What's the one main difference between UPS & inverter ? And electrical engineering & electronics engineering ?

UPS is Uninterrup Power Supply, it mean when you got power off or Black out, your electrical power still On for some ceratin time (save power for certain time)

If inverter mean AC to D or vice versa, it just change the type of current of your electrical power, it cannot save power.

Inverter, if it mean drive inverter it just for control the motor speed and/or torque.

Electrical engineers generally deal with large-power applications, such as utility and industrial power systems, whereas electronics engineers deal with low-power systems such as computers and communications. 

Well, I will tell you the main difference between a UPS and an invertor, the invertor will convert the12v into220v through transformer and a small circuit, but it will not charge a battery, while, UPS is an automatic device, that is uninterruptable power supply, it will give you consistent power supply when your main power cut or failure, but it will be limited power supply for you, depends upon the battery size, if the battery Amps are higher then the back up will be higher, if the battery is small, then the back up will be small, but we will have to look over the load on that UPS, for example, if the load is one Fan and one CFL then it would be60watts plus25 watts for a single room, it will be85 watts. A battery of10Amps (fully charged) will give60 minutes (apprx.) back up, if we increase the amps, then the back up will increase, for example, if we use80 amps battery, then12vx80a=960watts, your use is85, then you can get70% of electricity, because30% of battery will not give you accurate current, but volts.

Dear amany mokhtar,

I agree with eng. Deni Jungjunan for ups definintion and usage and to simplify the case we can say the following:

1- ups is such ac/dc converter , battery , smothing circuit and dc/ac inverter.

2- inverter is using same way to control mainly the output frequecy by ac /dc coverter then smotthing circuit and then some thing called chopper circuit to convert from dc to ac with the requested output frequency and the inverter is used to control motor speed.

about Electrical and electronic engineer i totally agreed with Eng. Deni Jungjunan   

thanks,

the main difference between the UPS and inverters that the ups takes the ac current and draw it dc current by mean frequency equal to zero 

then keep it as a charge till we need it when the power cut off the release it as an ac current with the same frequency

the inverters take dc or ac current and draw it ac current with a large wide of frequencies from zero up to noload  frequency of the motor we wish to control

  the electric engineering means in installation and control by using electronic devices and how to make a well control  , the electronic engineering means in installing and control the chips it self or how to control 

the electronic engineering in manufacturing section to the electrical engineering is like the brain to the muscles