Also, if the wire gauge doesn't land on a standard breaker size then NEC allows the next sized breaker up. So under normal conditions 2/0 wire is rated for 195 amps. But you'll not likely find a 195 amp breaker. So you upsize it to 200 amps. But also NEC as noted in the document I posted above says 2/0 is rated for 200 if used as a feeder in residential applications
August '24 Chat -- Its too damn hot!!
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Plugged in 2/0, 220V, 200A, 100', to the link you gave,
Cooper has a 1.76% drop
Aluminum has 2.90% drop
3/0 drops to 1.40%/2.3% drop respectively.
Given my wire spec is in-between 2/0 and 3/0 aluminum stranded cable, which definitely meets the voltage drop specs you gave.
I'm sure an inspector would frown upon the whole setup though lol
Me gues residential has a substantially lower "duty cycle " for current demand than a commercial application hence the exception?
Cooper has a 1.76% drop
Aluminum has 2.90% drop
3/0 drops to 1.40%/2.3% drop respectively.
Given my wire spec is in-between 2/0 and 3/0 aluminum stranded cable, which definitely meets the voltage drop specs you gave.
I'm sure an inspector would frown upon the whole setup though lol
Me gues residential has a substantially lower "duty cycle " for current demand than a commercial application hence the exception?
All feeders have a lower "duty cycle" then what their maximum is rated for.
Just add up all the individual breakers and see how much amps it is versus the main breaker. Lighting is normally the only one calculated different as it's on for long duration. So if a panel is a lighting panel you use different calculations. But residential is pretty easy with lower demands
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You've kinda lost me there.. as for avg amp usage...I've put an inductive amp clamp on each line, most I've been able to pull is 60-70A combined. Generally I float 25-30A total between the lines
I was saying, add up all the branch circuit breakers. Lets say you have 20 breakers all rated for 20 amps. Thats 400 amps. But due to the "duty cycle" or how often one individual circuit is pulling maximum current is less then 100%. So there never really will be a 400 amp load on the feeder. So they derate the feeders to handle the average or expected load. I don't recall the calculation to figure it out. But haven't had to remember it as all the panels have the ratings already on the label. Then we calculate the feeders based on the service breaker the feeds the feeders and voltage drop and then temperature
Don't get too hung up on voltage drop as it's a soft rule and not enforced. More of a recommendation then a law. Just need to check if your own jurisdiction has codes for it as some have minimum voltage drop for equipment efficiency. Otherwise if it's not critical then ignore it
Do you know what size fuse/breaker is feeding the panel?
CL-320A meter, this is how I disconnected power to swap panels. it's been like this since we bought the place in '90
🫣Don't touch any more than one wire at a time that includes the box as well or you get aggressively tickled in a painful way
Well it looks like we will never know. So does that directly feed the panel you are installing or does it feed another first?
From the looks of your installation, you just reused the same feeders. Any reason you are questioning this? Seems is you are using the same rated panel then just stick with the same service feed
From the looks of your installation, you just reused the same feeders. Any reason you are questioning this? Seems is you are using the same rated panel then just stick with the same service feed
Exactly. You count up the amperage on all the branch circuit breakers and it will always be more then the main breaker. The average load will always be less. And if it isn't then the main breaker will let you know.
It's really only applicable for commercial applications. Specifically lighting loads. But there are a few others that call for over sizing the feeders. Think places like home depot where they will have a continuous lighting load on for most, if not the whole day. If the load on each branch is high enough the feeders will eventually overheat even if the branche circuit breakers are within their limits. It's rare for residential to have any applications where one would need to take this into account
You forgot PepBoys...
They wanted over 8K for a used, supposed low mile 1.0L turbo engine and another $2500 to install it in the vehicle. I purchased a brand new engine from a local Ford dealer with no discount for 2K and it has 1 year warranty on it. I am also replacing other things like the both T-stat's, Injector O-rings, The coolant over flow bottle and cap. Even with oil and coolant, I will probably still be under 3K.
Just a few weeks ago.
I would have to look it up. The dealer I went to had 3 in stock. But that doesn't mean crap because the one that was in it was less than 2 years old and they are both the latest revision. The first dealer I went to that told me they had stock did not have one and when they looked it up it was on National back order but a couple dealers in the area showed stock.
Why you need one?
Also. Make sure they registered for warranty purposes.
They will beed
The engine serial number
Vin number
Mileage
They will beed
The engine serial number
Vin number
Mileage
Firestone too. We had our corporate account through them my god those guys were bad.
Yes I gave all that. They opened the crate at the dealer to get the serial number off the tag on the valve cover. I gave the vin at the dealer. Then I text the mileage when I got home because I didn't have the exact number.
Do you work for ford? I was trying to figure out where the engine that blew a head gasket was sold. Doesn't show up on car fax.
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