Wanted: basic electricity lesson

[fridayman]

Can anyone point me at an online tutorial for electricity equations i.e.current=volt*amp type info. I want to understand exactly what my split charge system will be doing and what the practical meanings are of all the ratings on each bit.

 

[Jon Wildsmith]

The power equations should be all you need for calculations e.g. P=V*I (power in watts = voltage in volts * current in amps) which you can transpose into I=P/V (current in amps = power in watts / voltage in volts) and V=P/I (voltage in volts = power in watts / current in amps).

can't help you with a site for general electrickery information though.

 

[fridayman]

The power equations should be all you need for calculations e.g. P=V*I (power in watts = voltage in volts * current in amps) which you can transpose into I=P/V (current in amps = power in watts / voltage in volts) and V=P/I (voltage in volts = power in watts / current in amps).

can't help you with a site for general electrickery information though.

Lesson 1

 

[fridayman]

Lesson 2:

A shunt (aka a current shunt resistor or an ammeter shunt) is a high precision resistor which can be used to measure the current flowing through a circuit. Using Ohm's Law we know that the voltage dropped across a resistor divided by the resistance of that resistor is equal to the current, therefore if we measure the voltage across a shunt resistor in a circuit, we can easily calculate the current.

Resistance = voltage / current

 

[Jon Wildsmith]

I didn't think you'd want that equation but to go with lesson 2: V=I*R (voltage in volts = current in amps * resistance in ohms) transposes into I=V/R (current in amps = voltage in volts / resistance in ohms) and R=V/I (resistance in ohms = voltage in volts / current in amps)

 

[fridayman]

I didn't think you'd want that equation but to go with lesson 2: V=I*R (voltage in volts = current in amps * resistance in ohms) transposes into I=V/R (current in amps = voltage in volts / resistance in ohms) and R=V/I (resistance in ohms = voltage in volts / current in amps)

I have a Reya battery monitor that can monitor up to 4 battery banks - giving current draw, capacity and temperature for 2 of the banks. It only comes with one shunt though (to measure the current draw - see lesson 2 ), so I was reading up on what it is. Now I know I need another one.