I am currently working on a project which requires 5 stepper motors, in this case I am using Nema 17, to run on an Arduino. To accomplish this I have bought A4988 drivers and a Sensor Shield.
I am unsure how to wire the power input. This picture suggests that I wire it straight in series, but that it needs to be 8V minimum?
4 wire connection bi-polar or 6 connection wire uni-polar
How would I go about wiring this so that all 5 stepper motors/drivers get power from this supply? Is this battery 'strong' enough to power all 5 simultaneously?
I am asking because last time I tried using this battery to power a cheap stepper motor/driver combo it got really hot and ended up burning out the UNO when I just plugged the battery into the AC port (note: I had the usb connected at the same time, not sure if that change anything)
INTP:
I think you'd be better off with two lithiums instead of NiMHs. And that battery is 3.3 Ah, not 3.3 A. Big difference.
So the battery is able to supply 3.3 A for 1 hour? Do you think this is enough for 3 stepper motors?
What sort of batteries do you have in mind when you mentioned lithium? Do you think I would be better off using a power supply?
First you need to tell us which motors you are talking about, rather than listing a subset of
their properties (including a meaningless voltage value, and no current or resistance rating).
Stepper motors are current driven. Stepper drivers need substantially higher supply voltage
than the product of motor current and resistance. Typically 5 to 20 times more.
7.2V is not going to be adequate as 8V is the absolute minimum for the A4988 to function.
Normally people use 24V for stepper systems, or higher for high speed. 12V may be viable,
but you need to tell us the exact motors involved.
If the motors are high current then DRV8825's will be better than A4988's, and if very high
current you'll need active cooling for the drivers.
[ The battery you link to has no useful data listed, such as max current or discharge and charge
curves, just a lot of marketing puff saying its great. All adjectives and no numbers should ring alarm
bells. ]
MarkT:
First you need to tell us which motors you are talking about, rather than listing a subset of
their properties (including a meaningless voltage value, and no current or resistance rating).
Stepper motors are current driven. Stepper drivers need substantially higher supply voltage
than the product of motor current and resistance. Typically 5 to 20 times more.
7.2V is not going to be adequate as 8V is the absolute minimum for the A4988 to function.
Normally people use 24V for stepper systems, or higher for high speed. 12V may be viable,
but you need to tell us the exact motors involved.
If the motors are high current then DRV8825's will be better than A4988's, and if very high
current you'll need active cooling for the drivers.
[ The battery you link to has no useful data listed, such as max current or discharge and charge
curves, just a lot of marketing puff saying its great. All adjectives and no numbers should ring alarm
bells. ]
I found this for the stepper motor I am using:
Current/phase RMS: 3.0a Voltage 1.74VDC Resistance/phase: 0.58ohms inductance phase 1.28@ 1000 Hz NEMA 17
Is a power supply that gives 12V 30A enough to power 5 of these?
nyxraia:
Is a power supply that gives 12V 30A enough to power 5 of these?
That depends. Measure the current draw of a single stepper motor using a multimeter or a dc clamp meter while powering it with 12V source and post it here.
3A is beyond any single-chip driver - you'll need Gecko drives or similar cheap industrial stepper controllers.
Why choose those motors when most NEMA17's can be driven cheaply and easily - 1A to 1.5A NEMA17's
are much simpler to manage.
