Stepper Motor Question

Will this motor:

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?name=403-1006-NDwork with this driver chip:
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?name=497-2936-5-ND?

Reply to
JonMarkGo
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Very likely, but be sure the stepper doesn't try to draw more current than the L293D wants to provide.

A Google search for 'l293d bipolar stepper' turned up up the following on the first hit. Looks pretty promising:

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-- Gordon

Reply to
Gordon McComb

Just curious....

The spec sheet for the stepper says the 35L048B1B-N is 5V bipolar with 11 ohms resistance per winding which I calculate as 454 ma (5/11) (not counting voltage drop in the driver), and the L293D says good to 600 ma. Is that all you need to do to calculate the current requirement of a stepper when the spec sheet doesn't give a current rating? Or are there other issues to think about?

Reply to
Curt Welch

I didn't bother looking at the spec sheet, but actually, a lot of people "over-volt" steppers to get more torque out of them. That increases the current obviously. But the L293D is stackable (so they say; I've never done it), to increase current rating. Lots of things to play with.

Steppers are seldom *ideal* motors to use unless you use fancier driving techniques, like current chopping. Then you get into all kinds of design parameters for the drivers. So the correct answer to the original question, other than "42," is "maybe."

-- Gordon

Reply to
Gordon McComb

Consider using the SN754410 which is pin compatible with the L293D, but has almost twice the current capacity.

It might be prudent to measure the actual coil resistance of a few of the steppers before totally relying on the spec. sheet. Sometimes, the manufacturer changes the manufacturing process (changes wire gauge) without updating the spec. sheet.

-Wayne

Reply to
Wayne C. Gramlich

IMHO you can't make any sense of a stepper motor spec without a speed against torque graph, stating volts and current. If the supplier doesn't plaster it all over the advert then it's usually fairly safe to assume it's a bit naff. If they give you a 'holding torque' but no 'pull in torque', you know it's a disaster.

So the qualified answer has to be, 'Yes, if your application does not require any kind of speed'.

Steppers come in 2 flavours when you start talking speed. Those with high impedance coils designed for constant volts and those with low impedance coils designed for constant current.

The problem with the constant voltage type is the high impedance of the coil. You can't switch it very quickly so the power falls away like a lead balloon very early on in the speed torque curve.

The constant current type work with LOTS more volts than the coil is rated for. Impedance is overcome by volts so they can go much faster before you reach the lead balloon part of the torque curve. The problem is the extra circuitry required to control the current.

These steppers are by Portescap, but not their fabled disk magnet technology which makes for some of the fastest steppers in creation :o)

Reply to
Robin

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