New Machine Build- power supply

[bbrreid]

larry,
did this one get through to you ? and can any one else throw in an opinion
all welcome.

Requiring some assistance and hoping you can help. I am installing your boards in a lathe for a company called Reid Engineering in Dundee, Scotland. A couple of problems I have with your recommended supply layout.
1 : You show a main transformer with an input of 120Vac which I would need to change to 415Vac, as this is the 3phase voltage in Scotland, you do not show a Kva of transformer is there a set size or how have you worked out you loading I would assume that the output will be 180Vac
2 : You have a 40Ov 25 amp Bridge Rectifier with a 25000micro farad capicitor across it showing 2 motor power outlets. I would take it that a 400v 35 amp rectifier would do however the capacitor is a problem I am assuming that it is supposed to be a 400Vdc 25000micro farad however I cannot seem to find that size. I can find 10 and 15 thousand would these do.
3 : You show on your drawing that the main transformer has two motor power outlets I would then assume from this that you can run 2 boards from one transformer however you only show one outlet on the control side.
4 : You do not show a size of capacitor for the control power side. Although would a 240Vac/1 12Vdc power supply unit do the same and bypass the need for an isolated transformer, with rectifier and capacitor

Hopefully you understand my problems and are able to give me some answers

[Larken]

The drawing in the manual is just a recommendation. Depending on the motors and the voltage, you will have design your own and adjust accordingly.

How big are the motors ? The max power your supply need to be is 160 vdc @ 20-25 amps per motor (because thats the max the viper 200 can run anyway).
Sometime you can getaway with a smaller current rating since the average current is usually much less than the full load current.

You can use separate power suppys for each motor or run 1 big one.

Your transformer (120v, 220 or 415v primary) should have a secondary output voltage of about 100-115 volts AC. Multiply the AC * 1.414 to get the DC voltage.

The Main capacitor should be 200 volts at 10000 uF or higher.
The rectifier(s) need to be rated at your maximum current.


On the control side (12 volt), since the DB 9 connector is grounded (or can be grounded to a chassis when mounted) you can use just one 12 volt supply, 1 amp is plenty. Its a good idea to ground the control side powersupply , but have the highpower powersupply float( not grounded).