Symbol Standarisation P&ID For Industri Standard piping and instrument symbols are detailed diagrammatic documentation that provides a set of forms & standards for documenting P&IDs and PFDs, including standard shapes for instruments, valves, pumps, heat exchangers, mixers, crushers, vessels, compressors, filters, motors and other connection forms. Here are some symbols on P&ID : So, those are some of the symbols that we will often see when reading piping & instrument diagrams. May be useful.
Basic Electronic Formulas
Calculating Electric Power
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Here are some formulas that we can use to calculate electrical power:
P = V x I .............................................................................................(1)
P = I² x R ...........................................................................................(2)
P = V² / R ...........................................................................................(3)
Des :
P = Power (watt)
I = Current (A)
R = Resistent (Ohm)
V = Voltage (V)
Formula number 1 can be used to find power if the voltage and current are known.
We can use formula number 2 to find power with known resistance and current.
We can use formula number 3 to find power if we know the voltage and resistance.
Problem example1 :
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The above is an example of a series circuit, calculate the total power?
Answer :
Is known :
R1 = 1 ohm
R2 = 3 ohm
R total = R1 + R2 = 1 ohm + 3 ohm = 4 ohm
V = 6 V
Asked :
P = ... ?
Answer :
P = V² / R
= 6² / 4
= 36 / 4
= 9 watt
Problem example 2 :
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The above is an example of a parallel circuit, calculate the total power?
Answer :
Is known :
R1 = 4 ohm
R2 = 6 ohm
R total = 1/R1 + 1/R2 = 1/1 ohm + 1/3 ohm = 1,34 ohm
V = 24 V
Asked:
P = ... ?
Answer :
P = V² / R
= 24 ² / 1,34
= 576 / 4
= 144 watt
Thus a brief discussion and also some examples of calculations for power in a circuit. Hopefully it's useful.
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