Switching Power Supply Bracket

[martyscncgarage]

Thanks Marty. I did not know they sell these with this way. I went against my judgment when I ordered the switching supplies. I am going to return them and go toroidal. I may even return the x and y stepper controllers an swap them so they all take A/C. Thanks so much for your thoughts.

If they all take AC then you will need a step down transformer providing the proper AC voltage. (Not the DC power supply I linked to above)

[RJS100]

One quick question. The toroidal transformers do not have an ground (earth ground). Am I correct that you do not connect a ground wire to them?

[Gary Campbell]

True, no ground connection. One of the reasons that few if any torroid systems receive UL or CE certification.

If you're looking for dc voltage regulation, check out www.antekinc.com. They come in most common voltages and have big enough caps to handle a fair amount of regen

[RJS100]

Thanks everyone for all your input. I have dumped the switching power supplies and will be using a large toroidal transformer. I swapped the drives so they all take A/C.

One question: The toroidal transformers to not have an earth ground. Do you simply leave them ungrounded?

Thanks again for all your help... Richard

[martyscncgarage]

What make an model drives do you have?

[martyscncgarage]

Marty... One more question.... The toroidal power supplies are A/C power supplies. My Z-axis driver can be powered by A/C or DC. The X and Y drivers accept DC only. If I use a toroidal transformer, can I add a bridge rectifier to convert from AC to DC for the X and Y axis. Would I need to add some kind of capacitor/inductor filter for the DC supply or is the unfiltered DC supply from the rectifier ok for a stepper driver?

Thanks... Richard

I want to clear something up. Yes, Toroidal Power supplies are AC power supplies BUT they usually have a bridge rectifier and a couple of caps to convert the AC to a DC power supply, that's what I linked.
If my drive took both AC and DC power supplies, I would likely opt for a Toroidal DC power supply. The capacitors can handle any regenerative energy.
You have not described your project/machine.

Marty

[Gary Campbell]

If my drive took both AC and DC power supplies, I would likely opt for a Toroidal DC power supply. The capacitors can handle any regenerative energy.

I am from the other side of the tracks. I would (and most often do) use toroidal as AC transformers, running the drives on AC. Performance is better, due to higher dc volts available to the motors and the AC capable drives have higher ability to resist back emf (regen). For this reason I usually used drives with an amperage range a step or two higher than the motor required.

What this means to a system builder is that he has options. There are plusses and minuses on either side. No method stands out as a clear winner without considering other factors. These factors are the actual use of the machine and its physical properties (weight, rolling resistance, cutting loads, motor inductance, etc.) and the properties of the other components installed into the system.

[martyscncgarage]

If my drive took both AC and DC power supplies, I would likely opt for a Toroidal DC power supply. The capacitors can handle any regenerative energy.

I am from the other side of the tracks. I would (and most often do) use toroidal as AC transformers, running the drives on AC. Performance is better, due to higher dc volts available to the motors and the AC capable drives have higher ability to resist back emf (regen). For this reason I usually used drives with an amperage range a step or two higher than the motor required.

What this means to a system builder is that he has options. There are plusses and minuses on either side. No method stands out as a clear winner without considering other factors. These factors are the actual use of the machine and its physical properties (weight, rolling resistance, cutting loads, motor inductance, etc.) and the properties of the other components installed into the system.

Agreed.
But, like many others, they never take the time to describe and post pictures of their project. More details will get better suggestions.....

[RJS100]

Sorry for the late reply. I am using the Stepper Online CL86Y stepper drivers which can be driven with either 20-80 volts AC or 30-110V DC. I will using their 566 ounce 2 pole Nema 24 closed loop stepper motor running at 35 volts ac for the X and Y axis. I will be using their 1700 ounce Nema 34 closed loop stepper motor running at 70 volts AC for the Z axis. These closed loop steppers will be use for my CNC conversion of a PM-728 milling machine with an added power draw bar.

Since the CL86Y drives are typically used for their Nema 34 motors with a rated current of 6 amps, I programmed the max current for CL86Y to match the current draw for the Nema 24 motors (5 amp).

For what is is worth, I asked the tech support department at Stepper Online if I should power these CL86Y drivers with AC or DC and they said either is fine, but most of their clients use AC.

Thanks... Richard