lighting, power amplifiers, etc.) also generates a certain amount of power consumption. The power consumption of this screen auxiliary equipment is calculated based on the actual amount (we calculate the following formula based on 5KW temporarily).

P=75KW+7.5 KW+5KW=87.5KW

Therefore, if the total power of the display screen is 87500 watts, the maximum current is:

I=P/Ucos ф= 87500 (watts) ÷ 220 * 0.8 (cos ф）= 318 (A)

However, in general working conditions, the LED on the display screen cannot be lit up for a long time at the same time, so when the user's power capacity is small, a common coefficient formula can be used, which is generally 0.5. So, the above calculation should be rewritten as:

I=P * Common coefficient/Ucos ф= (82500 (W) * 0.5+5000 (W)) ÷ 220 * 0.8 (cos) ф）= 168 (A)

That is to say, the total current value of this screen is 168A. Due to the high instantaneous current displayed by the LED during startup, the three-phase 168A switch cannot be used for the main gate air switch. Instead, a 318A air switch should be used, and 400A should be chosen. Many of our engineers in the same industry have a habit of directly calculating the total power of a large screen using the number of switching power supplies on the entire screen. This method is not standard, and some manufacturers reduce the number of switching power supplies in order to reduce costs, which ultimately leads to power calculation errors.

4.LED screen display Average power consumption:

The power consumption varies due to different playback content. For example, when playing promotional videos with rich colors and predominantly white, the average power consumption is 50% of the maximum power consumption; When playing simple graphics such as text, most of the screen is black, with an average power consumption of 10% of the maximum power consumption. According to normal advertising statistics, the average power consumption is generally 40% of the maximum power consumption.

5.The safety calculation method for copper wire current carrying capacity:

The safe current carrying capacity of a 2.5 square millimeter copper power cord is -28A.

The safe current carrying capacity of a 4 square millimeter copper power cord is -35A.

The safe current carrying capacity of a 6 square millimeter copper power cord is -48A.

The safe current carrying capacity of a 10 square millimeter copper power cord is -65A.

The safe current carrying capacity of a 16 square millimeter copper power cord is -91A.

The safe current carrying capacity of a 25 square millimeter copper power cord is -120A.

If it is aluminum wire, the wire diameter should be 1.5-2 times that of copper wire.

If the current of the copper wire is less than 28A, it is definitely safe to take 10A per square millimeter.

If the current of the copper wire is greater than 120A, take 5A per square millimeter.

FAQ

1. What power capacity generator is required for a 100 square meter P10 outdoor display screen?

(Base on max power consumption 730w/sqm, Average power consumption 300w/sqm )

P10 outdoor billboard screen max power 750W/SQM, 100sqm 75KW, generator requirement 75x1.2x1.25=112.5kw

2. How many main cable input for 100 square meter billboard

(Base on max power consumption 730w/sqm, Average power consumption 300w/sqm )

15 lines main power cables input

The safe current carrying capacity of a 2.5 square millimeter copper power cord is 28A, voltage 220-240, P=UI, estimate 6kw, 7pcs cabinets