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"40 C" means 40 degrees CENTIGRADE temperature rating.
The breaker is rated to warm up to this temperature while in use without risk of fire or breakdown. It should not be used in such a way that it exceeds that temperature.
Note that wires connected to the breaker must have an equal or higher temperature rating of its insulation. However, when the wire insulation rating is greater than the breaker rating, the wire's capacity must be determined using the breaker's lower temperature rating.
For example:
If the breaker is 400C and the wire is 400C, the wire capacity would be based on 400C
If the breaker is 400C and the wire is 600C, the wire capacity would be based on 400C
If the breaker is 600C and the wire is 900C, the wire capacity would be based on 600C
I don't believe this to be true... The breaker is tested to and calibrated at the 40c rating. (This has more to do with ambient temp. than the way the breaker is being used) In a case where the temp. may exceed this rating you may trip before seeing the current the breaker is rated. The wire is typically rated @ 75c & 90c and the connection point on the breaker or the lug would be rated @ 60c
The above paragraph is correct It is the ambient rating of the breaker calibrated to trip at that temperature set point. In cold climates this has to be watched very closely. On a -20 C day, on breakers that are exposed to the elements, a breaker on the overload portion of the tripping mechanism may not trip until the current reaches one and a half times the handle rating.
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What gage wire is used for a marina shore power 100 amp circuit breaker?
0 or if it a main breaker in a service entrance you can go down to #2 <<>> A #3 copper wire with an insulation factor of 75 or 90 degrees C is rated at 100 and 105 amps respectively.
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There is no need to write a C program for circuit analysis; there are lots of packages out there that already do that (for example, Spice).
Limitation of logic converter in analyzing digital circuit?
The answer is C.
What is the Internal circuit diagram of crystal oscillator?
Ans. A series L R C in parallel with C' .
What are the advantages and disadvantages of a gas circuit breaker?
The advantages of a circuit breaker are: they are smaller in size than fuses better versions may have electronic trips so they can adjust trip curve to suite circuit design easier for end user to reset (no touching live parts) no waiting to reset (as with fuses - spare must be found) no cost associated with resetting unlike cost of replacement fuses easier when ground fault protection is needed The disadvantages of a circuit breaker are: they are more expensive than fused switches when a circuit breaker trips, you lose all power (with fuses you only lose that phase) harder to coordinate fault selectivity harder and more costly to obtain high short circuit interrupting capacities
What is a Circuit breaker and explain type circuit breakers?
A circuit breaker is a switching device which can make,brake and carrying (or trip the circuit) that specified over currents for a small interval of time . There is a different types of Circuit Breaker's are there 1.According to their arc quenching media these are divided into 4 types a) Oil circuit breaker b) Air blast circuit breaker c) SF6 circuit breaker d) vacuum circuit breaker 2. According to their services the circuit breaker can be divided as a) Outdoor Circuit Breaker b) Indoor Breaker 3. According to the operating mechanism of circuit breaker they can be divided as a) Spring operated Circuit Breaker b) Pneumatic Circuit Breaker c) Hydrolic Circuit Breaker 4. According to the voltage level of installation these are divided into 3 types a) High Voltage Circuit Breaker b) Medium Voltage Circuit Breaker c) Low Voltage Circuit Breaker.
What Wire Size needed for 40 amperage circuit breaker?
A #8 copper conductor with a 90 degree C insulation factor is rated at 40 amps.
What is the fullform of M C C B?
moduldcase circuit breaker
What is the max load on a 30 amp breaker?
The maximum load on a 30 amp breaker is 30 amps at 40 degrees C. If the ambient temperature is higher that 40 degrees C then the breaker will trip at a lower current. Keep in mind the breaker is a dual function device. On a short circuit the magnetic component will trip the breaker instantaneously. If you are designing a branch circuit for a load that is constantly on, code may require you to "derate" the branch by 20 percent so that the ordinary load is not at the rated load of the overcurrent protection.
What size wire for a 40 amp breaker to a welder?
A #8 aluminium wire with an insulation factor of 90 degrees C is rated at 45 amps.
Can an electric range be powered from the same circuit as an electric dyer?
No. The two appliances usually have dedicated circuits. The range will have a two pole 40 amp breaker and be fed with a 3-C #8 copper cable. The dryer will have a 30 amp two pole breaker and be fed with a 3-C # 10 copper cable. As you can see by powering a 40 amp device from a 30 amp breaker, full operation of the range will trip the 30 amp breaker.
Can a 40 amp breaker not a 4 amp breaker be used to replace a 35 amp breaker for ac unit?
Depends on the size of the wire going to the A/C. If the wire is AWG #10 you cannot install a 40 amp breaker. If the wire is AWG #8 you can.
Do circuit breakers trip more easily in humid weather?
Ambient temperature has an effect on the tripping point of a breaker. If a breaker is operating at near capacity the additional ambient temperature will lower the breaker trip set point. As to humidity making the breaker trip easier, the answer is no. Humidity makes the ambient temperature seem hotter that the true temperature is. A standard operating temperature of breakers is from from -5 to 40 degrees C. If the breaker is used at higher temperatures than 40 degree C they have to be de rated, 50 degrees C to 90% and 60 degrees C to 70%. The standard humidity rating of a breaker is 85%. Humidity that is constantly higher than 85% will require a special tropical environment type of breaker that extends the humidity range up to 95%.
Can I use my old central air conditioner's circuit to power a new hot tub?
The capacity of the breaker in amperage and the size of the wire connected to the breaker of the A/C circuit must be stated along with the total load of the new hot tub. Only then can an answer be given.
Why does a new AC in a new house throw the outside circuit breaker once a week?
If the breaker only trips once a week you may have a bad breaker or the breaker may not be large enough for your A/C unit. You should also have an electrician look for any loose connections from the unit to the breaker panel. (It is not uncommon to have a bad breaker)
Your breaker won't stay on and continues to flip when ac unit is on i've changed circuit breakers out didn't work then upped them from 40 to 50 what should you do?
Please call an electrician before you burn your house down! Changing a 40A breaker to a 50A breaker will eventually melt your wire's insulation and start a fire if it continues to trip. I would say you should change it back, but you should let the electrician do that. There is a short or overload in that circuit, which needs to be corrected before you attempt to reapply power. Circuit breakers are not there to make your life harder, they are there to make your life longer! Have a professional electrician correct the short or overload and then replace the breaker with a properly rated breaker before energizing the A/C unit.
What cancels out a c-c-c-combo breaker?
Nothing cancels out a c-c-c-combo breaker. The combo breaker prevents the opponent from continuing their combo, if they kept on trying for a combo.
