How can i run this AC motor - Page 1
Forum section: electronics / beginners

author: sairfan1
author_rank: Frequent Contributor
timestamp: November 30, 2020, 09:13:43 pm
content: Hi, its an AC motor of Ninja Blender BL682 and suddenly it stopped working, I uncovered it and it has AC motor PU9835120-0110-B found motor description herehttps://www.globalspec.com/specsearch/PartSpecs?partid={9316F619-79C8-4B24-B0F9-3C32E36FB48D}&vid=286511&comp=36its a brushed AC motor but thing that confuses me is that other than two (AC +/-) wires connected to its brushes, there are three other wires are connected to its outer coils, like Black (Negative) wire connected to first coil and Brown, Yellow wires are to other coil (Brown/Yellow wires are also connected to Relay), White and Blue wires are directly connected to motor's brushes they are also connected to relays, please refer to images/schematic.When i turn it on, i can see sparks on brushes, lots of buzzing sound from relays, but motor does not move at allThere is also a Triac T2035-H-6I not sure if it could be faulty?Can someone help me to understand how this motor can be tested if its still working?Help to understand how these relays are connected to motor (please look at attached schematic) are they connected to run it in different direction, different speed or just to turn it on/offTriac T2035-H-6I is being used just to turn it on/off motor or something like PWM?anything else can I do to test it.Here is link to video of testing motor

author: bob91343
author_rank: Super Contributor
timestamp: November 30, 2020, 09:30:13 pm
content: Is the shaft free to turn? Are all the coils showing continuity?I think it's just a speed control, the different coil connections.Perhaps the commutator isn't making good contact or it has adjacent segments shorted from metal debris.

author: Benta
author_rank: Super Contributor
timestamp: November 30, 2020, 09:41:32 pm
content: Typical universal motor (series connected stator and rotor). Something's not quite right with your relay schematic.When you only have brush arcing without movement, I'd say that something is wrong with your stator. Windings, who knows?

author: james_s
author_rank: Super Contributor
timestamp: November 30, 2020, 09:44:49 pm
content: My first suspect would be one of the relay contacts. It's also worth scraping out the accumulated carbon from between the commutator segments, I fixed a drill that would barely run and made lots of sparks and smoke, the problem was carbon buildup shorting the segments.

author: Zero999
author_rank: Super Contributor
timestamp: November 30, 2020, 09:49:18 pm
content: Before doing anything else:is it still in warranty?If so, put it back together, as well as you can, hopefully leaving no signs you've opened it up and make a claim. Never bother repairing anything which is still within its warranty period, as it's the seller's responsibility to offer a repair/replace/refund.It's a universal motor, which can run off either AC, or DC and since it's run off AC, there's no + or - connection.Are you sure about the schematic? There are no connections to the power, so it doesn't make any sense.Does the motor ever change direction? Perhaps the relays reverse the motor, in which case they would flip the polarity to either the stator (the field coils( or armature (the spinning electromagnets).The TRIAC for the speed control. If it's failed short circuit, then the motor would run at full speed all the time. If it's failed open, then it won't work at all.My guess is there's a shorted turn, or open circuit in the armature, in which case the only solution is a replacement motor, assuming it's possible to get one for a reasonable price.

author: sairfan1
author_rank: Frequent Contributor
timestamp: November 30, 2020, 09:52:36 pm
content: Yes, shaft is free, and continuity test is also OK,Regarding stability of relay and other circuit i wanted to ensure about motor first, if its running by direct connections then i will further look for circuit, not sure if its a good idea?

author: sairfan1
author_rank: Frequent Contributor
timestamp: November 30, 2020, 10:18:15 pm
content: I updated the schematic with power source, it shows where black and red wires are connected from AC power source,What could be the reason for relay buzzing sound, ? relays are turning on/off very quickly

author: sairfan1
author_rank: Frequent Contributor
timestamp: November 30, 2020, 10:28:10 pm
content: I tried motor with DC 30v power supply and motor is running good,now the question is, how can i run the motor with direct AC power?I tried the motor with 60w bulb in series but nothing happens.What are those Brown and Yellow wires for??

author: Labrat101
author_rank: Unknown
timestamp: November 30, 2020, 10:53:45 pm
content: your diagram is is not drawn out correctly . you are missing a connection .reading between the lines as per your diagram its a 2 or 3 speed and the two relays1 is the speed and the other is the off braking to stop the motor free spinning.If you could update the drawing so it was correct would help .the chances that one of the relays has stuck closed . .You cant run a motor with a bulb in series as it uses 5 to 7 time start torque .Unless the PCB has a soft start circuit included .Brown & yellow is the field windingmeasure the resistance of all the coils and mark them on the diag

author: Zero999
author_rank: Super Contributor
timestamp: November 30, 2020, 11:02:05 pm
content: Quote from: Labrat101 on November 30, 2020, 10:53:45 pmIt should work without any load though and the fact he's managing to power if from 30VDC, indicates it should work with an incandescent lamp in series.

author: Labrat101
author_rank: Unknown
timestamp: November 30, 2020, 11:09:33 pm
content: I guess that you checked the interlock was not faulty . ( safety switch )or not getting closed properly.. just a silly thought sometimes the obvious is over looked.Motors don't like resistive inductance in front .( incandescent lamp in series)in theory yes in practice no

author: sairfan1
author_rank: Frequent Contributor
timestamp: November 30, 2020, 11:23:12 pm
content: There is no issue with safety switches,they do not response at all if switch is open.

author: Labrat101
author_rank: Unknown
timestamp: November 30, 2020, 11:28:19 pm
content: If you could give a bit more info more pictures . the PCB has 3 safety locks one maybea reed and hidden magnetic . anti tamper or child tamper .update what are the resistance betweenwhite to yellowyellow to brownbrown to white

author: james_s
author_rank: Super Contributor
timestamp: November 30, 2020, 11:54:44 pm
content: Quote from: Zero999 on November 30, 2020, 09:49:18 pmI almost never bother with warranties, unless something is brand new and doesn't work right out of the box. I'd rather fix it myself than have to make a trip back to the store, post office or pay return shipping and be out my device for potentially several weeks waiting for it to be repaired.

author: sairfan1
author_rank: Frequent Contributor
timestamp: December 01, 2020, 12:55:59 am
content: white to yellow 2.3ohmyellow to brown 0.5ohmbrown to white 1.0 ohmIt turns on, when i press start it starts and shows count down timer, motor receives current, but no movementthat means at least there is no issue with safety switches,One thing is important, that relay gives a buzzing sound means switching on/off very fast.

author: Jwillis
author_rank: Super Contributor
timestamp: December 01, 2020, 06:03:33 am
content: Those three switches (cocktails , puree , low ) look discolored compared to the other switches on the board . Is that paint or are they burned .

author: james_s
author_rank: Super Contributor
timestamp: December 01, 2020, 06:12:22 am
content: Does the relay get its coil power from that transformerless power supply? Those film capacitors (the big dark brownish thing by the edge) have a tendency to fail gradually as the metalization layer deteriorates. Big Clive did a teardown and repair of a remote controlled plug adapter that had a bad dropper cap.

author: Zero999
author_rank: Super Contributor
timestamp: December 01, 2020, 08:57:49 am
content: Quote from: Labrat101 on November 30, 2020, 11:09:33 pmI think you're talking about induction motors, which can stall and dissipate excessive power, if the impedance of the power supply is too low, but it also applies to too lower supply voltages. This is a universal motor and will be fine run at lower voltages, or with a series resistor. An incandescent lamp has a low resistance, when the power is first applied and should be perfect for testing the motor.Quote from: james_s on November 30, 2020, 11:54:44 pmThat may suit you, but from a moral perspective, I strongly urge people to make claims under warranty. It's not right that manufacturers/sellers should get away with pushing substandard, unreliable goods and they need to be made aware there's a problem with their product!Quote from: sairfan1 on December 01, 2020, 12:55:59 amWhich relay? Is it both of them, or just one of them?Do all the LEDs/displays illuminate properly?

author: Labrat101
author_rank: Unknown
timestamp: December 01, 2020, 01:50:24 pm
content: . The reading don't comply to your drawing .ether both the relay are damaged or you are doing some thing very wrong.As we cant see what you are doing .I would really second what Zero999 & james_s said . return it back to the shop .the motor looks ok but the board has several faults . and I think you are notcapable of this repair . Sorry don't mean to be rude . Box it all up and return it.It will be cheaper in the long run. as what is being said and reading between thelines . the relays have a problem now and maybe the controller as well.

author: sairfan1
author_rank: Frequent Contributor
timestamp: December 01, 2020, 04:02:48 pm
content: Sorry for my bad English, please watch the video i uploaded in question (first section).After i changed a capacitor now relays are turning ON properly, motor is getting power but not moving, please refer to videoI understand to run motor alone i have to connect main wires to both brushes, but i do not understand what are those brown and yellow wires for? and how to connect themYes there was a mistake in schematic, black wire was seamlessly connected to blue wire, i updated in the picture.Its not in warranty, i just took it as challenge so that if at least motor is working i can use it with Arduino not throwing a usable thing as garbage.

author: james_s
author_rank: Super Contributor
timestamp: December 01, 2020, 06:13:32 pm
content: It's possible that the relay contacts have been damaged from chattering while driving an inductive load, that's pretty hard on them. The extra wires are taps in the field windings to allow multiple speeds.

author: akimpowerscr
author_rank: Regular Contributor
timestamp: December 01, 2020, 06:19:24 pm
content: It seems to me that this motor is not defective, the problem is with the control relays.Relay 1 is simply the on / off relay.Relay 2: in the rest position, with contacts from relay 1, it provides dynamic braking of the motor, the work position is the normal operating position.What seems to be happening is that relay 2 is not functioning properly and remains in the off position when relay 1 goes into the on position.It is therefore necessary to change relay 2 and check whether there is no capacitive supply with capacitor X2 (generally between 0.22 and 1µF)If so, also replace this capacitor x2

author: Labrat101
author_rank: Unknown
timestamp: December 01, 2020, 06:37:24 pm
content: Hi , Ok watched your video .That juddering is caused because one of the field coils is in reverse phase .I am trying to think of an easy way to explain how these motors work .As from I can see and your relay 1 as per your diag . is not correct .I suspect,First one of your relay contacts are stuck closed so they are in fact shorting the brown & yellow coil.so the motor does not have a phase direction to rotate . That's why it buzzes , the motor has only 180 deg coil.the field coils top and bottom . It requires 360 deg to rotate .Example:: the field coils are like the magnets in a DC motor .on a DC motor to reverse the rotation of the motor one simply reverses the plus & minus.On an AC motor you have to reverse the phase of the Field coils .even though the relays are clicking 2 of the internal contacts have welded together .Some times works give the relays a hard wack on the top with the handle of a screw driver .may release the contact .. THIS is not a fix and will only last a short time for test only and may or may not work.The best way is to remove the relays and test if the contacts are switching .the out case can be removed on some types of the relays .If both the relays check out ok .. which I doubt .some one posted the same while I was typing .Just have a close look on the inside of the casing there maybe a small schematic (wish full thinking)

author: akimpowerscr
author_rank: Regular Contributor
timestamp: December 01, 2020, 08:10:39 pm
content: The function of relay 2 is not to reverse the direction of rotation of the motor but to provide a dynamic brake for the motor so that it stops more quickly.How does it work?Relays 1 and 2 must be deactivated at the same time.The rotor becomes a self-excited dc series generator by supplying DC power to only one of the two stator coils.It serves also as a low resistance load.Some power is dissipated in this coil and the motor therefore brakes.Relay 2 is not functioning properly and there are several possible reasons:- defective relay (coil interrupted, contacts soldered, etc.)- faulty relay control circuit-supply voltage too low

author: Labrat101
author_rank: Unknown
timestamp: December 01, 2020, 08:33:07 pm
content: Quote from: akimpowerscr on December 01, 2020, 08:10:39 pmI already mentioned that it was for braking in my earlier post #8 further up.I assumed I did not have to repeat(example of how that motor works & could work)I made a few typo's as well

author: akimpowerscr
author_rank: Regular Contributor
timestamp: December 01, 2020, 10:03:57 pm
content: Quote from: Labrat101 on December 01, 2020, 08:33:07 pmWe don't blame you.I just tried to clearly explain to sairfan1 the details of how the motor works as we are in the beginner sectionIt doesn't matter who said what first.The forum is not a place of competition between members, but a place of collaboration between members.