Is my power supply up to the job ?

[DJ Morrow]

I have a couple of International Power Supply IH28-6 power supplies that I bought cheap a while back. They're rates at 28V / 6Amps.

I'm using Gecko G201's which require between 24 and 80 volts. The Gecko installation notes say that max. power supply current required is 67% of the motor's rated phase current.

My 3 steppers are made by MCG and are rate as:
Bipolar Parallel - 2.31 Volts / 4.20 amps
or
Bipolar Series - 4.70 Volts / 2.14 amps.

Is this power supply up to the job for use on my little Sherline mill ?

Should I run in parallel or series with this power supply ?

[ViperTX]

I would use both power supplies and configure the steppers for bipolar parallel operation.

[CJL5585]

Originally Posted by DJ Morrow Should I run in parallel or series with this power supply ?

The power supplies should be wired in parallel. You should also add a large filter capacitor, although the supplies are regulated supplies. The filter capacitor(s) are used to absorb energy when the steppers are slowing down, and to furnish peak current when the steppers begin to move.

Jerry

[DJ Morrow]

Originally Posted by CJL5585 The power supplies should be wired in parallel. You should also add a large filter capacitor, although the supplies are regulated supplies. The filter capacitor(s) are used to absorb energy when the steppers are slowing down, and to furnish peak current when the steppers begin to move. Jerry

Can you give me an idea of how large ?

[ViperTX]

Rather then messing with paralleling the power supplies, I would run the X and Z axis from one power supply and the Y axis from the 2nd power supply.

Another option is to have the Z-axis wired for bipolar-serial and using the scheme in the previous sentence.

[CJL5585]

Originally Posted by DJ Morrow Can you give me an idea of how large ?

A good value would be 10,000 uF rated at 35 Volts DC.

The reason I suggested wiring the power supplies in Parallel is this:

I have used the same supplies that you have 28 VDC and 6 Amps. My experience was that the supplies would deliver a consistant 4.6 Amps without running at an excessive temperature on the chassis and heatsink. Above that, a lot of the energy is dissipated as heat.

My personal thought is that ONE supply will not fully furnish the current required for 2 stepper motors, although 1 might be wired in parallel and 1 in series.

However, the supplies connected in parallel will provide the necessary voltage and current for the steppers.

I would also suggest that the X and Y axis be wired Parallel and the Z axis be wired Series (Unless you are going to have a spindle or router that weighs 6 pounds).

Jerry