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Ballpark estimate is 110 amps for 120V and 55amps for 240V.

There's more to it than that though. Depending on the load you'll have to derate the circuit.

This is true. Depending on the devices, the breaker is sized on 125% of the continuous loads ( runs for 3 hours or more) plus the noncontinuous. (This is a rule of thumb for most circuits!!! Obviuosly this isn't always the case, for example, motor circuits)

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โˆ™ 2015-07-17 17:38:34
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Q: What size circuit do you need for 20 devices with consumption of 640W per device?
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What size wire do you need to use to run 200 ft and have 40 amps of service?

To answer this question a voltage must be given. By using the term service I will draw a conclusion that it is a North American service of 120/240. A #6 copper conductor will limit the voltage drop to 3 percent or less when supplying 40 amps for 200 feet on a 240 volt system. If the circuit voltage is 120 volts, then a #2 copper conductor will limit the voltage drop to 3 percent or less when supplying 40 amps for 200 feet. <<<<>>>> Notice: The following calculations are wrong because a #10 copper conductor is only rated at 30 amps NOT 40 amps. To compute voltage drop (independent of voltage supply) 10 gauge wire is .9989 ohms/1000 ft to go 200 feet you need 400 ft of #10 conductor (out and back) just about 0.4 ohms I*R =E 40a*0.4Ohm =16v lost in heating the wire ( 640W ) Gauge Drop(400') #10 16v #6 6.3v #2 2.5v safety has to do with the insulation 3.4 Watts/ft will melt most plastics (#10) especially if its enclosed in conduit or worse in a wall that is insulated. bare conductors on ceramic insulators dont have a problem if this is for a resistive load the figures are correct if you are trying to run a single phase motor it may not start with #6 (starting current perhaps 7 times the running current) 45V drop if you are trying to start a 3 phase motor with #6 it may be ok only (19V drop) I do know a 7A 240V submersible well pump will not run with #10 wire (200' deep well 150' from the building) The wire coming out of the pump is #12 BTW (sales engineering) it is a GOOD idea to do some arithmetic before buying the wire.... the motor is marked with KVA class (start/run current)

How are the safety devices in an electrical circuit connected?

In series with the device.

What does a dedicated circuit mean?

No other devices connected to that circuit other than the device its dedicated to

How can short circuit damage devices?

It depends if the short are before or after the device. The short circuit will cause high amperage trough the device and then blown. (JP)

Is there a device that reduce a fuel consumption in a car?

No, there is not. There are lots of devices that claim to reduce fuel consumption but none of them actually work. Not one.

What is the difference between series circuit and parallel circuit?

A series circuit is one in which the current must pass through all the electrical devices in the circuit in turn. A parallel circuit is one in which the current passes through each electrical device on the circuit following separate, independent path from all other devices on the circuit, one for each electrical device.

What circuit protector?

It is usually classed as a device that will open the circuit if the current in the circuit goes high. Two examples of these types of devices are fuses and circuit breakers.

What are the most commonly used safety devices on a circuit?

After a switch the most common safety device is a fuse or circuit breaker

What is the effect of a short circuit on other devices in the circuit?

It depends on where the over current protection is located in the circuit. If the protection is the first device in the circuit everything connected to the circuit will stop operating. If a connected device has its own protection and that device faults that fuse will disconnect the device but the rest of the circuit will remain on. Just remember that the lowest rated fuse in a circuit will open first in a fault condition.

Which current is used for electronic devices?

It depends on the amount of resistance, or load, the device is on the circuit. Do you have a particular device you're asking about?

What is reduction in electric consumption?

It is the reduction of using electrical devices. Each device is rated in watts. Cutting back on the use of these devices will reduce the watt consumption that is metered at the utility meter. The reduction of electrical wattage consumption will result in a savings of money to you.

A circuit contains two devices that are connected parallelif the resistance of one of these devices is 12 ohms and the resistance of the other device is 4 ohms the total resistance of the two device?


Device that breaks the circuit if the current goes high?

There are two devices that will serve this purpose. One is an electrical circuit breaker and the other is an electrical fuse. Both devices are sized to protect the wire in the circuit from a high current rush of a short circuit.

What integrated circuit device controls USB devices connected to a USB port?

Host controller

How is parallel circuit different from a series circuit?

A parallel circuit is different in many ways from a series circuit: 1. In parallel, the voltage across all the devices connected is the same. 2. If a fault occurs in any device connected in parallel combo, then it has no effect on the operation of the other device. 3. In series circuit the current flowing through all the devices is the same while in case of the parallel one the voltage across all the devices is same.

What safety device switches off dangerous currents?

Circuit breaker, fuse or Ground Fault Circuit Interrupter (GFCI) are three devices that do this.

Normally open devices are wired how?

The wiring of a N.O. or N.C. device is dependant on the function of what is to be done by the circuit it is in. The ambiguity of the question should be more defined as to what the device is and the operation it is supposed to preform in the circuit.

Advantages of parallel circuits?

A parallel circuit can run several devices using the full voltage of the supply, varying the current to the need of each device. If one device fails, the others will continue running normally. If the device shorts, the other devices will receive no voltage, preventing overload damage.A series circuit divides the supply voltage among the devices with a consistent current. If one device fails, all other devices in the circuit will either fail to receive voltage or receive too much voltage and become damaged in the case of a short.An advantage of parallel circuits is increasing the power rating of the circuit and reducing the resistance.

How do you make the electrical devices to consume less electricity?

The manufacturer's electrical design is what causes the device to consume a set rate of electricity. The only thing that a consumer can do to limit the devices electrical consumption is to turn the device off.

What happens when one light bulb burns out in a series circuit?

Series means one device is connected to another device and so forth . for this configuration to work all devices in the circuit must be active in some sort for it to work as a circuit.

What is the definition of a 110v outlet?

It is a point in an electrical circuit where external devices can be plugged into. This in turn will supply the device with the appropriate voltage needed to operate the device.

What is downstream in electrical?

The terminology down stream refers to an electrical circuit and where devices are connected into the circuit. In reference to the breaker that feeds the circuit everything is down stream from it. If a GFCI receptacle is added into the circuit as the first device, the GFCI can be wired to allow all of the regular receptacles to be protected down stream from that GFCI. Every device added to the circuit will be down stream from the one that is ahead of it. The only device that will not have something down stream from it will be the last device in the circuit.

What is a non dedicated circuit?

A "dedicated" circuit is one to which only one device is or can be connected; therefore the circuit is "dedicated" to the device. A NON dedicated circuit will therefore be one to which multiple devices can connect, such as the wall outlets in your home. Multiple wall outlets are connected to a common circuit breaker, making that an example of a non-dedicated circuit.

A device that protects a circuit from current overload is called?

Fuses or circuit breakers are termed 'overcurrent protection devices', which protect circuits from either an overload current or a short-circuit current.

What is the maximum number of devices allowed on a 20 Amp circuit?

The number of devices depends on how many amps each device pulls. If 10 devices pull 2amps a piece then that is your entire 20amps. If your breaker trips then you know you've exceeded the amperage for that circuit.