The next generation of techs will be much more ethical and efficient with access to good training like this!

62 years old. I have been in the HVAC Trade since my early Teens in my Dad's Marine AC Biz. I am now Manager of Technical training for Home Serve USA and found all your Videos to be a great resource. And accurate.

For being in the trade for 36 years... I must say you have a great channel and us old dogs still learn something every day.

As a long time boiler operator and now moving into my company’s HVAC / electrical group this information is gold! Never stop learning and challenging yourself to master new skills!!!

More of these types of videos please Bryan. Great stuff man.

If we want a trade to be ethical we must train and promote a question friendly atmosphere. Providing content like this allows those seeking the knowledge to get what they need. Thank you.

Wow, THIS was the Best CLASS yet…!!! ✅ That was a Good breakdown of the subject at hand 🤚 so far.

Great!!! One of the fundamentals of capacitors is understanding they (many types) are rapid discharge devices. Several decades ago in electronics school, it was cool to see the spark when leads were shorted together. Yes, safety first, but we did learn a few pranks/tricks.

A meter could check the capacitance by putting a AC test charge on the capacitor and measure the phase shift in the circuit. It could also measure the voltage rise rate and /or decay rate over a resistive circuit. When an ac capacitor is installed on an AC circuit, the voltage of the capacitor is dependent of the current "pumped" into the capacitor, since the voltage would change direction before the current could completely build up the charge it would always lag the source voltage. This lag is really represented by the line resistance. The more line resistance, the more the lag.

This was both informative and entertaining. No interest in becoming an HVAC tech, but I think I'm going to watch all your videos.

Very good instructing, made very plain and simple.

This dispels so many myths about discharging caps And how they work. Your helping not only customers to put more faith in the trade due to good workmanship but helping techs do their job safely and with professionalism. I’m sure you’ve saved the life of a young tech somewhere for sure. most companies don’t offer any training but rely on senior techs to do that for them. you give a great resource for those guys and gals lol. Great resource. I refer you to all new and old techs. And installers for that matter. 😏👍

Man, you guys got to be one of the BEST.... tech schools out there thanks for the lessons and keep them coming.

There's a channel Ludic Science that has a video 'Making a High Voltage Capacitor' out of 3 disposable plates, a couple pieced of aluminum foil and baby oil. Very good if you need a visual of what makes a capacitor. They just roll something like that up in the can for run caps. Also, his 'Electrical Reactance Demonstration' video is the best for seeing how inductors/windings and capacitors act like resistors in AC series circuits.

I'm not sure why this video was I my feed today,but I'm absolutely ectatic after two years of not being able to figure out why my air compressor wasn't working properly.. I had replaced the start capacitor a year ago ,cause it kept blowing the breaker when I tried to turn it on. Well I was having a issue with the parts guys about getting a new run capacitor,and I don't have a credit card s online wasn't happening, well after watching this video I got my voltage meter went down stairs to the thing ,and low and behold someone had put the wires on the one terminal on the run capacitor,I switched it not knowing which one went where,but it fired up and kept going!wow! I'm very happy. This was a compressor that someone had given me cause it didn't work 👌🙂👌it's a 6hp 27 gallon🙂 ps I'm now a subscriber!

Nice job instructing. I’ve been a radar design engineer for over 30 years and it amazes me how many engineers lack those fundamental concepts.

Well done. We're always learning. Thanks again.

Awesome stuff. Much appreciated. Thanks for sharing this. It is VERY helpful.

Thank you for your great video Best instructions ever to learn on line

Very much appreciated. Learning made interesting.

excellent .. thank you for making this kind of videos.

Thanks for the video, it is great learning the wiring of compressor and fan capacitors. Way back in the 80s when I worked on cars, one of the practical jokes was to take a ignition capacitor and charge it with a spark plug wire and the lay it somewhere where you know someone would pick it up and of course it would shock them :-)

I will make only one comment, a board being able to be marked with dry erase marker showing the circuit path is such an advantage teaching students this theory, or any theory is very helpful. I listened to you but wished I was there to clarify by drawing the circuit path to aid in your teaching. Great job in your explanation I must add but adding drawing’s really helps solidify their understanding in theory.

Some good info about capacitors per se, not much at all about their function as run caps in AC motors - or how to diagnose bad ones - symptoms of failing / failed parts.

So far I'm up to 4:20 and I gotta say, my hairs are standing on end. I feel like I just struck gold here. WOW ! ! !

What a capacitor does with an induction motor is create another line phase. A capacitor connected to AC makes the voltage lag. This is handy with single phase motors to give you phase angle to develop torque. You're sure not using the capacitor to store a charge while a motor is connected to line voltage. There's plenty of charge on the line all the time.

I was taught that in a sine wave, the amps lead the volts which means they do not happen at the same time, so they are essentially out of phase. A run capacitor works to put the amps and the volts in phase and this gives a running motor much more torque.

Great information. Thanks

The capacitor meter Measures the curtentxtime to get qoulombs at its test voltage. Then calculates capacitance.

No professional HVAC experience here. Great instruction and your principles are solid (from this old electrical/ electronics guy). Especially at the end: RMS 120VAC = 170 V-Peak

super class give us an other one we love it

Great video! Packard Capacitor Training video on UKposts is helpful too.

The first thing that should have been talked about in this class is how to safely discharge the cap.

I've heard that standard reasoning, of back EMF from the motor causing higher voltage drop across the upstream capacitor, but I think it's not accurate. It's a confusing topic because there are two kinds of back EMF, the kind of reverse voltage that comes from the motor acting as a generator, and the kind that comes from inductive properties of the coils inside the motor. I think the higher drop across the upstream capacitor comes from the inductive properties, not the generator effects. You can easily model the higher drop across the upstream capacitor with an A/C series LC circuit. At resonant frequency you get huge drops across the cap, since electrons are shifted back and forth between capacitor and inductor like a juggler tossing a ball. That's why it is so important to have the correct run cap in line. The circuit needs to be tuned to resonant frequency. On the other hand, the generator effects of the motor cause a reverse voltage (in phase) which can never exceed incoming voltage. A reverse voltage charging the downstream side of the capacitor would tend to increase voltage on the downstream plate, effectively reducing the drop across the capacitor plates. Unless the generator effects are out of phase, you shouldn't see big voltage drops across the capacitor coming from pure generator effects.

Lots of thanks sir Your videos are really good and helped

PFM LOL! I think “the math” is probably based on this equation. Amps x 2652 / Volts=MFD. For example you can check a capacitor on a running system without disconnecting by measuring the amps on the start wire multiplied by the constant 2,652, and then dividing that number by the voltage across the capacitor terminals. This trick comes in handy in situations when shutting the system down is not an option or when using a meter that doesn’t measure MFD.

You are mixing start and run capacitors, even though at one point you stated they aren't the same thing. A run capacitor allows a 3 phase delta motor to run from single phase supply. The capacitor is connected across one winding, the line across another. The combined inductance of the winding a d the capacitor phase shift the voltage on that winding by 120 degrees ie a second phase. The 3rd winding is subject to line minus run capacitor winding, which is equal to the equivalent of the 3rd phase. A start capacitor is used in an induction motor that has 1 main winding and an auxiliary. Without the start capacitor it is 50 - 50 which way it will run at each start. The addition of another (smaller) winding and a capacitor means that the motor will always run the same way.

Thx HVAC S for an informative and interesting video brought back memories of '70s Mt Sac College and Mr Motter's Aviation electronics class driving home Xl and Xc calculations to match capacitance to reactance to improve delivered power factor in a motor. Now days a Micro Aire soft starter does it all for me on my RV ACs allowing me to run 2 ACs from 30amp 120vac shore power. Sub'd

The meter is actually acting as a very high impedance path, that's why it is slowly discharging. If it were low impedance the cap will discharge rather quickly.

The caps generally have bleed / discharge resistors fitted just as a side note

Nice video. I tend to think of a capacitor as a mini, fast recharging, UPS. It smooths and boosts voltage when large motors kick on and run, helping them operate more effectively. Since they cycle so much, they do have a lifespan and are one of the more common components to fail. Just the nature of the design and their purpose.

I like Your class.

good source of info .

RPM-run/power to the marked side, never seen one. Understand the marked side terminal is the plate closest to the housing and would short to the can and kick the breaker.

Don't know why the algrorhythm gave me this video but this channel was a instant subscription for me. Thanks for the content.

Did you do the capacitor test ?? with AC voltage . What were the results

Great video but maybe i missed it, question... I realize it's been 2 years since you did it But... say you had a capacitor that was out of the tolerance by far yet the compressor does start up... is it possible that that out of tolerance capacitor would cause the compressor motor to work harder, leading up to thermal overload protection activating on the compressor after it's been running for a while during the day?

New to the field. I was told replace cap. If system works after then is was cap. If that doesn’t fix then it’s motor. Providing there is actuallypower. Labor wise, does it make sense to go through all this?

Thanks for a great video. I just subscribed so I can watch more of them. I know nothing about HVAC, and don't plan to watch 2 videos and then run out and electrocute myself! I would just like to know a little more about how it works and be able to understand what the tech is telling me when they come to maintain or repair it. Thanks again for sharing 😊

Thanks for the video =)

I've got a new 25mfd AmRad cap, it has a black and a white terminal, no other markings, which would be common? Or does it matter?

I can't get to coils to check / clean unless I take it apart even more quite extensively than I have so far and so I guess I'm going to try replacing blower motor capacitor . Coils sitting on top of furnace and I would have to cut freon and drain lines . Yes it might be very dirty but don't wnat to go further and capacitor is only $12 . That might work ?

Volt meters are high impedance devices, like in the mega ohms. Current meters are low impedance.

High impedance for voltage; low impedance for current. @12:10 ish or so.

It's very simple explanation easy to understand thanks alot

Great video..

Always good info.

Really wish I work here man so much knowledge

Thanks for demonstrstion

rumor has it they're still putting out the fire from that off-camera test

The run capacitor creates a 90 degree phase shift in current when properly sized for the load with ac going through it. This causes a rotating magnetic field around the rotor.

I have a coleman RV ac on the compresser start capacitor with a resistor in the one wire it is bad as well,, my question is do I need the resistor OR can I do away with it ??

good teacher ,admitting he don't know everything but that is how he was taught and just passing along his knowledge.

Where can I get the alligator clip meter leads that you guys were using in the video? I don’t care for the ones that came with my Fieldpiece meter so I bought some Amprobe alligator clips which look similar to the ones in the video but much larger. And by much larger I mean way too large. I like the ones in the video, they look like just the right size for me

There's a wide range of capacitors.Those are starting capacitors filled with electrolyte.Some are ceramic or use other materials.In a circuit a capacitor will block DC but not AC.It will phase shift the AC signal.RMS (root mean square) voltage is 0.707 of peak AC voltage.Some things aren't explained in the video,but otherwise good presentation.

Love it.

Great video!!! I looked in a condenser unit and it had a dual cap with a 60 MFD herm. Looking on repair clinic the model showed it should use a 30 MFD. The 60 MFD was out of spec but must have been in this unit for years. Should I replace with the 30 MFD? I did not look on the compressor unit itself but need to do that too to see if the MFD is noted on the compressor. Trane model TTD760B100A2. Thanks!!

Am Rad, built in Palm Coast Florida. I only use them.

ThankYou

Very helpful class 👍

Hello I have a120volt 1hp motor single phase do I need a capacitor to transfer power from house current to generator so the motor doesn't stop using a 4000 watt electric generator Thanks bill

I need some assistance concerning a capacitor. I am replacing a capacitor that reads 370/440. My replacement capacitor reads 370 VAC. Can I use it. The other question: if only 240 volts are going in why is it use for a max of 440 volts. Finally, a capacitor test is in mfd. so why is voltage a concern or a measurement for a capacitor. Thanks for your support.

*QUESTiON* CAN WE USE A RUN CAPACiTOR iN THE PLACE OF A START CAPACiTOR? ARE THEY iNTERCHANGEABLE?

check into what an "R C time constance" is

In the case a capacitor has common, herm and fan, but fan is not connected on a fully functional condenser unit, what information about the fan can be assumed? Does the fan simply not require a capacitor? 1:38

Awesome! I’m a hvac technician now.

In 1973 a very bulky expensive meter was needed to test capacitors. You could test for opens or shorts with your ohm meter but you couldn't test the MFD's .

Hey I wanna see that last experiment. 😂

Pretty good learning experiment I done worked on heating and air conditioning for over 20 some year I've had my experience with some capacitors the worst I ever had was start capacitor I've had them blow the electric box completely up they're dangerous you ought to teach them about them things . They act like a half a stick of dynamite when they go off got to teach them how to wire them up.

In a microwave oven a capacitor and a diode is a voltage doubler circuit. The 2000 volts becomes 4000 volts...technically you are right the capacitor itself doesn't boost voltage. But in a circuit with a diode it can double it.

Thank you!

Very nice presentation.... Very clear explanation

Can I use a 10+5% in place of 7.5+5% for my indoor blower motor. Just for a day.

You need to a video within the next week before my final exam lol!!! A video on how the electrical is hooked up on a wooden simulator board thing in our classroom showing the wiring from the the thermostat to the transformer, contactor, heat relay, indoor fan relay, compressor, electric heat, indoor fan and outdoor fan!! I bet you $100 bucks you can't make this electrical video with a week!! Really lol 🤷‍♂️

Capacitors store charge electrostatically while Batteries store charge chemically in the form of ions in solution.

The meter has high impedance when measuring voltage...not low impedance. This makes the discharge go slowly

Does it matter at all if you replace a 30 uf with say a 50 uf?

I stupidly didn't pay attention to the color of wire coming out of the starter capacitor on my washing machine before I disconnected it so now I don't know how to tell which side gets power and which side connects to the motor. Now there is a diagram on the side of the capacitor, but I can't seem to find anybody mentioning how this pertains to which side is power in and which side is power out. Is the side showing the coil power out?

What were the details of the dangerous test that they wanted to do? I couldn't hear what the bad idea was. Are you not able to connect 120v to the capacitor using a switch, then turn the switch off, and then measure the voltage?

question: If a cap is fed AC120V and unplugged , then measured would the maximum voltage read be < 60V? since is the difference between the Hot and Neutral. will only be charged up by half of current as it alternates?

Great video! Question: Should you always discharge the cap before you perform the capacitance measurement? Thanks!!

I'm not positive you are correct about the capacitor charging and discharging based on the supplied electrical frequency. I'm pretty sure once charged they stay charged until that charge is used. I can't think of anything in the motor circuit that would discharge the capacitor. In my understanding a start capacity is used to smooth and supply a constant voltage to the motor, and to absorb the start in rush current. I'm open to be informed otherwise.

where can i find those alligator clips off that meter?

I wish fieldpiece meters would display OL. I don't have one. I've been using a UEI. But that's a little petty thing I don't like lol

Which alligator leads are you using, i cant find them on amazon?

you can safely do that last a.c. experiment using a low voltage on the secondary of a transformer!

Still need these with soft start?

Lol in electrical class in college I was the guy in the back who would take the little capacitors from our little electrical circuit builder kit and get everyone to pas thier 9v batteries to me connect them in series and then Hook the cap to the battery bank as the instructor was talking and suddenly hear a sizzle a bit of smoke and bang the cap pops and launches pieces of itself and obviously everyone is now looking at me as I laugh my ass off

Some confusing moments in this video, wanted to clarify.. Start winding need a start capacitor which is usually disconnected by a centrifugal switch. The start capacitor is usually of large value and short time rated. Run winding requires a run capacitor which is always connected to the power in series and continuous rated.. The higher voltage that you measure across the capacitor is because of the LC circuit impedance. You will also measure higher voltage across the run winding for the same reason. Not because of the motor back EMF It is because of this the capacitor must be purchased with the voltage as per the defective unit and not based on supply voltage. Start and run winding should not be confused. All capacitors in market will have a higher capacitance value than the nameplate. If the measured value is less than nameplate value by more than 10%, needs a replacement soon. The run capacitor provides a phase shifted current on the run winding with respect to the main winding, creates a rotating magnetic field which turns the rotor. Regards.

Can these also be checked with a capacitor tester, The sane kind used in electronics?