Dyson digital 95,000RPM motor, trying to connec to a battery

[supak111]

Bought one of their 95k rpm digital motors, took it apart but can't seem to figure out how to run it off an external battery.

Hole where the Dyson OEM battery pushes in has 5 wires/connectors. 2 large ones which are the main POSITIVE and NEGATIVE terminals and then it has 3 small ones. These 3 small ones I can't figure out what they do or how to connect them so I can run the motor of a car battery.

I'm guessing they are to check the batteries temperature, but for a thermistor you only need 2 wires, so still why 3?

Can't seem to find a wiring diagram for this motor anywhere, anyone have any ides as to how I can figure this out?

PS I don't have a dyson battery, wish I did it would make it easier to figure it out.

 

[GreenGiant]

can you post some pictures of the front and back of the motor?

There may be a small controller in the vaccuum that has an enable or something similar, it may be looking for a specific signal, either way at least one of those wires must be an input or else the whole thing wouldnt work,

Does the motor spin freely when not connected?

 

[(*steve*)]

As far as I can tell, these DC motors are three phase AC motors.

The reason for "Digital" is that it requires some digital logic to create the 3 phase AC signals.

 

[supak111]

Yes sure we they are. There are 3 motherboards, bottom medium sized one is the trigger, one on the motor is the main board, and small one at the top right has a switch on it you push if you want the motor to speed up from 35watts to 70watts. Its like a boost button.

There is actually 7 wires in the pictures. two very bottom wires is just a sensor to make sure your collection bin is on the vacuum cleaner, it think it just needs to be shorted together.

pic 1: http://tinypic.com/r/2rp5n3q/5
pic 2: http://tinypic.com/r/8z00n4/5
pic 3: http://tinypic.com/r/nlz811/5
pic 4: http://tinypic.com/r/70yhkl/5
pic 5: http://tinypic.com/r/4sjg5w/5
pic 6: http://tinypic.com/r/2w4b5av/5

PS. i just went and bought brand new one with battery and all, should be easier to figure it out now.

 

[supak111]

I understand why its digital, but it still runs off a 22v battery so there should be no reason why I shouldn't be able to run it off two car batteries in series

 

[(*steve*)]

2 x 12V car batteries could generate a voltage between 20V (dead flat) and 25.6V (fully charged)

That's probably acceptable.

edit: posting a relevant image here would make it far easier for us to see them.

Like this:

(I only looked at the first 2, so I assume this is the most relevant one)

 

[supak111]

I tried to embed the image like you did but they wouldn't show up.

So the NEW dyson dc31 I bought doesn't even have the small motherboard where the trigger is, there is just a trigger switch there. I though it was bad luck but looking at the wiring on the new one I think I can now cut out the trigger motherboard on mine and simply the motor.

 

[Tom Moore]

I tried to embed the image like you did but they wouldn't show up.

So the NEW dyson dc31 I bought doesn't even have the small motherboard where the trigger is, there is just a trigger switch there. I though it was bad luck but looking at the wiring on the new one I think I can now cut out the trigger motherboard on mine and simply the motor.

I realise that this is an old thread but is there any chance of a picture of this? I have an old DC31 which I am trying to repair and I think the trigger motherboard is damaged, if I could remove it completely that would be ideal. Otherwise does anyone know how to get the motor to run on its own?

 

[supak111]

I was close to getting it to run on just any battery but before I was successful I burned out something on the motherboard lol. I then just ran the motor from an simple cheap rc brushless ESC. They are dime a dozen on ebay

 

[SchrodingersCat]

Hi supak111. I too have a Dyson handheld, a DC31 to be exact. I am also after burning something out on the motherboard :-/

I had it dismantled with the battery connected. Unfortunately The boost circuit board hit off the motor circuit board and ending up frying something judging by the sparks and smoke it made.
I wasnt able to troubleshoot the location of the burnt part. As such, I am looking at an alternative way to get it going again.
Would you mind sharing what spec. brushless motor Electronic Speed Controller (ESC) did you use the end? What was your wiring?

 

[supak111]

You can buy any ESC and a cheap $2 ESC tester to run the fan but it doesn't run right because the fan only has 2 terminals on the coils that run the impeller and ESCs use 3 so I had to modify one of the wires on the coils.

Ideal thing to do would be to run this from a custom circuit with a hall sensor, capacitor and a transistor. I wish I could find a cheap circuit that does this.

Something like this should work,
http://www.ebay.com/itm/3144E-Hall-...Sensor-Module-Magnetic-Detector-/162150667208
I would have to add a large capacitor and a transistor I think...

People on here would know better as to exactly what I would need in the circuit
.
.

 

[supak111]

I'm just now sure what would control the RPM if I was to use a hall, cap, and transistor to run this..?? Maybe the voltage would or the cap size?

PS perhaps I should explain that I removed ALL the circuit boards from the motor, all thats left is the frame, impeller, and the 2 coils that runs the magnet/impeller.

 

[SchrodingersCat]

Thanks for the detailed response supak111. I understand your set-up now.
From trawling some of Dysons marketing blurb online for some factual information, your post and from looking at the board, it appears that they are using a single-phase brushless motor.
http://www.electronicsweekly.com/ma...ms-104000rpm-brushless-dc-technology-2009-06/

Unfortunately, proper Electronic Speed Controllers for single phase brushless motors with one HAL sensor are very rare. I cant find any on ebay, let alone for a 200w motor as rated in the Dyson.

I did find one of my problems though. One of the IRFH7932PbF MOSFETs in the motor H-Bridge was blown. A hole was actually brown through it, as shown in the photo attached. I will order a few of Aliexpress and see if replacing it makes any difference. I dont believe that this is my only problem, as if this had blown as a short across the 24v supply it would have pulled the voltage of the battery pack down, which didnt happen when I was measuring it. If it had blown as an open circuit, The charging and power LED would still be lighting.

The second problem that I found was that I was connecting the two "beg/bin sensor" wires as identified in your photo above together. During my tests, I figured that they were connected to a normally closed sensor switch on the dust bin. From looking at the bin, they are actually connected to two terminals on the hose for powering external brush attachments. Im surpised that I didnt short out the battery pack by shorting them.

This fella gives a good tear down here: https://www.experimental-engineering.co.uk/tag/motor-control-board-reverse/

 

[SchrodingersCat]

I managed to get the battery pack dismantled without damaging it too much. Il attach photos if anyone is interested. I blew the 15amp fuse on the black wire by accident. I had to bypass it with a piece of wire to get it working again. Dyson decide to make the black positive and white negative for some batsh*t reason. This, along the difficulty in opening and servicing their products, informs me that they really do not want you opening these things up.

 

[supak111]

I've managed to open the battery pack on mine too. I ended up using the battery pack for another project actually. I'm gonna look into a single phase esc. If I find anything I'll report back. I actually have two of these fans now, I find them cool because they can spin at a 100k rpm reliable