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Yes, you can use a 40 amp breaker to feed a sub panel. The wire from the 40 amp breaker must be #8 or larger. If you intend to use the full 40 amps a larger conductor must be used. Conductors can only be loaded to 80% capacity in continuous load conditions. A #8 wire is rated at 45 amps x 80% = 36 amps. The suggested size would be a #6 rated at 65 amps x 80% = 52 amps.
It is not recommended to use a 40 amp breaker to feed a sub panel, as the breaker size should be based on the size of the wire and the load of the sub panel. It is important to follow the manufacturer's guidelines and local electrical codes when determining the appropriate breaker size for a sub panel.
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What would happen if a 200 amp breaker is used in a 100 amp sub panel?
There are two things to think about here. First of all a 200 amp breaker will not physically fit into a 100 amp panel. This is so designed because the panel buss is not designed to conduct 200 amps before the current is cut off. A 100 amp rating on the panel is the maximum amount of current that the manufacturer states, that can be handled safely. Second if the 200 amp breaker is in the main panel then everything downstream from that breaker has to be rated for 200 amp conductivity. The wire size will have to be 3/0 from the breaker to the first over current device in the sub panel which will be the sub panel's main breaker. The sub panel can not be a load center but will have to be a combination panel. I doubt that the 100 amp sub panel's main breaker lugs would be large enough to connect the 3/0 cable.
Can you feed a 60 amp sub panel from another 60 amp sub panel?
Yes, you can feed a 60 amp sub panel from another 60 amp sub panel as long as the total connected load does not exceed 60 amps. Make sure to properly size the wire and protect the circuits with appropriate breakers to ensure safe operation of the sub panel.
Can you had a 20 amp breaker on your 70 amp sub-panel that has already 70 amp total on it that consist of one 50 and two 15 amp breakers and the panel has 4 available spaces out of 8?
SeeIf_a_100A_breaker_panel_has_five_15A_breakers_and_four_20A_breakers_could_this_overload_the_panel
Can a sub panel from a 15 amp breaker be used with a branch circuit with 20 amp breaker?
Answer for USA, Canada and countries running a 60 Hz power supply service. Yes you can add these two breakers to the sub panel. You will have to keep in mind the fact that if the total loading of the two breakers exceeds 30 amps the 30 amp sub panel breaker will trip. If you use the 20 amp and the 15 amp loads individually then you will be under the 30 amp feeder sub panel breaker and good to go. With feeders of 3 conductor #8 the 30 amp breaker can be increased to 40 amp. If there are large motor loads involved this answer will change as starting current has to be calculated into the equation. View discussion page for additional information.SAFETY ADVICE Before you do any work yourself,on electrical circuits, equipment or appliances,always use a test meter to ensure the circuit is, in fact, de-energizedIF YOU ARE NOT REALLY SURE YOU CAN DO THIS JOBSAFELY AND COMPETENTLYREFER THIS WORK TO QUALIFIED PROFESSIONALS.
Can a 60 amp main breaker be used to supply a 100 amp subpanel power so that I can take advantage of the extra curcits provided by the larger panel I'll only be using 45 amp at any time?
It is not recommended to use a 60 amp main breaker to supply a 100 amp subpanel. This can lead to overloading the main breaker and potentially causing a fire hazard. It's important to match the ampacity of the subpanel to the main breaker for safe and efficient operation.
What size breaker do you use for a 100 amp sub panel?
A 100-A sub-panel would be fed from a 100-A breaker.
What would happen if a 200 amp breaker is used in a 100 amp sub panel?
There are two things to think about here. First of all a 200 amp breaker will not physically fit into a 100 amp panel. This is so designed because the panel buss is not designed to conduct 200 amps before the current is cut off. A 100 amp rating on the panel is the maximum amount of current that the manufacturer states, that can be handled safely. Second if the 200 amp breaker is in the main panel then everything downstream from that breaker has to be rated for 200 amp conductivity. The wire size will have to be 3/0 from the breaker to the first over current device in the sub panel which will be the sub panel's main breaker. The sub panel can not be a load center but will have to be a combination panel. I doubt that the 100 amp sub panel's main breaker lugs would be large enough to connect the 3/0 cable.
Can you feed a 60 amp sub panel from another 60 amp sub panel?
Yes, you can feed a 60 amp sub panel from another 60 amp sub panel as long as the total connected load does not exceed 60 amps. Make sure to properly size the wire and protect the circuits with appropriate breakers to ensure safe operation of the sub panel.
I have a Transformer 480 primary 208 secondary feeding 1 200amp mb 42 space panel I need to feed a subpanel 6 ft away I'm thinkin feed through lug at top of bus or at feed through MB suggestions?
The sub-panel need to be fed from the main panel, by way of a circuit breaker connected to one of the breaker locations. Or if your sub-panel has a main breaker installed you can feed from the main panel with a sub-feed lug kit. This looks like a breaker, but is only a point where you can branch off the sub panel.
How do you wire a garage sub panel box from a 100 amp breaker in the house main panel?
you propaly can't sub panel from 100 amp panel. Just not enough amperage to be worth while. i had to up grade t a 200 amp main first and then I was able to take a 60 sub panel from that.
Can you put a 60amp breaker and a 50amp breaker on a 60amp subpanel just as long as they are not being used at the same time?
You can. Using these size breakers in a 60 amp sub panel might be pushing the limit for breaking the sub panels feeder breaker. The breaker feeding the sub panel will have to be no bigger than 60 amps because of the main bus bar capacity of the sub panel. It would be better to install a 100 amp sub panel and then there would be a bit of a buffer and you will have the ability to add additional small load circuits.
Can you had a 20 amp breaker on your 70 amp sub-panel that has already 70 amp total on it that consist of one 50 and two 15 amp breakers and the panel has 4 available spaces out of 8?
SeeIf_a_100A_breaker_panel_has_five_15A_breakers_and_four_20A_breakers_could_this_overload_the_panel
Can a sub panel from a 15 amp breaker be used with a branch circuit with 20 amp breaker?
Answer for USA, Canada and countries running a 60 Hz power supply service. Yes you can add these two breakers to the sub panel. You will have to keep in mind the fact that if the total loading of the two breakers exceeds 30 amps the 30 amp sub panel breaker will trip. If you use the 20 amp and the 15 amp loads individually then you will be under the 30 amp feeder sub panel breaker and good to go. With feeders of 3 conductor #8 the 30 amp breaker can be increased to 40 amp. If there are large motor loads involved this answer will change as starting current has to be calculated into the equation. View discussion page for additional information.SAFETY ADVICE Before you do any work yourself,on electrical circuits, equipment or appliances,always use a test meter to ensure the circuit is, in fact, de-energizedIF YOU ARE NOT REALLY SURE YOU CAN DO THIS JOBSAFELY AND COMPETENTLYREFER THIS WORK TO QUALIFIED PROFESSIONALS.
Can a 60 amp main breaker be used to supply a 100 amp subpanel power so that I can take advantage of the extra curcits provided by the larger panel I'll only be using 45 amp at any time?
It is not recommended to use a 60 amp main breaker to supply a 100 amp subpanel. This can lead to overloading the main breaker and potentially causing a fire hazard. It's important to match the ampacity of the subpanel to the main breaker for safe and efficient operation.
Is a 12 gauge wire on 20 amp breaker safe for a sub panel?
No, a 12 gauge wire is rated for 20 amps, which matches the breaker size. It is not recommended to use a wire that matches the breaker size as it can result in overheating and potentially cause a fire hazard. Consider using a thicker wire, such as 10 gauge, for the 20 amp breaker to ensure safety for the sub panel.
Can you have a 40 amp breaker with feeding a 100 amp shop panel. I have about 30 feet of 8 wires 4 between the two.?
No, the breaker should be sized to protect the wire. For a 100 amp panel, you should use a 100 amp breaker with appropriately sized wires for the distance to ensure safety and proper functionality. Using a 40 amp breaker with 8 gauge wire would not be sufficient for a 100 amp panel.
What is the largest sub panel you can install off from a 60 amp main panel fed by 100 amp service?
You can install a 100 amp sub panel off a 60 amp main panel fed by 100 amp service. This allows for the sub panel to be adequately powered with headroom for future circuits or expansions. It is important to ensure the wire size from the main panel to the sub panel is sufficient to handle the load.
