Hey guys..lol.... Are you aware that you have lost the relation to the actual matter already?!? Besides of that it depends on many local factors / infrastructure....better said where one lives... Germans get actually a bonus of 4000 Euros when purchasing an EV, but it must not exceeded 60000 Euros...most Teslas cost far more... An idealist goes with the tech if convinced..money plays always a secondary role..pioneers!
@Yen: IMHO what will happen is that tesla will create a vehicle whose cost is less than that number. Otherwise, they'll lose an entire market. Yup... "Boys and their toys". Girls are no different.
I have to disagree, A/C capacitors are measured in uf (micro-farad) also, and thier purpose is to store a charge, it's how you test an A/C cap. A/C caps come in two flavors, start and run http://www.hvachowto.com/2014/11/12/start-run-capacitor/ A jolt from an A/C cap is not very pretty. A/C caps are also tested in the same manner that you describe the D/C caps. I can't ever recall seeing a cap on a dc motor but 99% of my experiences with motors are A/C. I am a retired hvac service tech
Meantime, in the real (not JFK) world... https://chargedevs.com/newswire/is-toyota-changing-its-tune-10-new-evs-in-the-pipeline/ Is Toyota changing its tune? 10 new EVs in the pipeline https://twitter.com/OEVAorg/status/...f4150d3b5be10&uid=917878446&nid=244 289476609 BMW Achieves Goal Of Selling 100,000 Plug-In Electric Vehicles In 2017 https://electriccarsreport.com/2017...tomers/?utm_source=dlvr.it&utm_medium=twitter Volkswagen delivers first e-Crafter electric vans to major customers https://twitter.com/search?t=1&cn=Z...electrictruck&uid=917878446&nid=244 285282313 https://www.teslarati.com/tesla-sem...f4150d3b5be10&uid=917878446&nid=244 272699400 How Tesla’s Semi will dramatically alter the trucking industry
Yes. Telsa offers already the Model 3. People say there are 400000 preorders already...the price should be ~35000 Dollar. I think an EV should not represent the status of a rich man...rather of an idealist. I can comprehend that people get things and assign their very own personal value to them. When I've got my new stereo or headphones some people could not comprehend why I spent that much money for them... At electricity providers I have an ideal as well...only 100% renewable....higher price does not matter to me.. Anyway I'd never buy a 100000 Dollar Tesla
@Joe C: In that particular case, they're not used to store charge, but to provide a phase lag so that the motor starts up correctly. Read here: https://sciencing.com/ac-motor-need-capacitor-start-6596783.html Capacitors in their simplest form are two metal plates separated by an insulator (dielectric) This means that in the presence of DC, except for a brief instance (5 time constants), the capacitor is a short circuit. After that, it's an open circuit. AC however, is rapidly changing polarity, so there is a current flow through the capacitor. Both frequency and the value (in micro farads) determine the phase lag. In a simple capacitor circuit, the voltage lags the current by 90 degrees (pi / 2 radians) In a simple inductor (coil) circuit, the voltage leads the current by 90 degrees. Just about every engineering student remembers "ELI the ICE man". The phase lag in a capacitor is incredibly useful in filters and timing circuits as well. Here's a link discussing basic capacitor theory. https://learn.sparkfun.com/tutorials/capacitors/capacitor-theory For those of you who remember Calculus, the transfer function for a capacitor is C*dv/dt
I'm not going to get into an in-depth discussion, but next time you see a start cap for an A/C motor, touch it and you'll know what I mean. Then tell me it does not store a charge Spoiler: zap Although you may have the power disconnected to the air conditioner, these components are designed to hold electrical energy. Without discharging the capacitors, you can easily electrocute yourself. http://homeguides.sfgate.com/discharge-air-conditioner-capacitor-29302.html
@Yen: Myself I'm all about living within my means. My purse is a $10.00 Wal Mart special. I would not spend hundreds of dollars on a designer bag. But I would put the money into a good pair of headphones. @Joe C: I've been in the electronics industry for more than 30 years, so I'm no stranger to charged capacitors. And I keep a clip lead and a high wattage resistor on my bench to to discharge any power supply caps (which is what you're supposed to do.) In very high voltage caps, there's a shunting strap across the leads of the cap to prevent it from picking up and storing electrostatic charge. Bcos charge iz charge, and you can get knocked on your ass by one of those caps.
Yes, many newer A/C caps now have what they call a "bleed resistor" to discharge slowly. It keep sloppy service techs from getting zapped and they do not have to buy new test meters too. Shorting out one of these caps ( like they used too) with a bleed resistor will kill the resistor, as a hvac tech, your supposed to carry a bleed resistor with you (alligator clips) so you do not kill parts your not supposed to kill, and safely discharge the cap
@Joe C: The easiest way to get electrocuted is to not show electricity the respect it deserves. There's also inductive 'kick' which can really smart you. Even at lower voltages. In DC relays, there's a reversed diode across a relays' coil terminals. This diode effectively removes the inductive kick. This explains what I mean: https://www.coilgun.info/theoryinductors/inductivekickback.htm
There is nothing wrong with what you've said. Actually there are no AC and DC caps. There are caps and they have different attributes and behavior at AC and DC. To charge one you need DC. I mentioned 'natively'...it needs one particular direction it behaves just like a battery with fixed poles.....electrons flow until the cap is charged. Then the cap closes...from the perspective of the circuit the circuit gets open. At AC it behaves like a capacitive reactance... its plates get periodically charged positive and negative simultaneous to the frequency. Current gets the same frequency, but a phase delay... MJ is right. It is no ohmic resistor since the two plates are isolated...there is no flow-through-it The probability that an cap on AC is partially charged is very high and you can feel that of course... You referred to usage at AC as motor capacitors..the major purpose is to delay/change phase though. I referred to the native function as storage to deliver on demand...flash light, defibrillator.... I have to admit I struggled with correct translation.... at an open circuit there is no current....the cap closes since it has got full capacity (farad), is fully charged.
@Yen: Take a look here. https://electronics.stackexchange.c...like-a-short-circuit-during-a-current-impulse https://en.wikipedia.org/wiki/RC_time_constant The first paragraph explains the DC response of a capacitor.
Larger A/C motors do need a phase change not only to start, but for better efficiency too. 3 phase motors need no caps
JFK wishes those capacitors had bleed resistors under the distributor caps on the farmall H's and M's back in the 60's and 70's. Perhaps his handwriting would be better today if they had. @Joe C, Ever feed "normal" 220 to a 3-phase 208 motor, spin the shaft an let it run, and then wire another 208 3-phase motor into those 3 leads ? Poor Man's 3 phase generator that is.
The only time I worked on 3 phase motors were always 460/480 volt, didn't spend any time to play. How could you wire a single phase 220v to a 3phase motor?
You only hook the incoming 220 to any two of the 3 leads of the first (208 volt) motor, What works good is using an old pull cord from a broken lawn mower wrapped around the shaft of that first motor, apply the 220, pull hard on the pull cord to initially spin the shaft, once that is happening it will generate the third leg on it's own. So to power another 208 volt motor you would use all 3 leads coming out of the first motor, the two 220 leads and the one lead not connected to anything. Edit to add, 30 years ago (GOD, Has it been that long ago ?) I successfully powered a Bridgeport milling machine and a set of steel rolls in this manner in a building without 3-phase power.
Sounds crazy...lol I wonder instead of a pull cord you could use a start cap with a current relay (called a hard start kit), The start cap gives the motor the extra amps (a lot) to get going but once the motor gets going the back emf feeds into the relay (normally closed switch), energizing it to open the circuit to the start cap and drops it out (before if fries the winding's) A/C compressors do this start cycle all the time, because the motor starts under a heavy load (high psi on the piston, worn bearings or too much drag on the cylinder wall)
Doubtful. When you first apply the single phase 220 it just sits there and does a 60 cycle hum. Once you pull the cord, the inertia of the spinning shaft gets it over the "hump" and it begins spinning normally..( my "primary" motor was a 10 horse rated at 1650 rpm (I think) And that is the RPM it spun up to....) and generated it's own 3rd leg.