Re: [CAD_CAM_EDM_DRO] Re: Specs on Sigma Stepper for Series I Bridgeport?

Hi Mike,

I experimented with the Sigma motors on my Bridgeport and found the best
overall performance was by just using 2 coils:
2 connected to phase A+
8 connected to phase A-
1 connected to phase B+
6 connected to phase B-
The other terminals are left unconnected.

With Geckos set to full current and with a 75V supply I get reliable
2.4m/min (96IPM) rapids and plenty of torque.

My power supply is based on the original 110V transformer. If the
transformer is rewired to twice it's supply voltage (in my case 460V on
a 230V supply) then the output will be 55V. When rectified and smoothed
the result is 75VDC. The rectifier and smoothing caps are rescued from
the control cabinet.

Les

>>
>>For the Sigma motors:
>>(identified by 8 terminals in pairs with a plastic partition
>>between the terminals of each pair)
>>
>>To connect the phase windings in series and set the controller to max
>>amps ( GECKO wiring recommended for orig BP type steppers*********)
>>terminals:
>>6 jumpered to 5
>>3 connected to phase A+
>>1 connected to phase A-
>>
>>8 jumpered to 7
>>4 connected to phase B+
>>2 connected to phase B-
>>
>>
>>