MBU v3 amperage

[oregonfirefighter]

I am wanting to use 2 of my MBU V3 units close to home and would like to use 110AC with a 24v transformer. Anyone know what amperage they require?

 

[LittleBill]

http://www.proheat.com/PDFs/SL9500.pdf

 

[SCSG-G4]

Output of the GI transformer is 1200 watts. Most of that is used when the MBU's start up. The military generator for use with these units was a 2kw machine. If they have 50 percent efficiency then 1200 watts out means 2400 watts in, 2400 divided by 120 volts equals 20 amps, but that is with six burners going, you only want to burn two burners, a third of 20 is a little less than seven, so your answer is seven amps. I could have just given you the answer without the explanation and your question would have been satisfied. Explaining HOW the answer was derived should give you the insight to be able to answer similar questions in the future, for yourself or others.

 

[oregonfirefighter]

However, these are not 120V AC. They are 24V DC

Output of the GI transformer is 1200 watts. Most of that is used when the MBU's start up. The military generator for use with these units was a 2kw machine. If they have 50 percent efficiency then 1200 watts out means 2400 watts in, 2400 divided by 120 volts equals 20 amps, but that is with six burners going, you only want to burn two burners, a third of 20 is a little less than seven, so your answer is seven amps. I could have just given you the answer without the explanation and your question would have been satisfied. Explaining HOW the answer was derived should give you the insight to be able to answer similar questions in the future, for yourself or others.

 

[ZiggyO]

The calculations still apply--- wattage is voltage times amperage (current).... For example, 1200 watts supplied by a 12 volt source effects a current draw of 100 amps---- that same 1200 watts supplied by 120 volts would be 10 amps


So then, the 1200 watt output at 24 vdc equates to 50 amps for a total of 6 burners or about 8.3 amps per burner........ What SCSG said about efficiency holds true since all transformers have losses in the form of heat, etc. He figured 50% which is a really good buffer...... So getting back to the burners, 2 burners would draw about 16.6 amps at 24vdc or about 3.3 amps at 120volts--- figure the 50% efficiency for voltage conversion and rectification and you effectively double that 3.3 amps to 6.6amps ~ 7amps at 120volts as originally figured......... The reality is that efficiency is in many cases better than 50% and the mbu peaks under the 8.3 amp figure at startup which means that you have a really good buffer for a 2 burner power supply.........

 

[oregonfirefighter]

WOW! They are power hungry!