dwelling Calcultions

[greenhornelectrictian]

I have been studying for the contractors exam with the mike holt text and for the appliance calculations all of the example I have seen do not use the 25% largest motor (step 6) 220.18a when figuring the load? I was wondering why ? thanks

 

[Dennis Alwon]

I have been studying for the contractors exam with the mike holt text and for the appliance calculations all of the example I have seen do not use the 25% largest motor (step 6) 220.18a when figuring the load? I was wondering why ? thanks

Do these appliances have a motor that is larger than 1/8 HP?

 

[greenhornelectrictian]

what if it doesnt give the motor hp just the VA the way I figure a 1/8 hp@120V is 348va ? Would that be right or does it have to say the hp before you use the 25% add on rule for the largest motor ? thanks

 

[Dennis Alwon]

what if it doesnt give the motor hp just the VA the way I figure a 1/8 hp@120V is 348va ? Would that be right or does it have to say the hp before you use the 25% add on rule for the largest motor ? thanks

Often times an appliance has more than a motor as a load. For instance, a diswasher has a motor with a heating load. The Va wouldn't help you with that.

I am not well versed in motors but depending on the type of motor the va could be different even if the HP were the same.

 

[greenhornelectrictian]

Still not sure , so you think if the question doesnt state the motor hp size being over 1/8hp you dont need to add 25% of largest motor ??

 

[Smart $]

Still not sure , so you think if the question doesnt state the motor hp size being over 1/8hp you dont need to add 25% of largest motor ??

Perhaps you should provide one of the examples you refer to in your opening post?word for word. We could speculate on this issue all day?and then some?without a "hard" example :wink:

 

[resistance]

I'm with smart.

Post what you have.....