wrong heatsink in parts list?

owad

wrong heatsink in parts list?
October 03, 2007 12:38PM

Registered: 17 years ago
Posts: 40

I think the heatsink in the parts generator is wrong. Mouser part #532-566010B03400G is a "Vertical mount, slide-on with tabs" heatsink. It's rated for 11.5

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ZachHoeken

Re: wrong heatsink in parts list?
October 03, 2007 03:08PM

Admin
Registered: 17 years ago
Posts: 1,487

what part was this specified for?

we have two types of heatsinks in the BOM: big and small. that one is the 'big' one which is intended to be mounted on the L298N. the 'small' one is this: [www.mouser.com] and is intended to be mounted on the TIP110's.

just looking for a bit more info...

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owad

Re: wrong heatsink in parts list?
October 03, 2007 04:09PM

Registered: 17 years ago
Posts: 40

In the part list it's called the "big heat sink". That page links to Mouser part #532-566010B03400G. . If you download page 1702 of the mouser catalog, you'll see it in Figure W. The heat sink is designed to snap in rather than be screwed on, and doesn't match any part that I can find.

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ZachHoeken

Re: wrong heatsink in parts list?
October 03, 2007 05:21PM

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Registered: 17 years ago
Posts: 1,487

ah, i see. i'll change the big heatsink part to be this new part you've found. thanks!

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ZachHoeken

Re: wrong heatsink in parts list?
October 03, 2007 05:30PM

Admin
Registered: 17 years ago
Posts: 1,487

i do think we might need a bit bigger one. i'm not really too knowledgable about the heatsink requirements, but that one is designed for a TO-220 housing, whereas the L298 is a MULTIWATT-15 housing. i also think it puts out more heat than the TIP120's, so we might want to beef it up a bit.

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nophead

Re: wrong heatsink in parts list?
October 03, 2007 06:42PM

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Registered: 17 years ago
Posts: 7,879

Use MOSFETS and ditch the heatsinks!

[www.hydraraptor.blogspot.com]

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owad

Re: wrong heatsink in parts list?
October 03, 2007 08:57PM

Registered: 17 years ago
Posts: 40

owad Wrote:
-------------------------------------------------------
> I think the heatsink in the parts generator is
> wrong. Mouser part #532-566010B03400G is a
> "Vertical mount, slide-on with tabs" heatsink.
> It's rated for 11.5

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owad

Re: wrong heatsink in parts list?
October 03, 2007 09:22PM

Registered: 17 years ago
Posts: 40

How about the 532-7023B-MTG?

Channel style w/folded back fins, TO-220, Multiwatt
Vertical
Black anodized
Solder Tabs
4.4

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Anonymous User

Re: wrong heatsink in parts list?
October 03, 2007 10:04PM

owad Wrote:
-------------------------------------------------------
> > It's rated for 11.5

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owad

Re: wrong heatsink in parts list?
October 04, 2007 11:27AM

Registered: 17 years ago
Posts: 40

The SureStep motors are rated at 2.8 A/phase.

I'm curious to hear any opinions of the 532-7023B-MTG, as I'd like to order some shortly, and I'm not at all certain if it's appropriate.

As for the solder tabs, they're in a little pile of dust beside my grinder.

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Anonymous User

Re: wrong heatsink in parts list?
October 04, 2007 11:46AM

The L298 is only rated for 2A per phase. It *might* be able to take 2.8A if you were stepping fast, but you'd have to cut the power back as soon as you stopped stepping. The stock firmware doesn't do anything like this, so if you're using that, you'll need to run it at <2A all the time (either by lowering the torque setting or adding resistors)

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owad

Re: wrong heatsink in parts list?
October 11, 2007 12:40PM

Registered: 17 years ago
Posts: 40

I have a surestep running at 70% torque with the 532-7023B-MTG heatsinks and it seems to be holding up pretty well (Z axis).

The heatsink is very close to touching the diodes, though.

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