Im just about done building the 10hp RPC. Having run it...I find that
one leg is 240 volts, one is 215 and one is 205, unloaded.

What values run caps will I need? If I get it correctly..its 15mf per
hp, so that would make each of them 150mf?

I would assume that 370 VAC or higher voltage rating is what I want,
given start up surges and what not?

Do I find 2 big caps, or a bunch of little ones?

Some advice would be appreciated

Gunner

"Pax Americana is a philosophy. Hardly an empire.
Making sure other people play nice and dont kill each other (and us)
off in job lots is hardly empire building, particularly when you give
them self determination under "play nice" rules.

Think of it as having your older brother knock the **** out of you
for torturing the cat." Gunner

In article , Gunner Asch says...

Do I find 2 big caps, or a bunch of little ones?

Capacitors values add when they're put in parallel. Just
be sure they all have an acceptably high voltage rating, the
370 I think is a good number. But you can make the total mfd value
up by paralleling whatever ones you can find.

Jim


--
==================================================
please reply to:
JRR(zero) at pkmfgvm4 (dot) vnet (dot) ibm (dot) com
==================================================

Gunner
I still have the write-ups that Fitch did on how to balance a RPC. I can
forward them to you if you give me a good address to send them to that will
not bounce them. does gunner at ligtspeed net work ?
lg
no neat sig line

"Gunner Asch" wrote in message
...
Im just about done building the 10hp RPC. Having run it...I find that
one leg is 240 volts, one is 215 and one is 205, unloaded.

What values run caps will I need? If I get it correctly..its 15mf per
hp, so that would make each of them 150mf?

I would assume that 370 VAC or higher voltage rating is what I want,
given start up surges and what not?

Do I find 2 big caps, or a bunch of little ones?

Some advice would be appreciated

Gunner

"Pax Americana is a philosophy. Hardly an empire.
Making sure other people play nice and dont kill each other (and us)
off in job lots is hardly empire building, particularly when you give
them self determination under "play nice" rules.

Think of it as having your older brother knock the **** out of you
for torturing the cat." Gunner

On Tue, 18 Oct 2005 07:20:57 -0700, "larry g"
wrote:

Gunner
I still have the write-ups that Fitch did on how to balance a RPC. I can
forward them to you if you give me a good address to send them to that will
not bounce them. does gunner at ligtspeed net work ?
lg
no neat sig line

Ayup..please do do. and yes..thats a good one. Thanks!

Gunner


"Gunner Asch" wrote in message
.. .
Im just about done building the 10hp RPC. Having run it...I find that
one leg is 240 volts, one is 215 and one is 205, unloaded.

What values run caps will I need? If I get it correctly..its 15mf per
hp, so that would make each of them 150mf?

I would assume that 370 VAC or higher voltage rating is what I want,
given start up surges and what not?

Do I find 2 big caps, or a bunch of little ones?

Some advice would be appreciated

Gunner

"Pax Americana is a philosophy. Hardly an empire.
Making sure other people play nice and dont kill each other (and us)
off in job lots is hardly empire building, particularly when you give
them self determination under "play nice" rules.

Think of it as having your older brother knock the **** out of you
for torturing the cat." Gunner


"Pax Americana is a philosophy. Hardly an empire.
Making sure other people play nice and dont kill each other (and us)
off in job lots is hardly empire building, particularly when you give
them self determination under "play nice" rules.

Think of it as having your older brother knock the **** out of you
for torturing the cat." Gunner

On Tue, 18 Oct 2005 07:20:57 -0700, "larry g"
wrote:

Gunner
I still have the write-ups that Fitch did on how to balance a RPC. I can
forward them to you if you give me a good address to send them to that will
not bounce them. does gunner at ligtspeed net work ?
lg
no neat sig line

There was an excellent paper written by a guy named Jim Hanrihan or
something close to that -- but I can't find it now. I think it was
in the dropbox, at least at one time.

Bob Swinney might still have it. I'll ping Fitch too.

On Tue, 18 Oct 2005 17:47:33 GMT, Ignoramus6433
wrote:

Jim Hanrahan wrote an excellent article on building phase converters.

http://www.metalwebnews.com/howto/ph-conv/ph-conv.html

I followed it when I made my own converter. It works fine and server
me about every other day.

i

On Tue, 18 Oct 2005 12:41:00 -0500, Don Foreman wrote:
On Tue, 18 Oct 2005 07:20:57 -0700, "larry g"
wrote:

Gunner
I still have the write-ups that Fitch did on how to balance a RPC. I can
forward them to you if you give me a good address to send them to that will
not bounce them. does gunner at ligtspeed net work ?
lg
no neat sig line

There was an excellent paper written by a guy named Jim Hanrihan or
something close to that -- but I can't find it now. I think it was
in the dropbox, at least at one time.

Bob Swinney might still have it. I'll ping Fitch too.



Mine is pony motor started, all I need are some suggestions for values
of run caps to balance it out. So far..all I can determine is that
15mf per hp is sometimes suggested..which would make my needs about
150 mf

Im still not happy about using a 3450 rpm screamer as a idler..but
thats all I have handy..so I got to " run what I brung"

Ive got about a dozen run caps..but they are only 6 and 17 mf...so I
need to scrounge up some bigger valued ones and Ive not found any in a
couple weeks or so of haphazardly looking for Stuff.

Gunner


"Pax Americana is a philosophy. Hardly an empire.
Making sure other people play nice and dont kill each other (and us)
off in job lots is hardly empire building, particularly when you give
them self determination under "play nice" rules.

Think of it as having your older brother knock the **** out of you
for torturing the cat." Gunner

That's it! Thanks, Ig! I mispelled the name.

On Tue, 18 Oct 2005 17:47:33 GMT, Ignoramus6433
wrote:

Jim Hanrahan wrote an excellent article on building phase converters.

http://www.metalwebnews.com/howto/ph-conv/ph-conv.html

I followed it when I made my own converter. It works fine and server
me about every other day.

i

On Tue, 18 Oct 2005 12:41:00 -0500, Don Foreman wrote:
On Tue, 18 Oct 2005 07:20:57 -0700, "larry g"
wrote:

Gunner
I still have the write-ups that Fitch did on how to balance a RPC. I can
forward them to you if you give me a good address to send them to that will
not bounce them. does gunner at ligtspeed net work ?
lg
no neat sig line

There was an excellent paper written by a guy named Jim Hanrihan or
something close to that -- but I can't find it now. I think it was
in the dropbox, at least at one time.

Bob Swinney might still have it. I'll ping Fitch too.

On Tue, 18 Oct 2005 18:25:59 GMT, Gunner Asch
wrote:




Mine is pony motor started, all I need are some suggestions for values
of run caps to balance it out. So far..all I can determine is that
15mf per hp is sometimes suggested..which would make my needs about
150 mf


Hanrahan discusses run caps in some detail. But the guidelines are
just a starting point. You still need to "balance" your RPC by
experiment, running the load for which you want it balanced because
it'll only be balanced for that load. A bigger idler requires less
balancing and is more tolerant of variations in load. But, like ya
say, ya run whut ya brung.

On Tue, 18 Oct 2005 18:25:59 GMT, Gunner Asch
wrote:
BIG BIG SNIP

Ive got about a dozen run caps..but they are only 6 and 17 mf...so I
need to scrounge up some bigger valued ones and Ive not found any in a
couple weeks or so of haphazardly looking for Stuff.

Gunner
XXXXXXXXXXXXXXXXXXXXXXXXXXX

Hey Gunner,

Try Apex in Sun City...whoops....Sun Valley. I was out there at Xmas,
and I picked up four non-PCB 40mf @ 330VAC. 10 bucks each, which
seemed kinda stiff until I looked at the prices I'd have to pay around
here, IF they were even easily available!!

I already have/had my RPC running since last year, and balanced to a
point using a bunch of little ones (5, 10, 15, 20) that I already had
"in stock" here from old elevators. I'm not happy with the voltage
variations leg-to-leg though, but even so I haven'f needed to "do"
anything yet that mattered (like a really good surface grind), so I
have not installed these new ones yet. But I will. Lemme know how
you make out with what do.

You probably already know this, but it is:


APEX Electronics, 8909 San Fernando Rd.,

Sun Valley, CA, 91352

Tel: (818) 767-7202

Fax: (818) 767-1341

Web: http://www.apexelectronic.com

Email:

Take care.

Brian Lawson,
Bothwell, Ontario.

"Brian Lawson" wrote:
Try Apex in Sun City...whoops....Sun Valley. I was out there at Xmas,
and I picked up four non-PCB 40mf @ 330VAC. 10 bucks each, which
seemed kinda stiff until I looked at the prices I'd have to pay around
here, IF they were even easily available!!

Best place I've found for run caps is USA Manufacturing. Here is their
latest ad circular; run caps are towards the end:
http://www.usamfg.net/EMAILIMAGES/CATALOG.pdf

Jon

On Wed, 19 Oct 2005 01:03:58 GMT, Ignoramus6433
wrote:

On Tue, 18 Oct 2005 20:01:08 -0400, Brian Lawson wrote:
Try Apex in Sun City...whoops....Sun Valley. I was out there at Xmas,
and I picked up four non-PCB 40mf @ 330VAC. 10 bucks each, which
seemed kinda stiff until I looked at the prices I'd have to pay around
here, IF they were even easily available!!

I got five 92 uF, 535 VAC oil filled caps for a dollar each. Each was
the size of a vodka bottle.

Used two in my RPC.

i

Hey Iggy,

Where???? I mean where did you get them.
And I guess, where did you put them too?!?! What "size" is the RPC?

Take care.

Brian Lawson,
Bothwell, Ontario.

On Tue, 18 Oct 2005 20:01:08 -0400, Brian Lawson
wrote:

On Tue, 18 Oct 2005 18:25:59 GMT, Gunner Asch
wrote:
BIG BIG SNIP

Ive got about a dozen run caps..but they are only 6 and 17 mf...so I
need to scrounge up some bigger valued ones and Ive not found any in a
couple weeks or so of haphazardly looking for Stuff.

Gunner
XXXXXXXXXXXXXXXXXXXXXXXXXXX

Hey Gunner,

Try Apex in Sun City...whoops....Sun Valley. I was out there at Xmas,
and I picked up four non-PCB 40mf @ 330VAC. 10 bucks each, which
seemed kinda stiff until I looked at the prices I'd have to pay around
here, IF they were even easily available!!

I already have/had my RPC running since last year, and balanced to a
point using a bunch of little ones (5, 10, 15, 20) that I already had
"in stock" here from old elevators. I'm not happy with the voltage
variations leg-to-leg though, but even so I haven'f needed to "do"
anything yet that mattered (like a really good surface grind), so I
have not installed these new ones yet. But I will. Lemme know how
you make out with what do.

You probably already know this, but it is:


APEX Electronics, 8909 San Fernando Rd.,

Sun Valley, CA, 91352

Tel: (818) 767-7202

Fax: (818) 767-1341

Web: http://www.apexelectronic.com

Email:

Take care.

Brian Lawson,
Bothwell, Ontario.



Ayup...Ive been there before...but the City of Sun Valley has me on
the Banned list.
Im only allowed in there if accompanied by keepers, or by having a
long cable shackled to my leg and payed out via winch.

I guess having to send in the Search and Rescue teams..(3
actually..the first two got side tracked for a week or two after
someone suggested that they build a mobile command post from parts on
hand..and when they were found..the vehicle was about the size of a
pocket battleship) to find me again. Though Pizza Hut used the air
drops on the strobe for publicity purposes and were quite happy......

Gunner

"Pax Americana is a philosophy. Hardly an empire.
Making sure other people play nice and dont kill each other (and us)
off in job lots is hardly empire building, particularly when you give
them self determination under "play nice" rules.

Think of it as having your older brother knock the **** out of you
for torturing the cat." Gunner

On Tue, 18 Oct 2005 14:34:46 -0500, Don Foreman
wrote:

On Tue, 18 Oct 2005 18:25:59 GMT, Gunner Asch
wrote:




Mine is pony motor started, all I need are some suggestions for values
of run caps to balance it out. So far..all I can determine is that
15mf per hp is sometimes suggested..which would make my needs about
150 mf


Hanrahan discusses run caps in some detail. But the guidelines are
just a starting point. You still need to "balance" your RPC by
experiment, running the load for which you want it balanced because
it'll only be balanced for that load. A bigger idler requires less
balancing and is more tolerant of variations in load. But, like ya
say, ya run whut ya brung.


The big issue here..is that I built the 10hp RPC to run a 3ph mig
welder..which draws, full out..about 100 amps. I would be unlikely to
run that much juice though via the 70 amp breaker its connected too
G

That USA Mfg link is just the ticket. You figure Id be ok getting 4
of the 70 mf 240 vt caps, or should I go with a higher voltage cap?

Gunner

"Pax Americana is a philosophy. Hardly an empire.
Making sure other people play nice and dont kill each other (and us)
off in job lots is hardly empire building, particularly when you give
them self determination under "play nice" rules.

Think of it as having your older brother knock the **** out of you
for torturing the cat." Gunner

On Wed, 19 Oct 2005 07:58:33 GMT, in rec.crafts.metalworking you
wrote:

SNIP

APEX Electronics, 8909 San Fernando Rd.,

Sun Valley, CA, 91352

Tel: (818) 767-7202

Fax: (818) 767-1341

Web: http://www.apexelectronic.com

Email:
SNIP
Ayup...Ive been there before...but the City of Sun Valley has me on
the Banned list.
Im only allowed in there if accompanied by keepers, or by having a
long cable shackled to my leg and payed out via winch.

I guess having to send in the Search and Rescue teams..(3
actually..the first two got side tracked for a week or two after
someone suggested that they build a mobile command post from parts on
hand..and when they were found..the vehicle was about the size of a
pocket battleship) to find me again. Though Pizza Hut used the air
drops on the strobe for publicity purposes and were quite happy......

Gunner
XXXXXXXXXXXXXXXXXXXXXXXXXX
Hey Gunner,

Heh heh heh. I wore a hard hat after the first foray into that
jungle!! I think they use invisible sky hooks to keep the stuff "up".
Scary spot, but good for a 1/2 day excursion every visit to LA.

The caps were easy though. Just walk in the door, bear right to stay
parallel with SanFern road about 50 feet to the first "major"
intersection, turn left, two racks over, stuff is on the end, waist
high.

I kinda feel the "bit too high" prices at APEX are sort of like paying
to get into the zoo! I get $20 worth of entertainment for 4 hours "on
safari" (worth at least 5 bucks an hour), so I figure the caps only
cost 20 bucks, or evened out to 5 bucks each VBG.

My biggest worry was having my checked bags scanned at LAX, and
wondering if they would notice those "bomb looking thingys" (as my son
said), but there was no comment.

That USMfg place looks promising, but shipping from Indiana would just
about eat up the savings.

Take care.

Brian

On Wed, 19 Oct 2005 07:58:33 GMT, with neither quill nor qualm, Gunner
quickly quoth:

Ayup...Ive been there before...but the City of Sun Valley has me on
the Banned list.
Im only allowed in there if accompanied by keepers, or by having a
long cable shackled to my leg and payed out via winch.

I guess having to send in the Search and Rescue teams..(3
actually..the first two got side tracked for a week or two after
someone suggested that they build a mobile command post from parts on
hand..and when they were found..the vehicle was about the size of a
pocket battleship) to find me again. Though Pizza Hut used the air
drops on the strobe for publicity purposes and were quite happy......

OK, I'll bite. Give us the whole "Pizza Search & Rescue" story,
please. Sounds like a fun saga.


- - - - - - - - - - - - - - - - -
If God approved of nudity, we all would have been born naked.
----- ----- ----- ----- ----- -----
http://www.diversify.com Your Wild & Woody Website Wonk

On Wed, 19 Oct 2005 05:17:15 -0700, Larry Jaques
wrote:

On Wed, 19 Oct 2005 07:58:33 GMT, with neither quill nor qualm, Gunner
quickly quoth:

Ayup...Ive been there before...but the City of Sun Valley has me on
the Banned list.
Im only allowed in there if accompanied by keepers, or by having a
long cable shackled to my leg and payed out via winch.

I guess having to send in the Search and Rescue teams..(3
actually..the first two got side tracked for a week or two after
someone suggested that they build a mobile command post from parts on
hand..and when they were found..the vehicle was about the size of a
pocket battleship) to find me again. Though Pizza Hut used the air
drops on the strobe for publicity purposes and were quite happy......

OK, I'll bite. Give us the whole "Pizza Search & Rescue" story,
please. Sounds like a fun saga.


You really really need to come out and visit Apex.
Wear sensible shoes, carry a back pack with 72 hours of food and
water, increase your "incredulous factor" by at least an order of
magnitude, and a blue strobe is handy so they can deliver pizza and
chicken wings if you run out of food and water before you get to the
back section. Oh...and as Brian said...a hard hat is handy..along
with extra batteries for the head mounted lamp.

G

Gunner


- - - - - - - - - - - - - - - - -
If God approved of nudity, we all would have been born naked.
----- ----- ----- ----- ----- -----
http://www.diversify.com Your Wild & Woody Website Wonk

"Pax Americana is a philosophy. Hardly an empire.
Making sure other people play nice and dont kill each other (and us)
off in job lots is hardly empire building, particularly when you give
them self determination under "play nice" rules.

Think of it as having your older brother knock the **** out of you
for torturing the cat." Gunner

On Wed, 19 Oct 2005 17:28:05 GMT, with neither quill nor qualm, Gunner
quickly quoth:

On Wed, 19 Oct 2005 05:17:15 -0700, Larry Jaques
OK, I'll bite. Give us the whole "Pizza Search & Rescue" story,
please. Sounds like a fun saga.


You really really need to come out and visit Apex.

Huh? Is this a fertilizer story?
http://www.simplot.com/turf/apex/dis...california.cfm

This?
http://www.apexmachine.com/website/california.htm

This?
http://www.darp.noaa.gov/southwest/apex/

This?
http://www.volunteermatch.org/orgs/org44984.html


****, Gunner. Google has 2,060,000 hits for "apex california"...

I struck out on "apex survival california".

-----------------------------------------------
I'll apologize for offending someone...right
after they apologize for being easily offended.
-----------------------------------------------
http://www.diversify.com Inoffensive Web Design

On Wed, 19 Oct 2005 05:17:15 -0700, Larry Jaques
OK, I'll bite. Give us the whole "Pizza Search & Rescue" story,
please. Sounds like a fun saga.


You really really need to come out and visit Apex.

Huh? Is this a fertilizer story?
http://www.simplot.com/turf/apex/dis...california.cfm

This?
http://www.apexmachine.com/website/california.htm

This?
http://www.darp.noaa.gov/southwest/apex/

This?
http://www.volunteermatch.org/orgs/org44984.html


****, Gunner. Google has 2,060,000 hits for "apex california"...

I struck out on "apex survival california".

-----------------------------------------------
I'll apologize for offending someone...right
after they apologize for being easily offended.
-----------------------------------------------
http://www.diversify.com Inoffensive Web Design
XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX

Hey Larry,

Close, but no cigar!! Try the one I included in my first post to the
thread.

http://www.apexelectronic.com

The place is amazing. Anything from aluminum to zirconium, and the
only place I've ever seen nose sections of some kind of missile. I
understand (hearsay) that a lot of props for the movies are picked up
here. You could make a few thousand of the "Danger! Danger Will
Robinson!!" bots, or a pretty good semblance of the plane in Flight of
the Phoenix. And electronics gear and test gear is their forte.
Wire??? Never seen such piles an heaps of wire!! Stacks of IBM 360
computers. I was serious about it being a "jungle" though, complete
with a feeling of canopy overhead (the stuff is piled at least 12 feet
high)!! Something special you want, then just ask at the counter, if
you can find it! It's near the entrance someplace. Shout if you get
lost, and they'll send out a team or a homing signal.

Take care.

Brian Lawson,
Bothwell, Ontario.

On Wed, 19 Oct 2005 20:34:56 -0400, with neither quill nor qualm,
Brian Lawson quickly quoth:

On Wed, 19 Oct 2005 05:17:15 -0700, Larry Jaques
OK, I'll bite. Give us the whole "Pizza Search & Rescue" story,
please. Sounds like a fun saga.


You really really need to come out and visit Apex.

****, Gunner. Google has 2,060,000 hits for "apex california"...

I struck out on "apex survival california".

Hey Larry,

Close, but no cigar!! Try the one I included in my first post to the
thread.

http://www.apexelectronic.com

Ah, that's a little bit easier. I had missed seeing the original few
posts in that thread.


The place is amazing. Anything from aluminum to zirconium, and the
only place I've ever seen nose sections of some kind of missile. I
understand (hearsay) that a lot of props for the movies are picked up
here. You could make a few thousand of the "Danger! Danger Will
Robinson!!" bots, or a pretty good semblance of the plane in Flight of
the Phoenix. And electronics gear and test gear is their forte.
Wire??? Never seen such piles an heaps of wire!! Stacks of IBM 360
computers. I was serious about it being a "jungle" though, complete
with a feeling of canopy overhead (the stuff is piled at least 12 feet
high)!! Something special you want, then just ask at the counter, if
you can find it! It's near the entrance someplace. Shout if you get
lost, and they'll send out a team or a homing signal.

It must be big if you can see it all the way from the odd side of
Canuckistan!

-----------------------------------------------
I'll apologize for offending someone...right
after they apologize for being easily offended.
-----------------------------------------------
http://www.diversify.com Inoffensive Web Design

On 2005-10-18 07:20:57 -0700, "larry g" said:

I would assume that 370 VAC or higher voltage rating is what I want,
given start up surges and what not?

The minimum is 1.56 times the nominal line voltage.

This comes from ( ( 2 ) ^ 1/2 ) * 1.1 = 1.56 (to two decimal places).

( 2 ) ^ 1/2 converts RMS voltage to peak voltage (and assumes no
harmonics are present).

1.1 applies a 10% safety factor.

For a 240 line, the "precise" minimum us 373.35, but 370 is perfectly
acceptable.

Peter Haas wrote:

I would assume that 370 VAC or higher voltage rating is what I want,
given start up surges and what not?

The minimum is 1.56 times the nominal line voltage.

This comes from ( ( 2 ) ^ 1/2 ) * 1.1 = 1.56 (to two decimal places).

( 2 ) ^ 1/2 converts RMS voltage to peak voltage (and assumes no
harmonics are present).

1.1 applies a 10% safety factor.

For a 240 line, the "precise" minimum us 373.35, but 370 is perfectly
acceptable.

As I understand it, a capacitor rated for 370 VAC is rated for 370 VAC.
Now if the Capacitor is rated at 370 VDC, it may or may not be good
for 240 VAC. It depends on the foil thickness. A metalized foil cap
used for AC will heat up and fail prematurely.

I have some capacitors that are rated 600 volts DC or 330 volts AC 60
cycles. Note the AC rating is not the DC rating divided by 1.56. Also
note the rating is based on the frequency. The reason is that when DC
is applied to the capacitor, there is pretty much no heating caused by
the current in the capacitor.

Also note that the voltage rating for capacitors is based on a failure
rate at that voltage. I forget the numbers, but a home shop user is
not likely to ever come close to the number of hours that a capacitor
is expected to last. Consider that these are capacitors that are rated
for continuous use 24/7 for maybe 20 years.


Dan