Need Help!- Rotary Phase converter and router connection

[MaNo]

The electrician to install a rotary phase converter from http://www.deselectric.com/ and connect my 3-phase CNC router had to go overseas for medical reasons and I have been stuck for a few months now......

I had several other electricians over to see what's required and most, if not all, have never seen a rotary phase converter and each one comes up with different opinions, advise and/or plans. I am getting extremely frustrated and would appreciate advice from qualified people on this forum.

This link shows a diagram illustrating my blurb below. It's not professional but helps in clarifying things. http://dl.getdropbox.com/u/2043845/CNC%20wiring.jpg

What I have at present:

a) Electricity as supplied by power company is 220V, single phase.

b) Meter panel has now 50 Amp breaker.

c) # 6 AWG from meter panel to breaker panel. Distance about 60 feet.

d) Main breaker on breaker panel 50 Amps

e) # 8 AWG with 30 Amp breaker from breaker panel to location of CNC machines Distance about 110 feet.


Other equipment,SINGLE phase, on same breaker panel but on *separate* breakers and wires, running at the same time.

f) 220V 2.2 KW dust collector

g) A/C unit, 12000 BTU.

h) 3 desk top computers

i) about 2 Kw for lighting and miscellaneous


What I need installation/modification for:

1) 20 HP rotary phase converter to supply 3-phase to the following equipment...

2) 5KW spindle,

3) 4KW vacuum pump

4) 4KW compressor (the compressor shipped is 380V rated ??? Amps but factory has sent a step-up transformer. I don't know what this means as far as wattage is concerned)

5) small pump for water cooled spindle

Factory suggested 18KW total for items 2 (with its controller), 3, 4 and 5 running together.


Sequence I am going to use for switching on equipment:
- Rotary phase converter, compressor, coolant pump, spindle (warming up), vacuum pump (if/when needed)



I realize that some changes are necessary,but what ?

- breaker (item b) to what Amperage?

- is # 6 AWG ,(item c) good enough? ( I say 'good enough' because I may move to different location in near furture so I wish to limit my expenses where possible)

- main breaker (item d) ??? Amps

- is the #8 AWG (item e) good enough? (same 'good enough' reason as for #6 AWG)

if you want me to post additional details, you can also email nmajerus AT caribsurf DOT com

Your help and/or advise is much appreciated.

Thanks

[Ark1]

20 KW will require about 81 AMPs and you only have a 50 Amp Main breaker.

A 100 AMP 220Volt service is marginal as you will not be able to run much else. It is the air conditioner load that will trip the 100 amp service with the roto phase running the CNC machine.

In an ideal situation a 200 amp service is the way to go for a small shop @ 220volts.

As for the conductor size and distance voltage drop will start to become a problem over 150 feet without increasing to the next bigger size conductor. Since you will not be starting the machine under load you should be able to get by on rated size conductors for the current being transmitted on the distances stated.

TonyK.

[TOTALLYRC]

Originally Posted by MaNo The electrician to install a rotary phase converter from http://www.deselectric.com/ and connect my 3-phase CNC router had to go overseas for medical reasons and I have been stuck for a few months now...... I had several other electricians over to see what's required and most, if not all, have never seen a rotary phase converter and each one comes up with different opinions, advise and/or plans. I am getting extremely frustrated and would appreciate advice from qualified people on this forum. This link shows a diagram illustrating my blurb below. It's not professional but helps in clarifying things. http://dl.getdropbox.com/u/2043845/CNC%20wiring.jpg What I have at present: a) Electricity as supplied by power company is 220V, single phase. b) Meter panel has now 50 Amp breaker. c) # 6 AWG from meter panel to breaker panel. Distance about 60 feet. d) Main breaker on breaker panel 50 Amps e) # 8 AWG with 30 Amp breaker from breaker panel to location of CNC machines Distance about 110 feet. Other equipment,SINGLE phase, on same breaker panel but on *separate* breakers and wires, running at the same time. f) 220V 2.2 KW dust collector g) A/C unit, 12000 BTU. h) 3 desk top computers i) about 2 Kw for lighting and miscellaneous What I need installation/modification for: 1) 20 HP rotary phase converter to supply 3-phase to the following equipment... 2) 5KW spindle, 3) 4KW vacuum pump 4) 4KW compressor (the compressor shipped is 380V rated ??? Amps but factory has sent a step-up transformer. I don't know what this means as far as wattage is concerned) 5) small pump for water cooled spindle Factory suggested 18KW total for items 2 (with its controller), 3, 4 and 5 running together. Sequence I am going to use for switching on equipment: - Rotary phase converter, compressor, coolant pump, spindle (warming up), vacuum pump (if/when needed) I realize that some changes are necessary,but what ? - breaker (item b) to what Amperage? - is # 6 AWG ,(item c) good enough? ( I say 'good enough' because I may move to different location in near furture so I wish to limit my expenses where possible) - main breaker (item d) ??? Amps - is the #8 AWG (item e) good enough? (same 'good enough' reason as for #6 AWG) if you want me to post additional details, you can also email nmajerus AT caribsurf DOT com Your help and/or advise is much appreciated. Thanks

You need a good electrician no doubt.
It looks like you will have to start from scratch as you incoming power is well below what you need to run the CNC stuff, not to mention the rest of the stuff you have listed.
As far as the wire size, there are online calculators for how many amps will each size wire carry and how far it will carry it.
On your sequence of startup, I would start the compressor later in the sequence as the rest of the motors will make the "wild" leg more stable. The wild leg is the part of the 3 phase that is being generated by the RPC.
A 200 amp service will give you plenty of extra capacity when you add something else in the future.

Mike

[MaNo]

Tony and Mike, Thank you very much for your information.

Mike, I am unfortunately not ready to start from scratch although that would probably be the best solution. Reason being that I am looking for an other place, hence I do not wish to spend thousands of dollars rewiring this place. I' ll move as soon as a I find a new, suitable location. Finding an other place might take a good few months though and I would like the equipment to to earn some money in the meantime. If need be, I will switch off the A/C while machine is running although it won't make life very pleasant...

Starting the compressor later in the sequence on a more stabilized the 3rd leg does not represent a problem. Compressed air is only needed to lift the dust skirt and when doing an automatic tool change.

Tony, if I read you correctly, my wire gauges are borderline and the breakers are too small. By changing breakers I might limp along. Am I right?

By the way, I had the A/C unit listed under the same 'branch' as the other 110V stuff but I am sure you all understood that it is 220V. It's on a separate wire with a 20 Amp breaker and the sticker on it says: RATED COOLING INPUT 1.23KW - MAX INPUT CURRENT: 9.6 AMP.

Essentially all other 110 V breakers are for lights and plugs which, with the exception of the 3 computers and 1 KW of fluorescent lighting are used only rarely and I can make sure they are not used while the RPC is running.

I realize it is only a make-do set up but if I am not endangering other tenants in this warehouse complex would you go ahead with the higher rated breakers if you were in my shoes?

Thanks for your time and opinion(s)

[TOTALLYRC]

Increasing the breaker size could well lead to a FIRE if the wires are too small.
Be very careful.

Mike

[MaNo]

Hi Mike,

Thanks for warning. I am aware of the fire risk and wouldn't change the breaker(s) without consulting with electrician, still, I want to thank you for taking the time to point it out. A reminder is never a waste.

As I said in previous post, RPC and CNC installations are not well known here and I want to be able to intelligently analyze a proposal from an electrician.

The thing is that the guy (who is in the hospital in the States) was sure I could operate the machines with some relatively minor modifications he would need to do to my present setup (not to the machines). Although he did say that it is borderline and no room for expansion. Unfortunately his secretary has no idea where his papers are.

Thanks again,
Norbert

[Ark1]

You need a 100 AMP 220 Volt service to run this roto phase converter and the mill in this building. The service you now have is too small.

Everything is under sized. You just cannot increase the breaker size without increasing the wire size. Currently what you have is too small for this installation.

The only other option is to rent( Or buy) a generator and feed the mill directly. Then when you move you can find or upgrade the new building to suit your needs and future expansion and return or sell the generator.

Possibly you can find a farm tractor with a PTO mounted Generator for the time being.

Sorry about the bad news, but I am an electrician and know you can't get what you want with what you have.

TonyK.

[MaNo]

Belated THANKS, guys...

Installing new wires and breakers...