The following are common units and their abbreviations. Note that unit abbreviations are case-sensitive. While some units can be understood when written incorrectly, some have a completely different meaning if the wrong case is used. Avoid any possible confusion or ambiguity and use the correct case.
A - amps, a unit of electric current. Named after André-Marie Ampère.
V - volts, a unit of electric potential. Named after Alessandro Volta.
W - watts, a unit of power. Named after James Watt.
Ω - ohms, a unit of electrical resistance. Named after Georg Ohm.
h - hours
k - kilo (SI prefix for 1000)
K - Kelvin, a unit of temperature. Named after William Thomson, 1st Baron Kelvin. Not really relevant in solar discussions.
m - milli (SI prefix for 1/1000)
M - mega (SI prefix for 1000000)
Current is measured in amps - A
A battery's voltage is measured in volts - V
A battery's current capacity is measured in amp hours - Ah
A battery's energy capacity is measured in watt hours - Wh. Wh is simply Ah x V. Many times it is shortened to kilowatt hours - kWh. Example: 5120Wh or 5.1kWh.
An inverter is measured in watts - W. Many times a value is shortened. 4000W can be written as 4kW. Really large systems could be in megawatts (MW) or even gigawatts (GW). Small electronics might be measured in milliwatts (mW).
A wire's resistance is measured in ohms - Ω. Many times the resistance is very small such as 0.002Ω commonly written as 2mΩ (two milliohms).
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AC vs A/C - AC is alternating current. A/C is air conditioning
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While not a unit, one common abbreviation that should be written correctly is for Lithium Iron Phosphate batteries. The correct written form is LiFePO₄ though most people find LiFePO4 is much simpler to type. LFP is a shorthand abbreviation understood in the context of this forum when discussing batteries.
Incorrect abbreviations would include LiFePO (lithium iron phosphorus oxide), LiFePo (lithium iron polonium), LiFePo4 (lithium iron tetra-polonium), LiFeP04 (using a zero instead of a capital O), LiFe (lithium iron), LifePo4 (wrong case on the F and O).
Note that there is a lithium-ion polymer battery typically written as LiPo. That is not at all the same as LiFePO₄. You do not want to confuse the two types. Though both of those types are specific examples of the more general lithium-ion (Li-ion) batteries.
A - amps, a unit of electric current. Named after André-Marie Ampère.
V - volts, a unit of electric potential. Named after Alessandro Volta.
W - watts, a unit of power. Named after James Watt.
Ω - ohms, a unit of electrical resistance. Named after Georg Ohm.
h - hours
k - kilo (SI prefix for 1000)
K - Kelvin, a unit of temperature. Named after William Thomson, 1st Baron Kelvin. Not really relevant in solar discussions.
m - milli (SI prefix for 1/1000)
M - mega (SI prefix for 1000000)
Current is measured in amps - A
A battery's voltage is measured in volts - V
A battery's current capacity is measured in amp hours - Ah
A battery's energy capacity is measured in watt hours - Wh. Wh is simply Ah x V. Many times it is shortened to kilowatt hours - kWh. Example: 5120Wh or 5.1kWh.
An inverter is measured in watts - W. Many times a value is shortened. 4000W can be written as 4kW. Really large systems could be in megawatts (MW) or even gigawatts (GW). Small electronics might be measured in milliwatts (mW).
A wire's resistance is measured in ohms - Ω. Many times the resistance is very small such as 0.002Ω commonly written as 2mΩ (two milliohms).
--------------------------
AC vs A/C - AC is alternating current. A/C is air conditioning
--------------------------
While not a unit, one common abbreviation that should be written correctly is for Lithium Iron Phosphate batteries. The correct written form is LiFePO₄ though most people find LiFePO4 is much simpler to type. LFP is a shorthand abbreviation understood in the context of this forum when discussing batteries.
Incorrect abbreviations would include LiFePO (lithium iron phosphorus oxide), LiFePo (lithium iron polonium), LiFePo4 (lithium iron tetra-polonium), LiFeP04 (using a zero instead of a capital O), LiFe (lithium iron), LifePo4 (wrong case on the F and O).
Note that there is a lithium-ion polymer battery typically written as LiPo. That is not at all the same as LiFePO₄. You do not want to confuse the two types. Though both of those types are specific examples of the more general lithium-ion (Li-ion) batteries.
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