Rebuild BM2 green...

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Re: Rebuild BM2 green...

Postby Burgerman » 02 Feb 2016, 22:15

And now the thermostat is inside the case and the fan fitted behind the mounting plate under the seat cover.

810_1272.JPG


So the power module can sit over the hole on 2 8mm spacers so the air can escape underneath in all directions.

810_1278.JPG


And the fan will come on any tie the mosfets reach 45C.
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Re: Rebuild BM2 green...

Postby Burgerman » 02 Feb 2016, 22:43

And the top which will not be seen because there is a flat metal seat plate yet to be fitted:

810_1280.JPG
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Re: Rebuild BM2 green...

Postby expresso » 03 Feb 2016, 01:44

Nice i like that idea - i remember reading about soccer with the chairs and people adding fans to there chairs - but didnt look into that dont remember how they added fans to there chairs -
Quickie P222se - 60Ah ADD ON
Quickie S646se - 150Ah LifePo4
Quickie P220 - Indoor Chair
Bounder Plus - 180Ah LifePo4
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Re: Rebuild BM2 green...

Postby Burgerman » 03 Feb 2016, 02:25

If you program your chair to go. To stop. To turn. When *you* tell it, and you dart about a bit for a few minutes stopping and turning they *all* start shutting down and rolling back the power. And eventually it gets to the point where the chair barely moves.

Mine only does it when I am clearing leaves with a blower for half an hour when darting around and zig zagging. Because I adjusted the temperature in the programming from 55 to 70 centigrade. So it doesn't usually bother me. But now and again in summer it cuts in and pisses me off...

This should help keep it cool. And with the thermostat chip inside the power module, epoxied to an output mosfets, it should be efficient. Its not easy either. Not any wasted space inside that PM! At 45C the fan is on. At 40C it goes off again. So it only wastes power and makes a noise if needed. It is only a small fan too, but its circulation is quite good because of the way its working and the way the PM is spaced off the surface. The cool airflow around it and from behind it is pretty good.
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Re: Rebuild BM2 green...

Postby Burgerman » 03 Feb 2016, 02:37

There will be a 3 position lighting switch on there too. OFF/AUTO/ON. So I can leave it on auto normally, and a light sensor will decide. And a movement sensor.

So on auto: if moving + dark light comes on. If it stops moving or gets light, they go off after say 2 or 5 mins.
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Re: Rebuild BM2 green...

Postby Burgerman » 03 Feb 2016, 02:46

I presume you haven't looked inside your power module yet then?

Image
Image :lol:

Nothing to be scared of. You just get to see how crappy the build quality is, wit only a rubber foam pad making the pressure for all the connections to the power mosfets. Amazing they don't fail more often. And that they are using just 8 power mosfets. Unlike the Roboteq with 32... No wonder they get hot really is it.
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Re: Rebuild BM2 green...

Postby shirley_hkg » 03 Feb 2016, 05:36

O M G !

WHAT a confidence they have.
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Re: Rebuild BM2 green...

Postby Burgerman » 03 Feb 2016, 11:17

Well surprisingly it does appear to work pretty well! I and the rest of us using all of PG Drives systems, inc Rnet should take the thing apart and use a scotch bright cloth or fine glass paper to clean those contact point every year or so though. It will likely prevent failure.
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