17 Mar
2005
17 Mar
'05
4:19 p.m.
If I'm not
mistaken the whole reforming capacitors
discussion was for
electrolitic capacitors (ie DC). The motor run
capacitors are AC. I'm
not sure the reforming process would be the same
(or if it is even
> possible). 
17 Mar
17 Mar
4:29 p.m.
From: "William Maddox" <wmaddox at pacbell.net>
Are these capacitors electrolytics at all?
I thought that motor capacitors were generally
oil-filled, but not electrolytic.
They are oil-filled in my TU55, but they are electrolytic in my TU56.
Vince
The motor run
capacitors are AC. I'm
not sure the reforming process would be the same
(or if it is even
> possible). 
6:58 p.m.
Are these capacitors electrolytics at all?
I thought that motor capacitors were generally
oil-filled, but not electrolytic.
Nearly all are oil, but every so often you see an electrolytic
version. The oil caps will likely be good long after we are gone.
William Donzelli
aw288 at osfn.org
18 Mar
18 Mar
6:19 a.m.
>>>> "William" == William
Donzelli <aw288 at osfn.org> writes:
> Are these capacitors electrolytics at all? I
thought that motor
> capacitors were generally oil-filled, but not electrolytic.
William> Nearly all are oil, but every so often you see an
William> electrolytic version. The oil caps will likely be good long
William> after we are gone.
There are motor start caps and motor run caps. The former have much
higher capacitance and are only connected for a few seconds during
motor start. So my understanding is that start caps are often
electrolytic because you can get away with it, while run caps are not
because they are subjected to AC full time.
paul
6:58 a.m.
From: "Paul Koning" <pkoning at equallogic.com>
What you are saying is consistent with what I see on most sites selling
these things. There, "run" caps are generally oil, and "start" caps
are
generally electrolytic. The exception being the occasional "start/run" cap,
whatever that is.
The original caps in the TU56 are high capacitance, and clearly
electrolytic. But they appear to be wired for continuous phase shifting
duty. Hence some of the people on the list insisting that they are "run"
caps, and that the beefier, more expensive "run" cap should be used.
Finding a 100uf oil-filled "run" cap is not easy, and they tend to be
expensive (as Jay pointed out).
Unfortunately, I do not have any insight as to whether the relatively
inexpensive electrolytics can be used, or whether the expensive oil-filled
caps are needed.
The TU55 uses a 7uf oil capacitor in this role, which again argues for a
"run" capacitor, except the values are wildly different. Is it possible
"start" caps were used in the TU56 to save $$, but are being derated somehow
so they can be used as "run" caps??
Vince
>>>> "William" == William Donzelli <aw288 at osfn.org> writes:
> Are these capacitors electrolytics at all? I
thought that motor
> capacitors were generally oil-filled, but not electrolytic.
William> Nearly all are oil, but every so often you see an
William> electrolytic version. The oil caps will likely be good long
William> after we are gone.
There are motor start caps and motor run caps. The former have much
higher capacitance and are only connected for a few seconds during
motor start. So my understanding is that start caps are often
electrolytic because you can get away with it, while run caps are not
because they are subjected to AC full time.
8:56 a.m.
Unfortunately, I do not have any insight as to whether
the relatively
inexpensive electrolytics can be used, or whether the expensive oil-filled
caps are needed.
"Normal" electrolytics (as in inexpesive filter caps) probably will not
work well at all. They probably would not last long, anyway.
William Donzelli
aw288 at osfn.org
9:15 a.m.
From: "William Donzelli" <aw288 at osfn.org>
Sure, but how long would an electrolytic rated for motor start applications
be expected to last? Those are still 10x cheaper than the oil-filled jobs.
Vince
> Unfortunately, I do not have any insight as to
whether the relatively
> inexpensive electrolytics can be used, or whether the expensive
oil-filled
caps are
needed.
"Normal" electrolytics (as in inexpesive filter caps) probably will not
work well at all. They probably would not last long, anyway. 
10:53 a.m.
vrs wrote:
What you are saying is consistent with what I see on
most sites selling
these things. There, "run" caps are generally oil, and "start" caps
are
generally electrolytic. The exception being the occasional "start/run" cap,
whatever that is.
The original caps in the TU56 are high capacitance, and clearly
electrolytic. But they appear to be wired for continuous phase shifting
duty. Hence some of the people on the list insisting that they are "run"
caps, and that the beefier, more expensive "run" cap should be used.
Finding a 100uf oil-filled "run" cap is not easy, and they tend to be
expensive (as Jay pointed out).
Well they are more around I think do to the vacumm tube audio field and
may want to look there.
http://www.percyaudio.com/ some nice NEW caps here. Still about $50
for 100uf.
The TU55 uses a 7uf oil capacitor in this role, which
again argues for a
"run" capacitor, except the values are wildly different. Is it possible
"start" caps were used in the TU56 to save $$, but are being derated somehow
so they can be used as "run" caps??
19 Mar
19 Mar
1:25 p.m.
On Fri, 18 Mar 2005 06:58:59 -0800
"vrs" <vrs at msn.com> wrote:
Finding a 100uf oil-filled "run" cap is not
easy, and they tend to be
expensive (as Jay pointed out).
Often, older oil-filled capacitors will have the 'nasty' oil in them
containing carcingenic PCBs, which is part of what makes oil-filled caps
hard to find. I've often pondered on that fact with the big caps one
sees at surplus stores. I.e.: which are the ones that transform your
home into a mini-superfund site if you cut them open?
1:53 p.m.
Often, older oil-filled capacitors will have the
'nasty' oil in them
containing carcingenic PCBs, which is part of what makes oil-filled caps
hard to find. I've often pondered on that fact with the big caps one
sees at surplus stores. I.e.: which are the ones that transform your
home into a mini-superfund site if you cut them open?
The oil found in some* caps is carcinogenic, but it is really not all that
bad if you spill a little on yourself. You really need to be exposed to
the stuff for a very long time for the cancer spectre to come up. About
the worst you could do to yourself with a little spill is a good slip on
the floor and a sore behind.
The real danger of oil caps is when they burn - the resulting fumes are
NOT nice (dioxin compounds, I think). Just the little oil in a few motor
start (errrr...run) caps won't really cause too many problems. If the caps
are burning, which they do not do well, probably plenty of other things
are buring with them, at which point you have a serious fire and plenty of
other fumes to worry about.
* A large percentage are not PCB filled. Just because a cap doesn't say
"NO PCBS", does in mean it has them. Many non-PCB caps were made before
the "NO PCBS" label came into force.
William Donzelli
aw288 at osfn.org
2:45 p.m.
>>>> "William" == William
Donzelli <aw288 at osfn.org> writes:
> Often, older oil-filled capacitors will have the
'nasty' oil in
> them containing carcingenic PCBs, which is part of what makes
> oil-filled caps hard to find. I've often pondered on that fact
> with the big caps one sees at surplus stores. I.e.: which are the
> ones that transform your home into a mini-superfund site if you
> cut them open?
William> The oil found in some* caps is carcinogenic, but it is
William> really not all that bad if you spill a little on
William> yourself. You really need to be exposed to the stuff for a
William> very long time for the cancer spectre to come up. About the
William> worst you could do to yourself with a little spill is a good
William> slip on the floor and a sore behind.
William> The real danger of oil caps is when they burn - the
William> resulting fumes are NOT nice (dioxin compounds, I
William> think). Just the little oil in a few motor start
William> (errrr...run) caps won't really cause too many problems. If
William> the caps are burning, which they do not do well, probably
William> plenty of other things are buring with them, at which point
William> you have a serious fire and plenty of other fumes to worry
William> about.
If I remember right, dioxins are substances known to be extremely
dangerous to guinea pigs, slightly toxic to rats, and maybe not at all
to most other mammals...
The most important property of PCBs and dioxins is that they provide
infinite employment to lawyers of all kinds.
William> * A large percentage are not PCB filled. Just because a cap
William> doesn't say "NO PCBS", does in mean it has them. Many
William> non-PCB caps were made before the "NO PCBS" label came into
William> force.
That makes sense. I thougth PCBs were used because of nice thermal
properties -- which is great for power transformers, but not so
obviously important for capacitors.
paul
20 Mar
20 Mar
2:36 a.m.
On Sun, 20 Mar 2005 02:33:01 +0100, Eric Smith <eric at brouhaha.com> wrote:
Paul wrote:
The clue here is that media want you to believe there is a single
substance called "dioxin", just like this dangerous "atom" thing.
Dioxins are as different as, say, alcohols or acids.
I understand from a friend who is doing research in biochemistry, that a
couple of dioxins are harmful to people. They are not all that easy to
produce.
On the other hand, anything is harmful in big enough doses. I think
Yushenko got a dose several million times what you get from working all
your life in an incinerator.
--
-bv
If I remember right, dioxins are substances known
to be extremely
dangerous to guinea pigs, slightly toxic to rats, and maybe not at all
to most other mammals...
I'm sure that's very comforting to Viktor Yushchenko, who is suffering
from dioxin poisoning.
19 Mar
19 Mar
5:40 p.m.
I've found C and H surplus here in California to be an excellent source for
all kinds of semi-exotic parts ( like capacitors ) for old Tek and HP test
equipment, old computers, Tesla Coils and Ham Radio gear. Their link is
below and they have a great catalog they'll send you for free. If you call
them they will do there best to help you and not just try to get you off the
phone. They are located in Pasadena and will ship to just about anywhere (
except the International Space Station ).
Best regards, and good luck, Steven C.
2 Apr
2 Apr
5 p.m.
Sorry, another case of the elusive disappearing link. C and H can be had at:
www.candhsales.com or 1-800-325-9465.
I'll blame it on a prostate condition....
Regards, Steven C.
I've found C and H surplus here in California to
be an excellent source
for
all kinds of semi-exotic parts ( like capacitors ) for
old Tek and HP test
equipment, old computers, Tesla Coils and Ham Radio gear. Their link is
below and they have a great catalog they'll send you for free. If you call
them they will do there best to help you and not just try to get you off
the
phone. They are located in Pasadena and will ship to
just about anywhere (
except the International Space Station ).
Best regards, and good luck, Steven C.
5 Apr
5 Apr
12:32 a.m.
Sorry, another case of the elusive disappearing link. C and H can be had at:
www.candhsales.com or 1-800-325-9465.
I'll blame it on a prostate condition....
Regards, Steven C.
I've found C and H surplus here in California to
be an excellent source
for
all kinds of semi-exotic parts ( like capacitors ) for
old Tek and HP test
equipment, old computers, Tesla Coils and Ham Radio gear. Their link is
below and they have a great catalog they'll send you for free. If you call
them they will do there best to help you and not just try to get you off
the
phone. They are located in Pasadena and will ship to
just about anywhere (
except the International Space Station ).
Best regards, and good luck, Steven C.
18 Mar
18 Mar
8:50 a.m.
There are motor start caps and motor run caps. The
former have much
higher capacitance and are only connected for a few seconds during
motor start. So my understanding is that start caps are often
electrolytic because you can get away with it, while run caps are not
because they are subjected to AC full time.
Very true, but either case is pretty hostile, electrically (especially on
larger motors).
William Donzelli
aw288 at osfn.org
6973
days inactive
6991
days old
16 comments
9 participants
participants (9)
-
aw288＠osfn.org -
bfranchuk＠jetnet.ab.ca -
bv＠norbionics.com -
cannings＠earthlink.net -
chenmel＠earthlink.net -
eric＠brouhaha.com -
pkoning＠equallogic.com -
vrs＠msn.com -
wmaddox＠pacbell.net