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Electrical Engineering
Electrical engineering is a field of engineering that deals with the study and application of electricity, electronics and electromagnetism.
23,056 Questions
Effects of moisture on electricity?
In foods, this indicates the percentage of water in the total weight of the food. This exceeds the dry weight, and is a portion of the water used in processing.
In lumber, this indicates the remaining water after drying of the wood. Kiln-dried lumber will normally have a lower moisture content than air-dried.
How much electrical energy does electric fan with a power rating of 100 watts use in 1 hour?
It varies tremendously depending upon the size of the fan and the power of the motor. The best way to answer your question would probably be to look at the back of the fan, or on the bottom. It usually will tell how many watts the fan draws. If it only tell amps and volts, remember that watts = amps X volts. Remember that watts does not have a time component; so to say that it draws a certain number of watts in an hour is not correct. You should rather ask, "How many watt-hours does it consume in an hour?" That is the number of watts times the number of hours that it drew that number of watts.
How do you calculate kw in three phase generator?
Use the following equation, kW = Amps x Volts x 1.73 x pf/1000.
What is the theory for load test on dc compound generator?
Connect the circuit as per the circuit diagram shown in fig1. Keep the field regulator of the motor in the minimum resistance position and regulator of the generator in the maximum resistance position.2. Switch on the supply and start the motor with the help of its starter.3. Adjust the field regulator of the motor such that it runs its rated speed given on thename plate.4. Adjust the armature regulator of the generator to build up its rated voltage given on itsname plates on no load.5. Note down the no loads of ammeter and volt meter in tabular form.6. Increase the load gradually in steps and tabulate the readings7. Plot the external characteristics is load current Vs terminal voltage.8 Connect the generator for differentially compounding, repeat the process and plot theexternal characteristics.
746 watts = 1 HP.
Another Answer
To some extent, you are trying to compare apples with oranges. A horsepower is simply the Imperial unit of measurement for power which, in SI, is measured in watts. So you can only convert horsepower to watts. There are 746 watts in one horsepower. The volt ampere is used to measure a different quantity, called 'apparent power', which is simply the product of the supply voltage and load current in an a.c. circuit. To convert apparent power to power (or 'true power'), you need to know a third factor, called 'power factor', which is the cosine of the angle by which the load current lags or leads the supply voltage.
What size cable should be used for a 3phase 10kw Air Heater?
To answer this question the voltage of the unit must be given.
Can you run a 5000 btu AC with a ProForce 2500 generator by Coleman?
Hi:
You got a bonifide good question on your hands there. No kiddin, And , A good question deserves a good answer. This, Is something I'm going to attempt to do for you.
- 1,,, lets for a moment, ( assume ) that the Coleman generator that you call a ProForce 2500 is in fact a
2500 watt rated generator at lets say,,, 115 V.A.C. 60 cycle and that none of this output ability is divided say amongst several various plugs you can choose from at the generator output. So again,,,, we are ( assuming stuff ) like,,, 115 volt 60 cycle single outlet 2500 watt max. output rating for your generator. By the way ::: I hate assuming stuff , K , it not good design criteria. A good saying is, You are only as good as your information you have to work with. BUT:::: bye golly !!! I do like your question.
- 2,,, Look at the tag on your A.C. and see if you are dealing with say 115 volt A.C. 60 cycle current in the first place. ( Probably is, But!, Make Sure! )
- 3,,, Look at the tag on your generator and do the same as
you just did in step 2.
- 4,,, You probably wont be lucky enough if your like myself
and see the wattage consumption plainly written anywhere on your A.C.. So look for something on there that indicates amps usage. basically, you know it'll be somewhere below 15 and almost certainly less than 20. There are reasons for this such as, design critirea that the A.C. must meet to be passed by government codes and to get U.L. approval. ( U.L. = Underwriters Laboratorys ) it is pretty much a mandated minimum requirement which has to be passed for electrical devices to be sold here in the U.S.A. Once again ( Assuming ) you are in the U.S.A.,, LOL Repeat procedure with the generator.
- 5,,, 2500 watt pretty well in its simplest form ,, ( I
said simplest form!!!! K,, ) don't go nailing to a tree alright. Again in its ( simplest form ) 2500 watt rating on the generator will mean roughly 25 Amps rating with a pure resistive load. Resistive is the key word here K. What you have with your A.C. is something a wee bit different. It's basically what is called a ( inductive load ),,, which is basically saying it is a motor you pluggin into that thing. This does complicate things a bit, However, we not going any deeper on that.
- 6,,, Look and see if that generator has a maximum surge
current rating. And also a duty cycle, which is basically how much work it can do as compared to its maximum rating. A wee bit of a rule of thumb,,, The total A.C. load ( all its power pulling components combined ) should not be more than 25% of the surge current rating and definetely not more than the continuous duty cycle rating for the outlet you are plugged into for your voltage requirement on your generator.
- 7,,, There are yet still other things to take into account
when designing around generators, ( But !!! ) we gonna keep it simple as possible. Your generator will probably operate the A.C. in question. But you may see that it runs into a bit of trouble when the A.C. cycles on and off. This is that inductive thing at work against you. You see,,, A inductive load can pull many times its rated running power rating in amps at start up.
Answer simplified: You cuttin it thin, and I don't think the Coleman Co. would be to comfy with this minimal margin for that particular generator. To be certain though, Call em up and ask them the same question you just asked me. Hopefully they'll have a toll free number for you to use, Cuz it might take awhile.
Jimiwane question. Running a A/C on GeneratorA 18 cf refrigerator uses 600 watts of power. Should be no problem running your ac
An A/C load is different than a one from a refrigerator...
you can 'run' the small 5,000 window unit (3 or 4,000 btu even better, LG makes a 3,000 unit...) with a small genset, even down to about 1kw or a bit more. the problem is, as stated above, the start cycle of the compressor unit needs a lot more 'headroom' than the smaller a/c units can generate (usually). you will wear the little a/c unit out pretty quickly. however, if you're going camping and need the thing for a week or so, by all means go for it. caveat: be careful of using a.c. (alternating current) where it rains, as you don't have any gfci (ground fault circuit interrupter) protection out in the woods! or the lake!!! BE CAREFUL! you'd be better off using a truck bed camper with a room window a/c unit in the front of the cab, stuck out one of the side windows with the cab to bed partition window open to allow air into the bed, using a little plug-in fan to direct the air to you in the bed/camper area. i know. I've done it. it works. at least you have the chassis ground to protect you that way. you'd still need to provide some cover for the genset if it rains though. if you're just looking for an a/c standby at your house, then it'll work, but again the start-up cycling will wear the unit out a lot faster than if it was plugged into an a.c. grid. a Yamaha or Honda is a great choice, as the inverter nature of the unit helps immensely with the problems I've outlined above. that comes at a price though. can't have it all - yet. I'm sure something's on the way...
What is 2 pole and 4 pole generators?
Both 2 pole and 4 pole generators are machines which produce electricity. Standard 2 pole versions are cylindrical while 4 pole versions use squirrel cage rotors.
How does us standard 208-120 AC voltage differ from standard European 415-240 AC voltage?
Generally 220v anything works easier or with less effort so can be cheaper to run. Appliances that run off 240V draw less current than 120V appliances so lighter wiring and fixtures can be used. However, 240V is more prone to arcing than 120V. Also, 240V is more likely to blow you away than 120V, whereas 120V is more likely to "grab" (Cause your muscles to involuntarily contract, i.e. making your hand grab a conductor) you. Also the US uses 120V because Edison originally used 100V. It was upped over the years to cope with demand. The US also has 240V in residential service for large appliances like ovens and dryers.
Why open circuit test show only core losses?
With the secondary not supplying any load, there is no secondary current and the primary current will be a low-value magnetising current. So, the copper losses, (I2R) will be insignificant.
How much voltage does a window ac use?
The quantity you're looking for is current, measured in amps. Electrical appliances are generally rated by power (P, in watts) which is related to voltage (V, in volts) and current (I, in amps) by Joule's law:
P=V*I
So to calculate current, I=P/V, you need to know V and P. Voltage is 120 V in the US and 230 V in Europe/UK, and you'll have to look up the AC unit's power from it's label.
Why meter ampere was connected in series and voltmeter was connected in parallel in a circuit?
An ammeter is used to measure the current through a circuit and thus it must be in series with that load. Also, it's resistance is so low that it cannot be connected in parallel since it will result in a short circuit.
A Voltmeter is intended to measure the voltage across a circuit and thus it must be connected in parallel. It has a very high resistance such that connecting it in series with a circuit will lender the circuit useless or inoperative.
How does a normally open contact work?
An electrical switching device that in it's normal rest state does not conduct an electrical current. To become conductive an external force must be applied to change, (switch), it's physical state from open to closed.
What are the different electrical precautionary measures?
When working with electricity, always err on the side of caution. Disconnect the power source and place your lock on the breaker. Double check the disconnection before beginning work. Use tools made to insulate from electrical shock.
Can you convert three phase 480 volts to single phase 110 volts?
If you have a 220v three phase delta system, the phase-to-phase voltage is 220v single phase; hence, no conversion is necessary. Don't worry about 220-240v rating, the voltage rating is nominal. Your 110v single phase has actually already be taken from a center-tapped transformer on your three phase system.
What happens to the current when the ammeter position is changed in a series circuit?
it gets a bigger chance of giving wrong result.
ANSWER Absolutely not in series the meter will read the same no matter where it located in the series circuit. the same meter cannot be placed in parallel to measure.
How do you calculate the occupancy load in spa?
To calculate the occupancy load in a spa, you typically use the formula: Occupancy Load = Area of the space (in square feet) divided by the occupancy load factor specified by local building codes, which varies based on the type of space. For spas, this factor may consider areas like treatment rooms, waiting areas, and pools. It's essential to refer to local regulations for the specific load factors applicable to your spa's design and services. Always ensure compliance with safety and health guidelines.
What one is better fuse or circuit breaker?
IMO it would be because the circuit breaker has the possibility of going bad and not working (allowing a short to move through the device), but fuses blow (cause a break) no matter what if shorted.
How does a step up transformer work on a three phase system?
A step up transformer takes a specific input voltage on the primary coil and induces a specific higher voltage on the secondary coil, hence the name step-up. The secondary voltage is determined by the ratio of turns on the secondary to primary coils respectively.
For example, a transformer with 100 turns on the primary and 1000 turns on the secondary will produce a secondary voltage that is 10 times the primary voltage.
For a more in depth explanation of how transformers actually induce voltage on the secondary coil, see the link below.
You will most likely see a 'step-up' transformer on neon signs. The next time you're at a restaurant or bar, look at their neon sign. You'll see a black box (4" x 4" x 6"w) connected to the sign (usually). This is the transformer, and it takes 120 volts AC and steps it up to 7500 to 10,000 volts AC. This excites the neon gas and causes it to glow.
A step-up transformer transforms voltage to a higher level. Like 120 volts to 277 volts. It is type of transformer which is used to step up the voltage from low to high value in order to make it applicable for high rated appliances. Not only for high rated appliances but also for transmission in power distribution systems. It is critical in this role. Power distribution systems depend heavily on step-up transformers to generate the high voltages needed for more efficient long-distance power distribution. (And yes, there are step-down transformers at the other end to make the voltages more "user friendly" and less dangerous.)
How may amps does a 240 volt 15 hp motor draw?
46A
AnswerAs 15 horsepower is the output power of the machine, you will need to know its efficiency at that output in order to determine its input power. Without that information, you cannot determine its current draw.
Should there be voltage between ground and each hot of a three phase power system?
There are two types of connections in three phase systems. One is a delta connection where there is no connection to ground, so you should not get any voltage to ground. This is classed as a three phase three wire system. In this type of system any one of the phase wires could become grounded and no one be the wiser. Code requires that grounding lights be added to a delta system to visually show what the phase condition is in relationship to ground. The other type of system is a wye or star point connection. This is classed as a three phase four wire system. In this type of connection the coil ends are all joined together and grounded. You would have voltage between the phases and a lower voltage to ground. The voltage to ground would be the phase voltage divided by 1.73.
Yes. If there is no voltage between a hot and a ground, either the hot isn't really a hot or the ground isn't really a ground.
AnswerThere is always a potential difference between a line conductor and ground, regardless of whether it is a three-wire system or a four-wire system. This is due to the capacitance between line and ground.
What happens to an electric current when the wire is made smaller?
Electric current as we usually describe it is the flow of electrons. Current is caused to flow by voltage, which can be looked at as "electrical pressure" that forces electrons to move. Currents can be made smaller or larger by decreasing the voltage across a fixed amount of resistance. As resistance is the quality of "resisting" or "limiting" current flow, we can change resistance to change current. For a give voltage, if we increase the resistance, we can make the current smaller, and if we decrease it, we can make current larger. In electronics, voltage equals current times resistance. E = I x R Also true is that current is equal to voltage divided by resistance. I = E/R As current equals volts divided by resistance, if we change one of them without changing the other, current will change. And in increase in voltage (with no change to resistance) will cause current to go up. The opposite is also true. Also, if we increase resistance (with no change in voltage), current will go down. And the opposite is true here, too.
What does a ammeter measure and what units does it use?
It measures current flow in amps or milliamps. It needs to be in series with the current flow or in the case of a clamp-on meter it must encircle the single conductor carrying current.
