Why standard voltage matters - a knowledge guide
What is standard voltage?
Standard voltage is defined as 230 phase voltage which is measured between the phase conductors (Phase conductor and neutral conductor)
In single-phase supply, 240v is measured in between the conductors i.e. phase and neutral conductors. And in 3 phase supply, 415v is measured between conductors.
Standard-phase is the voltage that is assigned by the governing body to supply in a specific country.
The standard voltage varies from country to country. Usually, 110v to 220v standard voltage is used in different countries.
In USA and Canada, the standard is 120v while in Australia it is 220v.But many countries use also 220v to 240v standard voltage.In the USA 240v is also supplied for heavy appliances.
Is the standard voltage DC or AC?
Standard voltage can either be Ac or Dc. Because by definition, standard voltage means the voltage which is assigned or contracted to be supplied.
Now it can be said voltage AC is supplied to the countries at some standard values i.e. 120v, 220v, and 240v, etc. Along this, Dc voltage is also authorized by the assigning authorities.
When we buy a battery we see the specs which give the detail about the nominal voltage like 1.2v,12v and 48v.
Is standard voltage the output voltage?
A standard voltage is an input voltage. Because it is supplied to the main power boxes of buildings and houses and it is not converted to operating voltage yet. The Operating voltage is what is functional by equipment.
What is standard voltage in a house?
Standard voltage is different in each country due to different voltage standards.
In the USA, two standard voltages are supplied to the outlets. One is 120V and the other is 240V.120V is supplied for general household devices while 240V is supplied for heavy-duty appliances but most devices are not designed for 240V as it is high voltage.
Some other countries like Canada, Brazil, and Vietnam have also the same standard voltages. But many other countries of Europe have a standard voltage range of 220-240V.
What is the standard voltage of battery?
The standard (Nominal) voltage that a cell yields when it is charged. It depends on the chemistry of the cell.
There are some types of batteries with their standard voltages.
| Chemistry Type | Nominal voltage |
|---|---|
| Zinc-carbon | 1.5v |
| Lifepo4 | 3.2v |
| Nmc | 3.6-3.7v |
| Nicd or NiMH | 1.2v |
What causes low battery voltage?
There are some reasons which cause low voltage in a battery.
1. Dead battery:
A dead battery won’t provide any charge and may result in low voltage.
2. Corroding connectors:
Corroding causes poor connection where the wires are jointed which is responsible for bad connections and results in low voltage.
3. Defected battery terminals:
Corroded or bad terminals can also cause a voltage drop.
4. Overdischarge
The battery runs out due to overdischarge, therefore the voltage is low.
How do I check my battery voltage?
Use a voltmeter or multimeter to check the voltage of your battery.
Carefully attach the red probe of the multimeter to the positive terminal of the battery while the black probe attaches to the negative terminal of the battery. The correct signs must be attached to the relevant terminal.
The multimeter has a LED display to show the reading of voltage. When probes are attached they show the voltage.
If the battery is fully charged the display shows a slightly high voltage than the specified voltage of the battery.
For example, a 12v 200ah LiFePO4 battery will be seen as 12.8v on maximum charge.
If the multimeter shows the same voltage of a fully charged battery as that on nominal voltage then it is time to change your battery.
What happens if voltage is too high or too low?
The operating voltage must be within the limit otherwise, once cross the limit line permanent damage would start occurring.
Effects of too-high voltage:
If ternary Lithium cell voltage is exceeding the typical upper limit of 4.2v, two problems may rise.
● Lithium Plating
Dendritic lithium plating occurs due to the accumulation of lithium ions on an anode where they are deposited as metallic lithium. So overvoltage causes lithium plating which is irreversible and can result in a short circuit between the electrodes
Low temperature is also caused by non-uniform elements due to lithium plating.
● Overheating
Overvoltage can also cause heating of the cell.
Effects of too-low voltage:
Low voltage of cells for long periods results in the breakdown of electrodes.
Anodes: The copper anode may dissolve into the electrolyte. Copper ions dispersed and precipitate as metallic copper. This is very risky and results in short circuits.
Cathodes: Low voltage for a long time, causes the breakdown of the cathode. Which results in capacity loss.
Does higher voltage damage battery?
Firstly, lithium batteries have protection circuits that do not allow overvoltage. Lithium batteries are safely designed and work within the set voltages.
Although the boosting voltage enhances the battery efficiency but going beyond the limit, voltage stresses the safety of the battery.
If charging continues for long period above the specification point then the battery can be overheated and may burst out.
The highest limit for a lithium battery whose nominal voltage is 3.2 volts is the end-of-charge voltage, which is capped at 3.65 volts.
The excessive charging voltage can cause lithium plating due to excessive li ions on the anode leading to a reduction in free li ions.Short-circuiting and overheating occur due to this action.
What are the three types of voltage?
The voltages are classified into three major levels. Which are as followed.
1.High voltage (HV)
It is subdivided into two parts: Extra high (EHV) and Ultra High (UHV)
2.Medium voltage (MV)
3.Low voltage (LV)
Voltage distribution:
High Voltage generators distribute 1000v to 4160v to the heavy load industries and provide backup for an individual grid.
Medium voltage generators produce voltage above 50 and less than 1000v.
Low voltage generators are below 50v.
The purpose of Level classification by governing authority is to improve the maintenance and distribution of power.
What voltage indicates a bad battery?
To check that battery is bad we must have a voltage test. The range of voltage for a good battery is from discharge cut-off voltage to charge cut-off voltage.
If the voltage drops below 10v during a load test on the battery by using a voltage tester, then it is time to change the battery. This voltage is unable to start your car.
One more fact is to be elaborated, commonly low voltage means the battery is not charged properly. The alternator or charger of the battery can also be the culprit for low voltage. But if everything is ok except the battery then the only solution to this problem is to replace the battery.
