A to D conversion...
Archiver
Posts: 46,084
Hey folks,
Discovered today how easy A to D conversion can be. This is going to help a
lot in designing the Data Logger I'm thinking about.
See the url below for a demo circuit and code. Click on A to D Converter.
http://www.lennard.net.nz/electronics/electronics.html
cheers,
Ben, Wellington, New Zealand.
--
http://www.lennard.net.nz/
Ben Lennard, NCEE, Dip EE
Web Hosting and Electronics R&D
Hm: +64 4 972 7567
Mb: +64 21 536 627
87 Spencer Street
Crofton Downs
Wellington
New Zealand
"To the optimist, the glass is half full. To the pessimist, the glass is
half empty. To the engineer, the glass is twice as big as it needs to be."
No animals were harmed in the transmission of this email, although the
Dog next door is living on borrowed time, let me tell you! Those of you
with an overwhelming fear of the unknown will be gratified to learn that
there is no hidden message revealed by reading this warning backwards.
>From: Leroy Hall <leroy@f...>
>To: basicstamps@yahoogroups.com
>Subject: Re: [noparse][[/noparse]basicstamps] Any Power Engineers Lurking?
>Date: Tue, 21 May 2002 5:52 AM
>
> I think I understand your situation a little better than what was
> before. I assumed you were using commercial equipment, a mistake on my
> part. Your statement, "I am trying to assess the net effect on the
> primary side of the coupling transformer, i.e.: as long as the rectifier
> is fairly well balanced, there should be no DC reflected back, right?"
> is new to me. I have heard of power reflected in an RF radio type
> situation, we call it SWR. But I have not heard of DC being reflected
> back across the winding of a x-former. MAybe we could discuss the
> situation off list. if you like. Sounds interesting at the very
> least.. I consider myself more a controls engineer, in that I have
> expertise in PLC.s but power control is also very interesting although
> my experience there is limited more to the theoretical rather than the
> practical side. Good luck..
>
> Leroy
>
> "Chris Loiacono (E-mail)" wrote:
>>
>> I have an AC Phase-angle power controller design that I am trying to fit to
>> a customer's application.
>> I mention it here because there are experts here in every field, it seems,
>> although the part of it I'm working on is basically an AC Power EE problem:
>>
>> The controller fires gates on SCR/Diode pairs on each leg of a three phase
>> load. The zero-crossing timing is derived optically from the AC line, and
>> the command input to the PIC sets the gate delay, or phase angle to fire at.
>> It was intended for resistive loads, where the relationship between voltage
>> and current is quite simple.
>>
>> I need to use it to gate the SCR's into a transformer primary, which is a
>> simple 3-wire delta. The secondary is through a three-phase bridge rectifier
>> to a wye connected resistive load. You might envision it feeding the
>> resistive equivalent of a 3-phase AC motor stator, but ignore the concept of
>> motion.
>>
>> I am trying to assess the net effect on the primary side of the coupling
>> transformer, ie: as long as the rectifier is fairly well balanced, there
>> should be no DC reflected back, right?
>> Will the current at the transformer primary lag, and will that effect my
>> zero-cross detect timing, since it is done by LED's? If so, the controller
>> will fire past the zero-crossings and make some spectacular fireworks, since
>> it deals with hundreds of Volts at hundreds of Amps.
>>
>> Please let me know if anyone has experience with this sort of thing that
>> would like to discuss it either on or off-list.
>>
>> Chris
>>
>> To UNSUBSCRIBE, just send mail to:
>> basicstamps-unsubscribe@yahoogroups.com
>> from the same email address that you subscribed. Text in the Subject and
> Body of the message will be ignored.
>>
>>
>> Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/
>
> To UNSUBSCRIBE, just send mail to:
> basicstamps-unsubscribe@yahoogroups.com
> from the same email address that you subscribed. Text in the Subject and
> Body of the message will be ignored.
>
>
> Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/
>
>
Discovered today how easy A to D conversion can be. This is going to help a
lot in designing the Data Logger I'm thinking about.
See the url below for a demo circuit and code. Click on A to D Converter.
http://www.lennard.net.nz/electronics/electronics.html
cheers,
Ben, Wellington, New Zealand.
--
http://www.lennard.net.nz/
Ben Lennard, NCEE, Dip EE
Web Hosting and Electronics R&D
Hm: +64 4 972 7567
Mb: +64 21 536 627
87 Spencer Street
Crofton Downs
Wellington
New Zealand
"To the optimist, the glass is half full. To the pessimist, the glass is
half empty. To the engineer, the glass is twice as big as it needs to be."
No animals were harmed in the transmission of this email, although the
Dog next door is living on borrowed time, let me tell you! Those of you
with an overwhelming fear of the unknown will be gratified to learn that
there is no hidden message revealed by reading this warning backwards.
>From: Leroy Hall <leroy@f...>
>To: basicstamps@yahoogroups.com
>Subject: Re: [noparse][[/noparse]basicstamps] Any Power Engineers Lurking?
>Date: Tue, 21 May 2002 5:52 AM
>
> I think I understand your situation a little better than what was
> before. I assumed you were using commercial equipment, a mistake on my
> part. Your statement, "I am trying to assess the net effect on the
> primary side of the coupling transformer, i.e.: as long as the rectifier
> is fairly well balanced, there should be no DC reflected back, right?"
> is new to me. I have heard of power reflected in an RF radio type
> situation, we call it SWR. But I have not heard of DC being reflected
> back across the winding of a x-former. MAybe we could discuss the
> situation off list. if you like. Sounds interesting at the very
> least.. I consider myself more a controls engineer, in that I have
> expertise in PLC.s but power control is also very interesting although
> my experience there is limited more to the theoretical rather than the
> practical side. Good luck..
>
> Leroy
>
> "Chris Loiacono (E-mail)" wrote:
>>
>> I have an AC Phase-angle power controller design that I am trying to fit to
>> a customer's application.
>> I mention it here because there are experts here in every field, it seems,
>> although the part of it I'm working on is basically an AC Power EE problem:
>>
>> The controller fires gates on SCR/Diode pairs on each leg of a three phase
>> load. The zero-crossing timing is derived optically from the AC line, and
>> the command input to the PIC sets the gate delay, or phase angle to fire at.
>> It was intended for resistive loads, where the relationship between voltage
>> and current is quite simple.
>>
>> I need to use it to gate the SCR's into a transformer primary, which is a
>> simple 3-wire delta. The secondary is through a three-phase bridge rectifier
>> to a wye connected resistive load. You might envision it feeding the
>> resistive equivalent of a 3-phase AC motor stator, but ignore the concept of
>> motion.
>>
>> I am trying to assess the net effect on the primary side of the coupling
>> transformer, ie: as long as the rectifier is fairly well balanced, there
>> should be no DC reflected back, right?
>> Will the current at the transformer primary lag, and will that effect my
>> zero-cross detect timing, since it is done by LED's? If so, the controller
>> will fire past the zero-crossings and make some spectacular fireworks, since
>> it deals with hundreds of Volts at hundreds of Amps.
>>
>> Please let me know if anyone has experience with this sort of thing that
>> would like to discuss it either on or off-list.
>>
>> Chris
>>
>> To UNSUBSCRIBE, just send mail to:
>> basicstamps-unsubscribe@yahoogroups.com
>> from the same email address that you subscribed. Text in the Subject and
> Body of the message will be ignored.
>>
>>
>> Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/
>
> To UNSUBSCRIBE, just send mail to:
> basicstamps-unsubscribe@yahoogroups.com
> from the same email address that you subscribed. Text in the Subject and
> Body of the message will be ignored.
>
>
> Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/
>
>
Comments
from the TLC548CP pointing at the 47k resistor?
Don
Original Message
From: "Ben Lennard" <postmaster@s...>
To: <basicstamps@yahoogroups.com>
Sent: Thursday, May 23, 2002 4:41 AM
Subject: [noparse][[/noparse]basicstamps] A to D conversion...
> Hey folks,
>
> Discovered today how easy A to D conversion can be. This is going to help
a
> lot in designing the Data Logger I'm thinking about.
> See the url below for a demo circuit and code. Click on A to D Converter.
>
> http://www.lennard.net.nz/electronics/electronics.html
>
> cheers,
>
> Ben, Wellington, New Zealand.
>
> --
> http://www.lennard.net.nz/
> Ben Lennard, NCEE, Dip EE
>
> Web Hosting and Electronics R&D
>
> Hm: +64 4 972 7567
> Mb: +64 21 536 627
> 87 Spencer Street
> Crofton Downs
> Wellington
> New Zealand
>
> "To the optimist, the glass is half full. To the pessimist, the glass is
> half empty. To the engineer, the glass is twice as big as it needs to
be."
>
> No animals were harmed in the transmission of this email, although the
> Dog next door is living on borrowed time, let me tell you! Those of you
> with an overwhelming fear of the unknown will be gratified to learn that
> there is no hidden message revealed by reading this warning backwards.
>
>
>
>
>
> >From: Leroy Hall <leroy@f...>
> >To: basicstamps@yahoogroups.com
> >Subject: Re: [noparse][[/noparse]basicstamps] Any Power Engineers Lurking?
> >Date: Tue, 21 May 2002 5:52 AM
> >
>
> > I think I understand your situation a little better than what was
> > before. I assumed you were using commercial equipment, a mistake on my
> > part. Your statement, "I am trying to assess the net effect on the
> > primary side of the coupling transformer, i.e.: as long as the rectifier
> > is fairly well balanced, there should be no DC reflected back, right?"
> > is new to me. I have heard of power reflected in an RF radio type
> > situation, we call it SWR. But I have not heard of DC being reflected
> > back across the winding of a x-former. MAybe we could discuss the
> > situation off list. if you like. Sounds interesting at the very
> > least.. I consider myself more a controls engineer, in that I have
> > expertise in PLC.s but power control is also very interesting although
> > my experience there is limited more to the theoretical rather than the
> > practical side. Good luck..
> >
> > Leroy
> >
> > "Chris Loiacono (E-mail)" wrote:
> >>
> >> I have an AC Phase-angle power controller design that I am trying to
fit to
> >> a customer's application.
> >> I mention it here because there are experts here in every field, it
seems,
> >> although the part of it I'm working on is basically an AC Power EE
problem:
> >>
> >> The controller fires gates on SCR/Diode pairs on each leg of a three
phase
> >> load. The zero-crossing timing is derived optically from the AC line,
and
> >> the command input to the PIC sets the gate delay, or phase angle to
fire at.
> >> It was intended for resistive loads, where the relationship between
voltage
> >> and current is quite simple.
> >>
> >> I need to use it to gate the SCR's into a transformer primary, which is
a
> >> simple 3-wire delta. The secondary is through a three-phase bridge
rectifier
> >> to a wye connected resistive load. You might envision it feeding the
> >> resistive equivalent of a 3-phase AC motor stator, but ignore the
concept of
> >> motion.
> >>
> >> I am trying to assess the net effect on the primary side of the
coupling
> >> transformer, ie: as long as the rectifier is fairly well balanced,
there
> >> should be no DC reflected back, right?
> >> Will the current at the transformer primary lag, and will that effect
my
> >> zero-cross detect timing, since it is done by LED's? If so, the
controller
> >> will fire past the zero-crossings and make some spectacular fireworks,
since
> >> it deals with hundreds of Volts at hundreds of Amps.
> >>
> >> Please let me know if anyone has experience with this sort of thing
that
> >> would like to discuss it either on or off-list.
> >>
> >> Chris
> >>
> >> To UNSUBSCRIBE, just send mail to:
> >> basicstamps-unsubscribe@yahoogroups.com
> >> from the same email address that you subscribed. Text in the Subject
and
> > Body of the message will be ignored.
> >>
> >>
> >> Your use of Yahoo! Groups is subject to
http://docs.yahoo.com/info/terms/
> >
> > To UNSUBSCRIBE, just send mail to:
> > basicstamps-unsubscribe@yahoogroups.com
> > from the same email address that you subscribed. Text in the Subject
and
> > Body of the message will be ignored.
> >
> >
> > Your use of Yahoo! Groups is subject to
http://docs.yahoo.com/info/terms/
> >
> >
>
> To UNSUBSCRIBE, just send mail to:
> basicstamps-unsubscribe@yahoogroups.com
> from the same email address that you subscribed. Text in the Subject and
Body of the message will be ignored.
>
>
> Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/
>
>
>
normally the middle pin.
>From: "Don" <renegade.engineer@v...>
>Reply-To: basicstamps@yahoogroups.com
>To: <basicstamps@yahoogroups.com>
>Subject: Re: [noparse][[/noparse]basicstamps] A to D conversion...
>Date: Thu, 23 May 2002 07:40:42 -0700
>
> Ben, in the diagram on that link, what is the significance of the
>arrow
>from the TLC548CP pointing at the 47k resistor?
>Don
>
Original Message
>From: "Ben Lennard" <postmaster@s...>
>To: <basicstamps@yahoogroups.com>
>Sent: Thursday, May 23, 2002 4:41 AM
>Subject: [noparse][[/noparse]basicstamps] A to D conversion...
>
>
> > Hey folks,
> >
> > Discovered today how easy A to D conversion can be. This is going to
>help
>a
> > lot in designing the Data Logger I'm thinking about.
> > See the url below for a demo circuit and code. Click on A to D
>Converter.
> >
> > http://www.lennard.net.nz/electronics/electronics.html
> >
> > cheers,
> >
> > Ben, Wellington, New Zealand.
> >
> > --
> > http://www.lennard.net.nz/
> > Ben Lennard, NCEE, Dip EE
> >
> > Web Hosting and Electronics R&D
> >
> > Hm: +64 4 972 7567
> > Mb: +64 21 536 627
> > 87 Spencer Street
> > Crofton Downs
> > Wellington
> > New Zealand
> >
> > "To the optimist, the glass is half full. To the pessimist, the glass
>is
> > half empty. To the engineer, the glass is twice as big as it needs to
>be."
> >
> > No animals were harmed in the transmission of this email, although the
> > Dog next door is living on borrowed time, let me tell you! Those of you
> > with an overwhelming fear of the unknown will be gratified to learn that
> > there is no hidden message revealed by reading this warning backwards.
> >
> >
> >
> >
> >
> > >From: Leroy Hall <leroy@f...>
> > >To: basicstamps@yahoogroups.com
> > >Subject: Re: [noparse][[/noparse]basicstamps] Any Power Engineers Lurking?
> > >Date: Tue, 21 May 2002 5:52 AM
> > >
> >
> > > I think I understand your situation a little better than what was
> > > before. I assumed you were using commercial equipment, a mistake on my
> > > part. Your statement, "I am trying to assess the net effect on the
> > > primary side of the coupling transformer, i.e.: as long as the
>rectifier
> > > is fairly well balanced, there should be no DC reflected back, right?"
> > > is new to me. I have heard of power reflected in an RF radio type
> > > situation, we call it SWR. But I have not heard of DC being reflected
> > > back across the winding of a x-former. MAybe we could discuss the
> > > situation off list. if you like. Sounds interesting at the very
> > > least.. I consider myself more a controls engineer, in that I have
> > > expertise in PLC.s but power control is also very interesting although
> > > my experience there is limited more to the theoretical rather than the
> > > practical side. Good luck..
> > >
> > > Leroy
> > >
> > > "Chris Loiacono (E-mail)" wrote:
> > >>
> > >> I have an AC Phase-angle power controller design that I am trying to
>fit to
> > >> a customer's application.
> > >> I mention it here because there are experts here in every field, it
>seems,
> > >> although the part of it I'm working on is basically an AC Power EE
>problem:
> > >>
> > >> The controller fires gates on SCR/Diode pairs on each leg of a three
>phase
> > >> load. The zero-crossing timing is derived optically from the AC line,
>and
> > >> the command input to the PIC sets the gate delay, or phase angle to
>fire at.
> > >> It was intended for resistive loads, where the relationship between
>voltage
> > >> and current is quite simple.
> > >>
> > >> I need to use it to gate the SCR's into a transformer primary, which
>is
>a
> > >> simple 3-wire delta. The secondary is through a three-phase bridge
>rectifier
> > >> to a wye connected resistive load. You might envision it feeding the
> > >> resistive equivalent of a 3-phase AC motor stator, but ignore the
>concept of
> > >> motion.
> > >>
> > >> I am trying to assess the net effect on the primary side of the
>coupling
> > >> transformer, ie: as long as the rectifier is fairly well balanced,
>there
> > >> should be no DC reflected back, right?
> > >> Will the current at the transformer primary lag, and will that effect
>my
> > >> zero-cross detect timing, since it is done by LED's? If so, the
>controller
> > >> will fire past the zero-crossings and make some spectacular
>fireworks,
>since
> > >> it deals with hundreds of Volts at hundreds of Amps.
> > >>
> > >> Please let me know if anyone has experience with this sort of thing
>that
> > >> would like to discuss it either on or off-list.
> > >>
> > >> Chris
> > >>
> > >> To UNSUBSCRIBE, just send mail to:
> > >> basicstamps-unsubscribe@yahoogroups.com
> > >> from the same email address that you subscribed. Text in the Subject
>and
> > > Body of the message will be ignored.
> > >>
> > >>
> > >> Your use of Yahoo! Groups is subject to
>http://docs.yahoo.com/info/terms/
> > >
> > > To UNSUBSCRIBE, just send mail to:
> > > basicstamps-unsubscribe@yahoogroups.com
> > > from the same email address that you subscribed. Text in the Subject
>and
> > > Body of the message will be ignored.
> > >
> > >
> > > Your use of Yahoo! Groups is subject to
>http://docs.yahoo.com/info/terms/
> > >
> > >
> >
> > To UNSUBSCRIBE, just send mail to:
> > basicstamps-unsubscribe@yahoogroups.com
> > from the same email address that you subscribed. Text in the Subject
>and
>Body of the message will be ignored.
> >
> >
> > Your use of Yahoo! Groups is subject to
>http://docs.yahoo.com/info/terms/
> >
> >
> >
>
>
>
>To UNSUBSCRIBE, just send mail to:
> basicstamps-unsubscribe@yahoogroups.com
>from the same email address that you subscribed. Text in the Subject and
>Body of the message will be ignored.
>
>
>Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/
>
>
_________________________________________________________________
Meld je aan bij de grootste e-mailservice wereldwijd met MSN Hotmail:
http://www.hotmail.com/nl
here. Look at
http://www.lennard.net.nz/electronics/ad.html
The arrow in question appears to be connected to the A-D converter chip, but
there is no pin identification associated with the IC. If it were meant to
indicate a variable resistor, I would expect the arrow to pass through the
resistor and not show an apparent physical connection to another device. To
me, the drawing seems to indicate a standard resistor, as it doesn't
indicate a high-low range for the resistor.
Don
Original Message
From: "SX-2 commander" <sx2_commander@h...>
To: <basicstamps@yahoogroups.com>
Sent: Thursday, May 23, 2002 9:11 AM
Subject: Re: [noparse][[/noparse]basicstamps] A to D conversion...
>
> An arrow in an resistor means it is a variable resistor. Physical, it is
> normally the middle pin.
>
> >From: "Don" <renegade.engineer@v...>
> >Reply-To: basicstamps@yahoogroups.com
> >To: <basicstamps@yahoogroups.com>
> >Subject: Re: [noparse][[/noparse]basicstamps] A to D conversion...
> >Date: Thu, 23 May 2002 07:40:42 -0700
> >
> > Ben, in the diagram on that link, what is the significance of the
> >arrow
> >from the TLC548CP pointing at the 47k resistor?
> >Don
> >
Original Message
> >From: "Ben Lennard" <postmaster@s...>
> >To: <basicstamps@yahoogroups.com>
> >Sent: Thursday, May 23, 2002 4:41 AM
> >Subject: [noparse][[/noparse]basicstamps] A to D conversion...
> >
> >
> > > Hey folks,
> > >
> > > Discovered today how easy A to D conversion can be. This is going to
> >help
> >a
> > > lot in designing the Data Logger I'm thinking about.
> > > See the url below for a demo circuit and code. Click on A to D
> >Converter.
> > >
> > > http://www.lennard.net.nz/electronics/electronics.html
> > >
> > > cheers,
> > >
> > > Ben, Wellington, New Zealand.
> > >
> > > --
> > > http://www.lennard.net.nz/
> > > Ben Lennard, NCEE, Dip EE
> > >
> > > Web Hosting and Electronics R&D
> > >
> > > Hm: +64 4 972 7567
> > > Mb: +64 21 536 627
> > > 87 Spencer Street
> > > Crofton Downs
> > > Wellington
> > > New Zealand
> > >
> > > "To the optimist, the glass is half full. To the pessimist, the glass
> >is
> > > half empty. To the engineer, the glass is twice as big as it needs to
> >be."
> > >
> > > No animals were harmed in the transmission of this email, although the
> > > Dog next door is living on borrowed time, let me tell you! Those of
you
> > > with an overwhelming fear of the unknown will be gratified to learn
that
> > > there is no hidden message revealed by reading this warning backwards.
> > >
> > >
> > >
> > >
> > >
> > > >From: Leroy Hall <leroy@f...>
> > > >To: basicstamps@yahoogroups.com
> > > >Subject: Re: [noparse][[/noparse]basicstamps] Any Power Engineers Lurking?
> > > >Date: Tue, 21 May 2002 5:52 AM
> > > >
> > >
> > > > I think I understand your situation a little better than what was
> > > > before. I assumed you were using commercial equipment, a mistake on
my
> > > > part. Your statement, "I am trying to assess the net effect on the
> > > > primary side of the coupling transformer, i.e.: as long as the
> >rectifier
> > > > is fairly well balanced, there should be no DC reflected back,
right?"
> > > > is new to me. I have heard of power reflected in an RF radio type
> > > > situation, we call it SWR. But I have not heard of DC being
reflected
> > > > back across the winding of a x-former. MAybe we could discuss the
> > > > situation off list. if you like. Sounds interesting at the very
> > > > least.. I consider myself more a controls engineer, in that I have
> > > > expertise in PLC.s but power control is also very interesting
although
> > > > my experience there is limited more to the theoretical rather than
the
> > > > practical side. Good luck..
> > > >
> > > > Leroy
> > > >
> > > > "Chris Loiacono (E-mail)" wrote:
> > > >>
> > > >> I have an AC Phase-angle power controller design that I am trying
to
> >fit to
> > > >> a customer's application.
> > > >> I mention it here because there are experts here in every field, it
> >seems,
> > > >> although the part of it I'm working on is basically an AC Power EE
> >problem:
> > > >>
> > > >> The controller fires gates on SCR/Diode pairs on each leg of a
three
> >phase
> > > >> load. The zero-crossing timing is derived optically from the AC
line,
> >and
> > > >> the command input to the PIC sets the gate delay, or phase angle to
> >fire at.
> > > >> It was intended for resistive loads, where the relationship between
> >voltage
> > > >> and current is quite simple.
> > > >>
> > > >> I need to use it to gate the SCR's into a transformer primary,
which
> >is
> >a
> > > >> simple 3-wire delta. The secondary is through a three-phase bridge
> >rectifier
> > > >> to a wye connected resistive load. You might envision it feeding
the
> > > >> resistive equivalent of a 3-phase AC motor stator, but ignore the
> >concept of
> > > >> motion.
> > > >>
> > > >> I am trying to assess the net effect on the primary side of the
> >coupling
> > > >> transformer, ie: as long as the rectifier is fairly well balanced,
> >there
> > > >> should be no DC reflected back, right?
> > > >> Will the current at the transformer primary lag, and will that
effect
> >my
> > > >> zero-cross detect timing, since it is done by LED's? If so, the
> >controller
> > > >> will fire past the zero-crossings and make some spectacular
> >fireworks,
> >since
> > > >> it deals with hundreds of Volts at hundreds of Amps.
> > > >>
> > > >> Please let me know if anyone has experience with this sort of thing
> >that
> > > >> would like to discuss it either on or off-list.
> > > >>
> > > >> Chris
> > > >>
> > > >> To UNSUBSCRIBE, just send mail to:
> > > >> basicstamps-unsubscribe@yahoogroups.com
> > > >> from the same email address that you subscribed. Text in the
Subject
> >and
> > > > Body of the message will be ignored.
> > > >>
> > > >>
> > > >> Your use of Yahoo! Groups is subject to
> >http://docs.yahoo.com/info/terms/
> > > >
> > > > To UNSUBSCRIBE, just send mail to:
> > > > basicstamps-unsubscribe@yahoogroups.com
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Subject
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>
>
chip handy to give you a pin number
Don wrote:
> Yes, I know about variable resistors, but I'm not sure that is the case
> here. Look at
> http://www.lennard.net.nz/electronics/ad.html
> The arrow in question appears to be connected to the A-D converter chip, but
> there is no pin identification associated with the IC. If it were meant to
> indicate a variable resistor, I would expect the arrow to pass through the
> resistor and not show an apparent physical connection to another device. To
> me, the drawing seems to indicate a standard resistor, as it doesn't
> indicate a high-low range for the resistor.
> Don
>
Original Message
> From: "SX-2 commander" <sx2_commander@h...>
> To: <basicstamps@yahoogroups.com>
> Sent: Thursday, May 23, 2002 9:11 AM
> Subject: Re: [noparse][[/noparse]basicstamps] A to D conversion...
>
> >
> > An arrow in an resistor means it is a variable resistor. Physical, it is
> > normally the middle pin.
> >
> > >From: "Don" <renegade.engineer@v...>
> > >Reply-To: basicstamps@yahoogroups.com
> > >To: <basicstamps@yahoogroups.com>
> > >Subject: Re: [noparse][[/noparse]basicstamps] A to D conversion...
> > >Date: Thu, 23 May 2002 07:40:42 -0700
> > >
> > > Ben, in the diagram on that link, what is the significance of the
> > >arrow
> > >from the TLC548CP pointing at the 47k resistor?
> > >Don
> > >
Original Message
> > >From: "Ben Lennard" <postmaster@s...>
> > >To: <basicstamps@yahoogroups.com>
> > >Sent: Thursday, May 23, 2002 4:41 AM
> > >Subject: [noparse][[/noparse]basicstamps] A to D conversion...
> > >
> > >
> > > > Hey folks,
> > > >
> > > > Discovered today how easy A to D conversion can be. This is going to
> > >help
> > >a
> > > > lot in designing the Data Logger I'm thinking about.
> > > > See the url below for a demo circuit and code. Click on A to D
> > >Converter.
> > > >
> > > > http://www.lennard.net.nz/electronics/electronics.html
> > > >
> > > > cheers,
> > > >
> > > > Ben, Wellington, New Zealand.
> > > >
> > > > --
> > > > http://www.lennard.net.nz/
> > > > Ben Lennard, NCEE, Dip EE
> > > >
> > > > Web Hosting and Electronics R&D
> > > >
> > > > Hm: +64 4 972 7567
> > > > Mb: +64 21 536 627
> > > > 87 Spencer Street
> > > > Crofton Downs
> > > > Wellington
> > > > New Zealand
> > > >
> > > > "To the optimist, the glass is half full. To the pessimist, the glass
> > >is
> > > > half empty. To the engineer, the glass is twice as big as it needs to
> > >be."
> > > >
> > > > No animals were harmed in the transmission of this email, although the
> > > > Dog next door is living on borrowed time, let me tell you! Those of
> you
> > > > with an overwhelming fear of the unknown will be gratified to learn
> that
> > > > there is no hidden message revealed by reading this warning backwards.
> > > >
> > > >
> > > >
> > > >
> > > >
> > > > >From: Leroy Hall <leroy@f...>
> > > > >To: basicstamps@yahoogroups.com
> > > > >Subject: Re: [noparse][[/noparse]basicstamps] Any Power Engineers Lurking?
> > > > >Date: Tue, 21 May 2002 5:52 AM
> > > > >
> > > >
> > > > > I think I understand your situation a little better than what was
> > > > > before. I assumed you were using commercial equipment, a mistake on
> my
> > > > > part. Your statement, "I am trying to assess the net effect on the
> > > > > primary side of the coupling transformer, i.e.: as long as the
> > >rectifier
> > > > > is fairly well balanced, there should be no DC reflected back,
> right?"
> > > > > is new to me. I have heard of power reflected in an RF radio type
> > > > > situation, we call it SWR. But I have not heard of DC being
> reflected
> > > > > back across the winding of a x-former. MAybe we could discuss the
> > > > > situation off list. if you like. Sounds interesting at the very
> > > > > least.. I consider myself more a controls engineer, in that I have
> > > > > expertise in PLC.s but power control is also very interesting
> although
> > > > > my experience there is limited more to the theoretical rather than
> the
> > > > > practical side. Good luck..
> > > > >
> > > > > Leroy
> > > > >
> > > > > "Chris Loiacono (E-mail)" wrote:
> > > > >>
> > > > >> I have an AC Phase-angle power controller design that I am trying
> to
> > >fit to
> > > > >> a customer's application.
> > > > >> I mention it here because there are experts here in every field, it
> > >seems,
> > > > >> although the part of it I'm working on is basically an AC Power EE
> > >problem:
> > > > >>
> > > > >> The controller fires gates on SCR/Diode pairs on each leg of a
> three
> > >phase
> > > > >> load. The zero-crossing timing is derived optically from the AC
> line,
> > >and
> > > > >> the command input to the PIC sets the gate delay, or phase angle to
> > >fire at.
> > > > >> It was intended for resistive loads, where the relationship between
> > >voltage
> > > > >> and current is quite simple.
> > > > >>
> > > > >> I need to use it to gate the SCR's into a transformer primary,
> which
> > >is
> > >a
> > > > >> simple 3-wire delta. The secondary is through a three-phase bridge
> > >rectifier
> > > > >> to a wye connected resistive load. You might envision it feeding
> the
> > > > >> resistive equivalent of a 3-phase AC motor stator, but ignore the
> > >concept of
> > > > >> motion.
> > > > >>
> > > > >> I am trying to assess the net effect on the primary side of the
> > >coupling
> > > > >> transformer, ie: as long as the rectifier is fairly well balanced,
> > >there
> > > > >> should be no DC reflected back, right?
> > > > >> Will the current at the transformer primary lag, and will that
> effect
> > >my
> > > > >> zero-cross detect timing, since it is done by LED's? If so, the
> > >controller
> > > > >> will fire past the zero-crossings and make some spectacular
> > >fireworks,
> > >since
> > > > >> it deals with hundreds of Volts at hundreds of Amps.
> > > > >>
> > > > >> Please let me know if anyone has experience with this sort of thing
> > >that
> > > > >> would like to discuss it either on or off-list.
> > > > >>
> > > > >> Chris
> > > > >>
> > > > >> To UNSUBSCRIBE, just send mail to:
> > > > >> basicstamps-unsubscribe@yahoogroups.com
> > > > >> from the same email address that you subscribed. Text in the
> Subject
> > >and
> > > > > Body of the message will be ignored.
> > > > >>
> > > > >>
> > > > >> Your use of Yahoo! Groups is subject to
> > >http://docs.yahoo.com/info/terms/
> > > > >
> > > > > To UNSUBSCRIBE, just send mail to:
> > > > > basicstamps-unsubscribe@yahoogroups.com
> > > > > from the same email address that you subscribed. Text in the
> Subject
> > >and
> > > > > Body of the message will be ignored.
> > > > >
> > > > >
> > > > > Your use of Yahoo! Groups is subject to
> > >http://docs.yahoo.com/info/terms/
> > > > >
> > > > >
> > > >
> > > > To UNSUBSCRIBE, just send mail to:
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> > > > from the same email address that you subscribed. Text in the Subject
> > >and
> > >Body of the message will be ignored.
> > > >
> > > >
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> > > >
> > > >
> > >
> > >
> > >
> > >To UNSUBSCRIBE, just send mail to:
> > > basicstamps-unsubscribe@yahoogroups.com
> > >from the same email address that you subscribed. Text in the Subject and
> > >Body of the message will be ignored.
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> > >Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/
> > >
> > >
> >
> >
> >
> >
> > _________________________________________________________________
> > Meld je aan bij de grootste e-mailservice wereldwijd met MSN Hotmail:
> > http://www.hotmail.com/nl
> >
> >
> > To UNSUBSCRIBE, just send mail to:
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> Body of the message will be ignored.
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> >
>
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The base of the arrow seems to be pin 2, Analog In.
The variable resistor's range is roughly 0-47k ohms. Datasheets pages 7-8
will help you figure out what resistor range to use (the variable resistor
uses the wiper to divide the pot into the pair of "fixed" resistors that is
shown on the datasheet diagram).
Regards,
Daniel
>
Original Message
> From: Don [noparse]/noparse]mailto:[url=http://forums.parallaxinc.com/group/basicstamps/post?postID=4lvPT1mSet2JKnz7cwTREkcsyNKR6Tip1DhuT7XME7OtTnKpYrMhJWOjV2u7uevWmgzkqZsYf-N6BYCBO8ZI1twkg4HTMw]renegade.engineer@v...[/url
> Sent: Thursday, 23 May 2002 12:19
> To: basicstamps@yahoogroups.com
> Subject: Re: [noparse][[/noparse]basicstamps] A to D conversion...
>
>
> Yes, I know about variable resistors, but I'm not sure that
> is the case
> here. Look at
> http://www.lennard.net.nz/electronics/ad.html
> The arrow in question appears to be connected to the A-D
> converter chip, but
> there is no pin identification associated with the IC. If it
> were meant to
> indicate a variable resistor, I would expect the arrow to pass through the
> resistor and not show an apparent physical connection to another
> device. To
> me, the drawing seems to indicate a standard resistor, as it doesn't
> indicate a high-low range for the resistor.
> Don
>
Original Message
> From: "SX-2 commander" <sx2_commander@h...>
> To: <basicstamps@yahoogroups.com>
> Sent: Thursday, May 23, 2002 9:11 AM
> Subject: Re: [noparse][[/noparse]basicstamps] A to D conversion...
>
>
> >
> > An arrow in an resistor means it is a variable resistor. Physical, it is
> > normally the middle pin.
> >
> > >From: "Don" <renegade.engineer@v...>
> > >Reply-To: basicstamps@yahoogroups.com
> > >To: <basicstamps@yahoogroups.com>
> > >Subject: Re: [noparse][[/noparse]basicstamps] A to D conversion...
> > >Date: Thu, 23 May 2002 07:40:42 -0700
> > >
> > > Ben, in the diagram on that link, what is the significance of the
> > >arrow
> > >from the TLC548CP pointing at the 47k resistor?
> > >Don
> > >
Original Message
> > >From: "Ben Lennard" <postmaster@s...>
> > >To: <basicstamps@yahoogroups.com>
> > >Sent: Thursday, May 23, 2002 4:41 AM
> > >Subject: [noparse][[/noparse]basicstamps] A to D conversion...
> > >
> > >
> > > > Hey folks,
> > > >
> > > > Discovered today how easy A to D conversion can be. This
> is going to
> > >help
> > >a
> > > > lot in designing the Data Logger I'm thinking about.
> > > > See the url below for a demo circuit and code. Click on A to D
> > >Converter.
> > > >
> > > > http://www.lennard.net.nz/electronics/electronics.html
> > > >
> > > > cheers,
> > > >
> > > > Ben, Wellington, New Zealand.
> > > >
> > > > --
> > > > http://www.lennard.net.nz/
> > > > Ben Lennard, NCEE, Dip EE
> > > >
> > > > Web Hosting and Electronics R&D
> > > >
> > > > Hm: +64 4 972 7567
> > > > Mb: +64 21 536 627
> > > > 87 Spencer Street
> > > > Crofton Downs
> > > > Wellington
> > > > New Zealand
> > > >
> > > > "To the optimist, the glass is half full. To the
> pessimist, the glass
> > >is
> > > > half empty. To the engineer, the glass is twice as big as
> it needs to
> > >be."
> > > >
> > > > No animals were harmed in the transmission of this email,
> although the
> > > > Dog next door is living on borrowed time, let me tell you! Those of
> you
> > > > with an overwhelming fear of the unknown will be gratified to learn
> that
> > > > there is no hidden message revealed by reading this warning
> backwards.
> > > >
> > > >
> > > >
> > > >
> > > >
> > > > >From: Leroy Hall <leroy@f...>
> > > > >To: basicstamps@yahoogroups.com
> > > > >Subject: Re: [noparse][[/noparse]basicstamps] Any Power Engineers Lurking?
> > > > >Date: Tue, 21 May 2002 5:52 AM
> > > > >
> > > >
> > > > > I think I understand your situation a little better than what was
> > > > > before. I assumed you were using commercial equipment, a
> mistake on
> my
> > > > > part. Your statement, "I am trying to assess the net
> effect on the
> > > > > primary side of the coupling transformer, i.e.: as long as the
> > >rectifier
> > > > > is fairly well balanced, there should be no DC reflected back,
> right?"
> > > > > is new to me. I have heard of power reflected in an RF radio type
> > > > > situation, we call it SWR. But I have not heard of DC being
> reflected
> > > > > back across the winding of a x-former. MAybe we could
> discuss the
> > > > > situation off list. if you like. Sounds interesting at the very
> > > > > least.. I consider myself more a controls engineer, in
> that I have
> > > > > expertise in PLC.s but power control is also very interesting
> although
> > > > > my experience there is limited more to the theoretical rather than
> the
> > > > > practical side. Good luck..
> > > > >
> > > > > Leroy
> > > > >
> > > > > "Chris Loiacono (E-mail)" wrote:
> > > > >>
> > > > >> I have an AC Phase-angle power controller design that I am trying
> to
> > >fit to
> > > > >> a customer's application.
> > > > >> I mention it here because there are experts here in
> every field, it
> > >seems,
> > > > >> although the part of it I'm working on is basically an
> AC Power EE
> > >problem:
> > > > >>
> > > > >> The controller fires gates on SCR/Diode pairs on each leg of a
> three
> > >phase
> > > > >> load. The zero-crossing timing is derived optically from the AC
> line,
> > >and
> > > > >> the command input to the PIC sets the gate delay, or
> phase angle to
> > >fire at.
> > > > >> It was intended for resistive loads, where the
> relationship between
> > >voltage
> > > > >> and current is quite simple.
> > > > >>
> > > > >> I need to use it to gate the SCR's into a transformer primary,
> which
> > >is
> > >a
> > > > >> simple 3-wire delta. The secondary is through a
> three-phase bridge
> > >rectifier
> > > > >> to a wye connected resistive load. You might envision it feeding
> the
> > > > >> resistive equivalent of a 3-phase AC motor stator, but ignore the
> > >concept of
> > > > >> motion.
> > > > >>
> > > > >> I am trying to assess the net effect on the primary side of the
> > >coupling
> > > > >> transformer, ie: as long as the rectifier is fairly well
> balanced,
> > >there
> > > > >> should be no DC reflected back, right?
> > > > >> Will the current at the transformer primary lag, and will that
> effect
> > >my
> > > > >> zero-cross detect timing, since it is done by LED's? If so, the
> > >controller
> > > > >> will fire past the zero-crossings and make some spectacular
> > >fireworks,
> > >since
> > > > >> it deals with hundreds of Volts at hundreds of Amps.
> > > > >>
> > > > >> Please let me know if anyone has experience with this
> sort of thing
> > >that
> > > > >> would like to discuss it either on or off-list.
> > > > >>
> > > > >> Chris
> > > > >>
> > > > >> To UNSUBSCRIBE, just send mail to:
> > > > >> basicstamps-unsubscribe@yahoogroups.com
> > > > >> from the same email address that you subscribed. Text in the
> Subject
> > >and
> > > > > Body of the message will be ignored.
> > > > >>
> > > > >>
> > > > >> Your use of Yahoo! Groups is subject to
> > >http://docs.yahoo.com/info/terms/
> > > > >
> > > > > To UNSUBSCRIBE, just send mail to:
> > > > > basicstamps-unsubscribe@yahoogroups.com
> > > > > from the same email address that you subscribed. Text in the
> Subject
> > >and
> > > > > Body of the message will be ignored.
> > > > >
> > > > >
> > > > > Your use of Yahoo! Groups is subject to
> > >http://docs.yahoo.com/info/terms/
> > > > >
> > > > >
> > > >
> > > > To UNSUBSCRIBE, just send mail to:
> > > > basicstamps-unsubscribe@yahoogroups.com
> > > > from the same email address that you subscribed. Text in
> the Subject
> > >and
> > >Body of the message will be ignored.
> > > >
> > > >
> > > > Your use of Yahoo! Groups is subject to
> > >http://docs.yahoo.com/info/terms/
> > > >
> > > >
> > > >
> > >
> > >
> > >
> > >To UNSUBSCRIBE, just send mail to:
> > > basicstamps-unsubscribe@yahoogroups.com
> > >from the same email address that you subscribed. Text in the
> Subject and
> > >Body of the message will be ignored.
> > >
> > >
> > >Your use of Yahoo! Groups is subject to
http://docs.yahoo.com/info/terms/
> >
> >
>
>
>
>
> _________________________________________________________________
> Meld je aan bij de grootste e-mailservice wereldwijd met MSN Hotmail:
> http://www.hotmail.com/nl
>
>
> To UNSUBSCRIBE, just send mail to:
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> from the same email address that you subscribed. Text in the Subject and
Body of the message will be ignored.
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>
>
To UNSUBSCRIBE, just send mail to:
basicstamps-unsubscribe@yahoogroups.com
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Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/
wiper.
The line from the IC is it's Analogue input (pin 2).
--
http://www.lennard.net.nz/
Ben Lennard, NCEE, Dip EE
Web Hosting and Electronics R&D
Hm: +64 4 972 7567
Mb: +64 21 536 627
87 Spencer Street
Crofton Downs
Wellington
New Zealand
"To the optimist, the glass is half full. To the pessimist, the glass is
half empty. To the engineer, the glass is twice as big as it needs to be."
No animals were harmed in the transmission of this email, although the
Dog next door is living on borrowed time, let me tell you! Those of you
with an overwhelming fear of the unknown will be gratified to learn that
there is no hidden message revealed by reading this warning backwards.
>From: "Don" <renegade.engineer@v...>
>To: <basicstamps@yahoogroups.com>
>Subject: Re: [noparse][[/noparse]basicstamps] A to D conversion...
>Date: Fri, 24 May 2002 2:40 AM
>
> Ben, in the diagram on that link, what is the significance of the arrow
> from the TLC548CP pointing at the 47k resistor?
> Don
>
Original Message
> From: "Ben Lennard" <postmaster@s...>
> To: <basicstamps@yahoogroups.com>
> Sent: Thursday, May 23, 2002 4:41 AM
> Subject: [noparse][[/noparse]basicstamps] A to D conversion...
>
>
>> Hey folks,
>>
>> Discovered today how easy A to D conversion can be. This is going to help
> a
>> lot in designing the Data Logger I'm thinking about.
>> See the url below for a demo circuit and code. Click on A to D Converter.
>>
>> http://www.lennard.net.nz/electronics/electronics.html
>>
>> cheers,
>>
>> Ben, Wellington, New Zealand.
>>
>> --
>> http://www.lennard.net.nz/
>> Ben Lennard, NCEE, Dip EE
>>
>> Web Hosting and Electronics R&D
>>
>> Hm: +64 4 972 7567
>> Mb: +64 21 536 627
>> 87 Spencer Street
>> Crofton Downs
>> Wellington
>> New Zealand
>>
>> "To the optimist, the glass is half full. To the pessimist, the glass is
>> half empty. To the engineer, the glass is twice as big as it needs to
> be."
>>
>> No animals were harmed in the transmission of this email, although the
>> Dog next door is living on borrowed time, let me tell you! Those of you
>> with an overwhelming fear of the unknown will be gratified to learn that
>> there is no hidden message revealed by reading this warning backwards.
>>
>>
>>
>>
>>
>> >From: Leroy Hall <leroy@f...>
>> >To: basicstamps@yahoogroups.com
>> >Subject: Re: [noparse][[/noparse]basicstamps] Any Power Engineers Lurking?
>> >Date: Tue, 21 May 2002 5:52 AM
>> >
>>
>> > I think I understand your situation a little better than what was
>> > before. I assumed you were using commercial equipment, a mistake on my
>> > part. Your statement, "I am trying to assess the net effect on the
>> > primary side of the coupling transformer, i.e.: as long as the rectifier
>> > is fairly well balanced, there should be no DC reflected back, right?"
>> > is new to me. I have heard of power reflected in an RF radio type
>> > situation, we call it SWR. But I have not heard of DC being reflected
>> > back across the winding of a x-former. MAybe we could discuss the
>> > situation off list. if you like. Sounds interesting at the very
>> > least.. I consider myself more a controls engineer, in that I have
>> > expertise in PLC.s but power control is also very interesting although
>> > my experience there is limited more to the theoretical rather than the
>> > practical side. Good luck..
>> >
>> > Leroy
>> >
>> > "Chris Loiacono (E-mail)" wrote:
>> >>
>> >> I have an AC Phase-angle power controller design that I am trying to
> fit to
>> >> a customer's application.
>> >> I mention it here because there are experts here in every field, it
> seems,
>> >> although the part of it I'm working on is basically an AC Power EE
> problem:
>> >>
>> >> The controller fires gates on SCR/Diode pairs on each leg of a three
> phase
>> >> load. The zero-crossing timing is derived optically from the AC line,
> and
>> >> the command input to the PIC sets the gate delay, or phase angle to
> fire at.
>> >> It was intended for resistive loads, where the relationship between
> voltage
>> >> and current is quite simple.
>> >>
>> >> I need to use it to gate the SCR's into a transformer primary, which is
> a
>> >> simple 3-wire delta. The secondary is through a three-phase bridge
> rectifier
>> >> to a wye connected resistive load. You might envision it feeding the
>> >> resistive equivalent of a 3-phase AC motor stator, but ignore the
> concept of
>> >> motion.
>> >>
>> >> I am trying to assess the net effect on the primary side of the
> coupling
>> >> transformer, ie: as long as the rectifier is fairly well balanced,
> there
>> >> should be no DC reflected back, right?
>> >> Will the current at the transformer primary lag, and will that effect
> my
>> >> zero-cross detect timing, since it is done by LED's? If so, the
> controller
>> >> will fire past the zero-crossings and make some spectacular fireworks,
> since
>> >> it deals with hundreds of Volts at hundreds of Amps.
>> >>
>> >> Please let me know if anyone has experience with this sort of thing
> that
>> >> would like to discuss it either on or off-list.
>> >>
>> >> Chris
>> >>
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>
>
>
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>
> Yes, I know about variable resistors, but I'm not sure that is the case
> here. Look at
> http://www.lennard.net.nz/electronics/ad.html
From the verbage in the descritption and the looks of the diagram, it is
the wiper of the 47k pot connected to the input pin of the adc. Proper
schematic icon for a pot; not really but it does get the point across
IMHO.
Take Care,
--
Dale Harwood [noparse][[/noparse] N4VFF ]
internet> dale@h...
ax.25> n4vff@n4vff.#cha.tn.usa.noam
#include <std_disclaimer.h>