The Electrical Contractor Network

ECN Electrical Forum
Discussion Forums for Electricians, Inspectors and Related Professionals

Books, Tools and Test Equipment for Electrical and Construction Trades

Register Now!

Register Now!

We want your input!

Featured:
   

2017 NEC and Related
2017 NEC
Now Available!

   
Recent Posts
Locked rotor, no burnout
by geoff in UK
Today at 02:04 PM
Temporarily feeding a panel...
by Potseal
09/29/16 11:05 PM
Massive power outage South Australia
by Meadow
09/29/16 06:46 AM
short circuit??
by Meadow
09/29/16 06:43 AM
Norwegian power?
by Meadow
09/29/16 06:36 AM
New in the Gallery:
12.5A through 0.75mm flex (just out of curiosity)
Shout Box

Top Posters (30 Days)
HotLine1 11
sparky 10
gfretwell 8
Potseal 7
Vlado 6
Who's Online
1 registered (Webmaster), 310 Guests and 4 Spiders online.
Key: Admin, Global Mod, Mod
Page 1 of 2 1 2 >
Topic Options
Rate This Topic
#206292 - 06/14/12 02:32 PM Rotary Phase Converter for elevator
cgw Offline
Member

Registered: 07/29/04
Posts: 133
Loc: Rochester NY
Anyone used a rotary phase converter for a 240/208 3 phase elevator in a building with 240V-1 ph? Any issues I should be aware of?

Top
Work Gear for Electricians and the Trades

Work Gear for Electricians and the Trades
Work Gear for Electricians and the Trades
Arc Flash Clothing, Gloves, KneePads, Tool Belts, Pouches, Tool Carriers, etc. etc....

#206293 - 06/14/12 02:58 PM Re: Rotary Phase Converter for elevator [Re: cgw]
gfretwell Offline

Member

Registered: 07/20/04
Posts: 9012
Loc: Estero,Fl,usa
We used to use a bunch of them in the computer business back when computers filled the room. They went from 208 60hz 3/p to 208 400hz 3/p tho. Same basic machine.
_________________________
Greg Fretwell

Top
#206294 - 06/14/12 03:02 PM Re: Rotary Phase Converter for elevator [Re: cgw]
LarryC Offline
Member

Registered: 07/05/04
Posts: 775
Loc: Winchester, NH, US
New install? If so, why not use a modern VFD. Less maintainance, possibly greater reliability, more flexibility, smaller size, less audible noise, etc.

Top
#206295 - 06/14/12 04:29 PM Re: Rotary Phase Converter for elevator [Re: cgw]
Tesla Offline
Member

Registered: 06/16/04
Posts: 1280
Loc: Sacramento, CA
I've NEVER seen an elevator install/ upgrade which permitted outsiders ( non-elevator technicians ) to touch ANY aspect of their sub-system.

That specifically includes phase conversion/ rectification and transformations.

The latest Otis Elevators are entirely dialed into 480 VAC power. When 208Y120 is Service Power -- they install their own step-up transformer.

The much older Otis Elevator, being replaced, used a rotary rectifier: namely a motor-generator set. It'd spool up before the doors would even open.

Until the modern electronic era, only DC motors were considered suitable for traction effect.

Now, step-wise, these are all being replaced by smart AC motors.

BART hauled its old cars off to the factory to be rebuilt with them.

Likewise the entire railroad fleet is being shunted oven to AC.

I wouldn't even consider using a rotary phase converter for elevator duty.

Perhaps you're looking at / thinking of a motor-generator set.
_________________________
Tesla

Top
#206303 - 06/15/12 07:03 AM Re: Rotary Phase Converter for elevator [Re: gfretwell]
NORCAL Offline
Member

Registered: 09/25/02
Posts: 805
Originally Posted By: gfretwell
We used to use a bunch of them in the computer business back when computers filled the room. They went from 208 60hz 3/p to 208 400hz 3/p tho. Same basic machine.


Your talking about a motor generator, a RPC uses a 3 motor to manufacture a phase from a single phase supply to operate 3 motors on a 1 supply. Most are self starting, some home built models use a "pony motor" to bring them up to speed, & then idle them, (all of them single phase the idler motor).

There are plans out there for folks building their own RPC's, there are a lot of people who never heard of RPC's, here is a link to 1 forum that has plans for them. http://www.practicalmachinist.com/vb/tra...s-plans-101231/

Some people are a bit too "clever" for their own good, but that would be a good topic for a thread on it's own.

Off topic but since a lot of people have never heard of RPC's......

Top
#206306 - 06/15/12 09:06 AM Re: Rotary Phase Converter for elevator [Re: cgw]
gfretwell Offline

Member

Registered: 07/20/04
Posts: 9012
Loc: Estero,Fl,usa
Quote:
Your talking about a motor generator, a RPC uses a 3 motor to manufacture a phase from a single phase supply to operate 3 motors on a 1 supply.


You are right, my bad. We did use a MG
_________________________
Greg Fretwell

Top
#206321 - 06/15/12 11:33 PM Re: Rotary Phase Converter for elevator [Re: gfretwell]
NORCAL Offline
Member

Registered: 09/25/02
Posts: 805
Originally Posted By: gfretwell
Quote:
Your talking about a motor generator, a RPC uses a 3 motor to manufacture a phase from a single phase supply to operate 3 motors on a 1 supply.


You are right, my bad. We did use a MG


At a former employer we had a 100 HP MG set for 400HZ power, it was a PITA to cool the room where the transformer & MG set was, it was later replaced w/ a inverter....

Top
#206326 - 06/16/12 02:26 PM Re: Rotary Phase Converter for elevator [Re: cgw]
gfretwell Offline

Member

Registered: 07/20/04
Posts: 9012
Loc: Estero,Fl,usa
They usually got the 400hz inverter supplies along with the UPS when they went that way.

The MG sets were pretty much trouble free tho.
_________________________
Greg Fretwell

Top
#206335 - 06/17/12 08:45 AM Re: Rotary Phase Converter for elevator [Re: cgw]
cgw Offline
Member

Registered: 07/29/04
Posts: 133
Loc: Rochester NY
Are we still on topic?
An existing building with 240V-1Ph. The new elevator is 208/240V-3ph.
American Rotary and Phase-a-matic are two manufacturers of rotary phase converters.

Someone mentioned a VFD. Can a variable frequency drive be used?

I have yet to meet a elevator manufacturer who would install anything on the line side of their equipment (like a transformer).

Top
#206336 - 06/17/12 10:43 AM Re: Rotary Phase Converter for elevator [Re: cgw]
gfretwell Offline

Member

Registered: 07/20/04
Posts: 9012
Loc: Estero,Fl,usa
Functionally a VFD should work fine. I am not sure if the elevator supplier/inspector is OK with it but I am not sure why they wouldn't like it.
_________________________
Greg Fretwell

Top
Page 1 of 2 1 2 >



ECN Electrical Forums - sponsored by Electrical Contractor Network - Electrical and Code Related Discussion for Electrical Contractors, Electricians, Inspectors, Instructors, Engineers and other related Professionals