Simple 3P load question

[rookie4now]

There are 4 9Kw HVAC units (36Kw total). The service is 120/240 3P. I thought the current would be (I=36,000/(240*1.73)) which comes to 86.7 amps per leg. When I plug it in to the load calculator, it comes up with 50 amps. While I'm on the topic, what are the total available Kw on a 300a 120/240 service?

thanks

 

[augie47]

If it's 50 amps, we are both overlooking something.

In a balanced situation the 300 amp service would be rated 124.5 kw (not taking continuous vs non-continuous into account)

 

[Smart $]

... When I plug it in to the load calculator, it comes up with 50 amps. ...

What load calculator?

 

[rookie4now]

If it's 50 amps, we are both overlooking something.

In a balanced situation the 300 amp service would be rated 124.5 kw (not taking continuous vs non-continuous into account)

Do you also show 86.7 amps as the HVAC load?

Thanks

 

[rookie4now]

What load calculator?

There is a power calculator at http://www.watlow.com/reference/tools/3phase.cfm

 

[Smart $]

... what are the total available Kw on a 300a 120/240 service?

In a balanced situation the 300 amp service would be rated 124.5 kw (not taking continuous vs non-continuous into account)

Can't rate in kW without more info. With provided info, 124.5kVA.

 

[david luchini]

There is a power calculator at http://www.watlow.com/reference/tools/3phase.cfm

You asked the calculator to give you the resulting "phase current."

If you ask it for "line current," it gives you 86.6A as the answer.

 

[Smart $]

There is a power calculator at http://www.watlow.com/reference/tools/3phase.cfm

Well I can tell you right off the bat that I wouldn't use those to calculate motorized equipment. You need the power factor to calculate Watts. Without it, the best you can calculate is Volt-Amperes

 

[dicklaxt]

Throw out the 50amps and everybody is right,,,,,rule of thumb for a ballpark quickie 1KW=1HP=1KVA