amperage question

[ctgo4it]

Hello everyone,

I hope you guys can help me out again with my beginer electrical questions. I'm really confused about how to figure out the amps in a panel.

This house I inspected has a 200 amp main. When I add up all the breakers in that panel it comes to around 360 amps. That is including a 60 amp breaker that feeds a sub-panel. Now when I add up what's in the sub-panel it totals about 260 amps.

Am I figuring the amps wrong, or is this house totally overloaded?

By the way it's a 10 unit with the one main panel and one sub.

Thanks a lot

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[Scottpat]

This is for a 10 unit apartment building and all they have is the one service equipment panel and a single panel for the units?

[Jim Katen]

Originally posted by ctgo4it

Hello everyone,

I hope you guys can help me out again with my beginer electrical questions. I'm really confused about how to figure out the amps in a panel.

This house I inspected has a 200 amp main. When I add up all the breakers in that panel it comes to around 360 amps. That is including a 60 amp breaker that feeds a sub-panel. Now when I add up what's in the sub-panel it totals about 260 amps.

Am I figuring the amps wrong, or is this house totally overloaded?

I don't know whether or not the house is overloaded, but you're definitely figuring the amps wrong.

To figure out the capacity of the electrical system, look at the service entrance conductor sizes, the service panel rating and the main breaker rating (if there is one). The least of these will tell you how much electricity the service can safely provide to the house.

To find out whether or not the service capacity is adequate for the house, you'd have to do a load calculation based upon how the house is equipped. There are a couple of different ways to do a load calc, but you'll need some practice to be able to do either of them. You can find an easy one in Code Check Electrical.

The sum of the breakers is unimportant because you don't know how much of a load's on each circuit and how much power it draws.

Here's a fun experiment. Get yourself a clamp-on ammeter. Open the service panel in your house and snap that sucker around one of the main service wires. Now go through your house and turn on everything. If it's electrical, turn it on; cooktop, range, dryer, clothes washer, dishwasher, get the water heater to cycle, turn on the AC, blow dryers, stereo, computers, etc, etc. Now go back to the panel and read the ammeter. Switch it to the other leg and switch it to the neutral, reading what it says on each of them.

Let us know what you come up with.

By the way it's a 10 unit with the one main panel and one sub.

Thanks a lot

I'm not sure what that means. Tell me it doesn't mean that there are ten rentals in one house.

- Jim Katen, Oregon

[ctgo4it]

Originally posted by Jim Katen

Here's a fun experiment. Get yourself a clamp-on ammeter. Open the service panel in your house and snap that sucker around one of the main service wires. Now go through your house and turn on everything. If it's electrical, turn it on; cooktop, range, dryer, clothes washer, dishwasher, get the water heater to cycle, turn on the AC, blow dryers, stereo, computers, etc, etc. Now go back to the panel and read the ammeter. Switch it to the other leg and switch it to the neutral, reading what it says on each of them.

Let us know what you come up with.

I will do that as soon as possible

Originally posted by Jim Katen

I'm not sure what that means. Tell me it doesn't mean that there are ten rentals in one house.

- Jim Katen, Oregon

Yup, it's a single structure with 10 apartments in it

[ctgo4it]

Originally posted by Scottpat

This is for a 10 unit apartment building and all they have is the one service equipment panel and a single panel for the units?

as well as 2 50 gallon water heaters, one boiler (apprx 120 years old)with a single thermostat ( located in the basement!) for all the radiators. and they want to know why the gas bills are so high. Don't ask what the roof looked like

[Jim Katen]

Originally posted by ctgo4it

as well as 2 50 gallon water heaters, one boiler (apprx 120 years old)with a single thermostat ( located in the basement!) for all the radiators. and they want to know why the gas bills are so high. Don't ask what the roof looked like

Woof.

When you find yourself doing those kind of houses, it's a sign that you should raise your prices.

-Jim Katen, Oregon

[Scottpat]

Sounds like a real charmer!

[chicago]

Hang on a minute.

Tell me these are rental units.

[ctgo4it]

Originally posted by chicago

Hang on a minute.

Tell me these are rental units.

I hope they get rent for it[^]

it's an out of state investor who thinks he can buy houses, and let them pay for themselves without putting anything into it.

and Jim, I charge a base price and an additional fee for each unit