Underwater scooter pcb removal and replaced with magnetic switch

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I have underwater scooters with a pcb which are often faulty.
I wanted to replace the pcb with a magnetic switch.
The pcb has 2 reed switches activated by outside magnet triggers.
The pcb has leakage sensors but otherwise doesn’t seem necessary
The unit is 12 volt ,300 watt motor with rechargeable battery.

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Hi Phil,

Could you send through a photo of your PCB? From that, we might be able to guess its capabilities, and whether you’d be able to perform a successful PCB-ectomy

-James

1 Like
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I cant see how to send photos

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Hi Phil,

Apologies, since you’re a new user attachments aren’t available, but I’ve fixed that so it should work now. Drag and drop or copy and paste should work.

Let me know if it doesn’t
-James

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[quote=“Phil198349, post:1, topic:13688, full:true”]
I have underwater scooters with a pcb which are often faulty.
I wanted to replace the pcb with a magnetic switch.
The pcb has 2 reed switches activated by outside magnet triggers.
The pcb has leakage sensors but otherwise doesn’t seem necessary
The unit is 12 volt ,300 watt motor with rechargeable b*

IMG7332042119670275502
IMG7332042119670275502360×740 117 KB

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strong text

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20220407_152824
20220407_1528241920×2560 243 KB

20220407_152816
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Hi Phil,

While that board seems far too complex to replace with standalone components, what it could definitely do with is some conformal coating to protect against corrosion. MG Chemicals have a good range of coatings, and we stock some of them:

-James

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Hi Phil, James.
Looks like this board has had a water problem already…Conformal coating might be a bit late for this one, but you never know, a good clean up and it may still work. I would give any other boards the once over while you have got it apart. Also replace those steel (looks like steel, they are rusty) screws and probably washers with quality stainless , 316 at minimum, NOT 304. Oh and fix up where the water got in too, might help in the future.

James is correct. You will not be able to replace that with a couple of magnetic switches. It looks like it does more than switch something and lacking detailed information a replacement is really the only way out.
Cheers Bob

1 Like
11

Thanks for the reply. The photo was a damaged corroded pcb
I have 20 of these scooters. I dont understand pcb’s .
This one has two sensors. One for leakage , one for a heat sensor on the motor.
Can you tell me the reason why such a complex pcb is needed…
The units leak from new but i have fixed that issue after dismantling them so the sensors are not necessary in my thinking.

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Hi Phil.
I would guess that that board has been subject to moisture for some time but not being an industrial chemist I could not put a time on it.

Not knowing anything about what it is going into I have no idea at all. For commercial reasons I am sure the manufacturer would not have made it complex if they didn’t need to.

Although the writing on the board looks like Chinese or Japanese, on the first photo the text language and “Rp721.000” suggest Indonesia. So at about 10,750 Rp to the dollar that is not too expensive.
Cheers Bob

1 Like
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Thanks