『Formula for calculating the current carrying capacity of wires』Related information(clamp on meter|electromagnetic meter|venturi meterrotameter|orifice meter|ultrasonic flow meter|mass flow meter|coriolis mass flow meter|coriolis flow meter|magnetic flow meter|magmeter flow meter|magflow flow meter|mag meter flow meter|electromagnetic flow meter|vortex flow meter|turbine flow meter|thermal mass flow meter|thermal flow meter|rotameter flow meter)
What is the current carrying capacity of a 1.35 square meter cable? 1. The working current of the motor is about 110A, and a 35 square millimeter copper cable can be selected.
2. Calculation process:
1. Rated current calculation: I=P/1.732Ucos Φ=55/1.732/0.38/0.8=50/0.53=104.45A.
.2、 If it is close range (within tens of meters), the copper wire is 25 square millimeters and the aluminum wire is 35 square millimeters.
3、 If it is a long distance (over 100 meters), the copper wire is 50 square millimeters and the aluminum wire is 70 square millimeters.
4、 If it is between a long distance and a short distance, the copper wire is 35 square millimeters and the aluminum wire is 50 square millimeters.
3. The mnemonic for calculating the current carrying capacity of a wire: Multiply 2.5 by 9, and subtract one from the top in order.
. Thirty five times three and a half, in pairs, subtract five points. Conditions are subject to change and conversion, with high temperature copper upgraded at a 10% discount. The number of pipes passing through is 2-34, with a full load flow of 876.Fourth, the calculation method of rated current and its application in special cases: The rated current is generally calculated by the following formula: Rated current=rated power/rated voltage (I=P/U) Rated current I=The rated current of a three-phase motor refers to the line current of the motor power supply introduction line. For star connected motors, the line current is equal to the phase current, and for delta connected motors, the line current delay is equal to three times the phase current of the root.
. Therefore, the formula for calculating the rated current is as follows: P - rated po
Fifth, Selection of Rated Current for Reactors:
1. Reactors have almost no overload capacity, so reactors for main transformers or outgoing circuits should be selected based on the maximum operating current of the circuit, rather than using normal continuous operating current.
.2、 For the reactor of the segmented circuit of the power plant busbar, the current that may pass through the reactor when the largest generator is cut off due to an accident on the busbar should be selected. Generally, 50% to 80% of the rated current of the generator is taken.
3、 The segmented code macro circuit reactor of the substation busbar should meet the requirements of the users primary load and most of the secondary load. 6、 Selection of rated current for split reactors:
1. When used in the generator or main transformer circuit of a power plant, it is generally selected at 70% of the rated current of the generator or main transformer.
2、 When used in the main transformer circuit of a substation, the maximum load current passing through the arm with the higher load current should be selected. When there is no load data, it is generally selected at 70% of the rated current of the main transformer. 7、 Mnemonic explanation: The mnemonic in this section does not directly indicate the current carrying capacity (safe current) of various insulated wires (rubber and plastic insulated wires), but rather represents it by multiplying the cross-section by a certain multiple, obtained through mental calculation. The multiplier decreases with the increase of the cross-section. 8、 The above formula is based on the condition
Hot News
Related AD
