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Currently trying to fix my old coffee grinder. The PCB is pretty useless so i have to build new controller myself. However, my googling has come to a halt as i first need to identify what motor i have. There little to no documentation on the product so i figured id ask some experts..

Please see the attached picture

The sticker attached to the motor has some details, but what motor type these are properties of i have no clue..

If you have any idea of what type this might be, please do tell me how you were able to tell!

img og motor

Thanks!

Edit: Per comment, here are some more picture hopefully showing required details:

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More information from comments:

Problem with old pcb is that it was programmed to trigger a small relay at a fixed interval. Essentially switching the motor on and off about once every second. I need it to run continuously.. Please see my updated post with new pictures. I imaging i could bypass the relay entirely, but what points to connect where i'm not too sure of.

The grinder is of the "automatic type", meaning that its programmed to cycle on after x amounts of portions have been dispersed. This was a primitive and effective system with switches attached to the dispersing system. All of this has been removed, but the programming remains. As i can no longer "toggle" the switch i simply want the grinder to turn on when the power switch is flicked. Simple as that. Would i be able to jump what i assume is a relay? As noted, the one second interval is way too short for what these are rated for(i presume). Could this be signs of a faulty capacitor?

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    \$\begingroup\$ Product repair/usage questions are generally off topic here, and doubly so when missing details. That's an induction motor of sorts, intended to use a 10uF phase shift capacitor at least to start (and probably to run), beyond that... At bare minimum you should add a picture of the wires between the motor and board, and both sides of the board. Why do you say the board is "useless?" Even if damaged plenty can be learned from it. \$\endgroup\$
    – Chris Stratton
    Commented Oct 23, 2020 at 16:02
  • \$\begingroup\$ @ChrisStratton Thank you for your swift reply. Where should i direct my inquiry if its off topic here? Problem with old pcb is that it was programmed to trigger a small relay at a fixed interval. Essentially switching the motor on and off about once every second. I need it to run continuously.. Please see my updated post with new pictures. I imaging i could bypass the relay entirely, but what points to connect where i'm not too sure of.. perhaps this is where your expertise comes in? Again, apologies if this is the wrong forum. \$\endgroup\$
    – hpl002
    Commented Oct 23, 2020 at 16:29
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    \$\begingroup\$ The voltage, voltage, current, frequency and speed (1350 RPM) and capacitor value marked on the motor are typical for single-phase induction motor of the permanent-split-capacitor (PSC) type. The capacitor would be connected at all times, not just for starting. \$\endgroup\$
    – user80875
    Commented Oct 23, 2020 at 16:33
  • \$\begingroup\$ The number of wires coming out of the motor is not consistent with the information marked on the motor. It is possible that two wires are for the thermal protection. The yellow capacitor wire may be connected to the other yellow wire inside the motor. Most motors are not compatible with cycling on and off every second. Has this worked differently during the time that you have owned it? \$\endgroup\$
    – user80875
    Commented Oct 23, 2020 at 17:02
  • \$\begingroup\$ What’s wrong with the PCB? I see a 3 Zener C divider offline regulator and some stuff for full diode bridge maybe current sensing limiting and relay control. what Vcc to Neutral do you get? \$\endgroup\$
    – D.A.S.
    Commented Oct 23, 2020 at 18:46

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As i can no longer "toggle" the switch i simply want the grinder to turn on when the power switch is flicked. Simple as that. Would i be able to jump what i assume is a relay?

You can probably do that. You can probably trace the connections to the PCB and verify that the motor is connected to power when the relay is energized. However it appears to me that the thermal protection mentioned on the motor label is something that is connected to the PCB. If you simply bypass the relay, you will remove that protection.

The protection may be something that can be simply connected in series with the relay. There is a possibility that has failed and the problem with the PCB is that it starts the motor then shuts it off because the failed thermal protection makes it appear that the motor has overheated. You should use an ohmmeter to check the pair of brown wires coming from the motor to a corner of the PCB to determine if it is a closed switch or something else. If it is an open circuit, there it has probably failed. Also try to trace what they are connected to on the PCB.

... the one second interval is way too short ... Could this be signs of a faulty capacitor?

It could be. It could be a sign of something else as I said above. It could also be some other failure on the board.

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