Re: [volt-nuts] Ayrton Shunt does double duty.
https://nvlpubs.nist.gov/nistpubs/Legacy/SP/nbsspecialpublication300v3.pdf has a few articles on potentiometers and volt boxes. F.K. Harris's Electrical measurements (1952) has further information. Bruce > On 05 May 2018 at 09:36 Bruce Griffiths wrote: > > > The volt box is likely to be a voltage divider that was used to divide a > voltage to be measured down to a value within the measurement range of a L & > N potentiometer (not the 3 terminal component but the type that sets up the > current in a series string of resistors to a known vale by comparing the > voltage across a subset with the voltage of a standard cell. The unknown > voltage can then be measured by comparing it against the voltage drop across > a adjustable subset of the series resistor string). > They are mentioned in various NBS (NIST) publications of the era as well as > in various texts on dc electrical measurements. They were in common use up > till around the 1980's. > > Bruce > > On 05 May 2018 at 01:55 geoelectron...@rallstech.net wrote: > > > > > > Hello Dave. > > > > So far I have identified 3 different Leeds & Northrup "Boxes". > > Originally my intention was to re-purpose the box, panel connectors and > > switch for a project to make my own precision resistor banks. > > > > All use different switches and vastly different resistors to achieve > > their original purpose. > > > > The subject of the first one is the "Ayrton (wired) Shunt Box". It was > > used with a galvanometer as a sort of attenuator (current divider), > > uniquely wired in the Ayrton fashion to insure the galvanometer was > > always connected to a shunt resistor, even during switching. Think of > > the scheme as a stepped potentiometer, the meter was between the two > > extremes, while the source went to the wiper. Just backwards from a > > Voltage divider. > > > > Next is the "Shunt Box". It's resistors are copper straps, the lowest > > value is made from a copper sheet maybe 5 inches wide, bent into a > > corrugated shape to fit inside the box. Remarkable construction, should > > be quite stable as a milliOhm standard. > > > > The last one is called "Volt Box". Its resistors are wire wound on > > ceramic forms, obviously with great care. The switch is protected and > > possibly gold plated contacts. Multiple series connected resistors are > > used to provide the correct values plus spread the current (heat load) > > around, and they are spaced far apart and with air space around each > > one. So far no clue as to its original function but of course I have > > traced the schematic. > > > > Very little is freely available on the 'net about them nor a period > > catalog so far. > > > > George Dowell > > ___ > > volt-nuts mailing list -- volt-nuts@febo.com > > To unsubscribe, go to > > https://www.febo.com/cgi-bin/mailman/listinfo/volt-nuts > > and follow the instructions there. > ___ > volt-nuts mailing list -- volt-nuts@febo.com > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/volt-nuts > and follow the instructions there. ___ volt-nuts mailing list -- volt-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/volt-nuts and follow the instructions there.
Re: [volt-nuts] Ayrton Shunt does double duty.
The volt box is likely to be a voltage divider that was used to divide a voltage to be measured down to a value within the measurement range of a L & N potentiometer (not the 3 terminal component but the type that sets up the current in a series string of resistors to a known vale by comparing the voltage across a subset with the voltage of a standard cell. The unknown voltage can then be measured by comparing it against the voltage drop across a adjustable subset of the series resistor string). They are mentioned in various NBS (NIST) publications of the era as well as in various texts on dc electrical measurements. They were in common use up till around the 1980's. Bruce > On 05 May 2018 at 01:55 geoelectron...@rallstech.net wrote: > > > Hello Dave. > > So far I have identified 3 different Leeds & Northrup "Boxes". > Originally my intention was to re-purpose the box, panel connectors and > switch for a project to make my own precision resistor banks. > > All use different switches and vastly different resistors to achieve > their original purpose. > > The subject of the first one is the "Ayrton (wired) Shunt Box". It was > used with a galvanometer as a sort of attenuator (current divider), > uniquely wired in the Ayrton fashion to insure the galvanometer was > always connected to a shunt resistor, even during switching. Think of > the scheme as a stepped potentiometer, the meter was between the two > extremes, while the source went to the wiper. Just backwards from a > Voltage divider. > > Next is the "Shunt Box". It's resistors are copper straps, the lowest > value is made from a copper sheet maybe 5 inches wide, bent into a > corrugated shape to fit inside the box. Remarkable construction, should > be quite stable as a milliOhm standard. > > The last one is called "Volt Box". Its resistors are wire wound on > ceramic forms, obviously with great care. The switch is protected and > possibly gold plated contacts. Multiple series connected resistors are > used to provide the correct values plus spread the current (heat load) > around, and they are spaced far apart and with air space around each > one. So far no clue as to its original function but of course I have > traced the schematic. > > Very little is freely available on the 'net about them nor a period > catalog so far. > > George Dowell > ___ > volt-nuts mailing list -- volt-nuts@febo.com > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/volt-nuts > and follow the instructions there. ___ volt-nuts mailing list -- volt-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/volt-nuts and follow the instructions there.
Re: [volt-nuts] Ayrton Shunt does double duty.
Hello Dave. So far I have identified 3 different Leeds & Northrup "Boxes". Originally my intention was to re-purpose the box, panel connectors and switch for a project to make my own precision resistor banks. All use different switches and vastly different resistors to achieve their original purpose. The subject of the first one is the "Ayrton (wired) Shunt Box". It was used with a galvanometer as a sort of attenuator (current divider), uniquely wired in the Ayrton fashion to insure the galvanometer was always connected to a shunt resistor, even during switching. Think of the scheme as a stepped potentiometer, the meter was between the two extremes, while the source went to the wiper. Just backwards from a Voltage divider. Next is the "Shunt Box". It's resistors are copper straps, the lowest value is made from a copper sheet maybe 5 inches wide, bent into a corrugated shape to fit inside the box. Remarkable construction, should be quite stable as a milliOhm standard. The last one is called "Volt Box". Its resistors are wire wound on ceramic forms, obviously with great care. The switch is protected and possibly gold plated contacts. Multiple series connected resistors are used to provide the correct values plus spread the current (heat load) around, and they are spaced far apart and with air space around each one. So far no clue as to its original function but of course I have traced the schematic. Very little is freely available on the 'net about them nor a period catalog so far. George Dowell ___ volt-nuts mailing list -- volt-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/volt-nuts and follow the instructions there.
Re: [volt-nuts] Ayrton Shunt does double duty.
On Mon, 30 Apr 2018, 20:02 , wrote: > Leeds and Northrup Ayrton Shunt box Model 2664. > > Modified to do double duty as a precision resistor standard. I must admit I don't know what the purpose of the original unit is. Perhaps as part of a bridge given the galvanometer connections. I know when I was looking to check out my HP 4284A precession LCR meter (basic uncertainty of 0.05%) I was able to buy some 0.005% resistors in some values. I think if trying to build a precision resistance box I would look for resistors better than the 0.03% in there. I wonder if you could go to much lower resistance values if you used the galvanometer connections as sense wires. But maybe you are using it in a way I don't understand. I only have my mobile phone now, so are not going to search the web for more information. Dave. ___ volt-nuts mailing list -- volt-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/volt-nuts and follow the instructions there.
Re: [volt-nuts] Ayrton Shunt does double duty.
First class work there Mitch. Did I see a ham radio? 73 DE K0FF George Dowell On 2018/04/30 09:19 PM, Mitch Van Ochten wrote: > Built a small temperature chamber using a Starbucks Refrigerator, Yokogawa > Temperature controller, and PTC Heater (300 watt). It covers 0 degrees C to > 55 degrees C and has an RS-485 interface to the PC. The compressor runs all > the time, and the controller cycles the 300 watt heater as needed to > stabilize the temperature. Here is a link to a YouTube video showing it: > > https://youtu.be/ETj4owB3I0k > > Mitch > > -Original Message- > From: volt-nuts [mailto:volt-nuts-boun...@febo.com] On Behalf Of > geoelectron...@rallstech.net > Sent: Monday, April 30, 2018 6:22 PM > To: Discussion of precise voltage measurement > Subject: Re: [volt-nuts] Ayrton Shunt does double duty. > > No environmental chamber yet, have a Yokogawa controller and and an EIS > sensor simulator, going with a small box in the first for individual > components, but workload keeping me from completion of so many fun > projects. Now we are nearing grass cutting season here, the completion > of projects ratio will suffer. > > George Dowell > > On 2018/04/30 03:11 PM, jasonpe...@gmail.com wrote: > > Much appreciated! I saw some of those units listed on eBay inexpensively and > was curious about such a "mod". Have you characterized it for tempco? > > Sent from my iPhone > > On Apr 30, 2018, at 2:02 PM, geoelectron...@rallstech.net wrote: > > Leeds and Northrup Ayrton Shunt box Model 2664. > > Modified to do double duty as a precision resistor standard. > > Pictures here: > > http://www.qsl.net/k/k0ff/VOLT_NUTS/Ayrton_Shunt_Conversion/ > > Later I'll write it up and post it to that link as a PDF with text and > pictures, plus any subsequent modifications. > > George Dowell > ___ > volt-nuts mailing list -- volt-nuts@febo.com > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/volt-nuts > and follow the instructions there. > ___ > volt-nuts mailing list -- volt-nuts@febo.com > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/volt-nuts > and follow the instructions there. ___ volt-nuts mailing list -- volt-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/volt-nuts and follow the instructions there. ___ volt-nuts mailing list -- volt-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/volt-nuts and follow the instructions there. ___ volt-nuts mailing list -- volt-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/volt-nuts and follow the instructions there.
Re: [volt-nuts] Ayrton Shunt does double duty.
Built a small temperature chamber using a Starbucks Refrigerator, Yokogawa Temperature controller, and PTC Heater (300 watt). It covers 0 degrees C to 55 degrees C and has an RS-485 interface to the PC. The compressor runs all the time, and the controller cycles the 300 watt heater as needed to stabilize the temperature. Here is a link to a YouTube video showing it: https://youtu.be/ETj4owB3I0k Mitch -Original Message- From: volt-nuts [mailto:volt-nuts-boun...@febo.com] On Behalf Of geoelectron...@rallstech.net Sent: Monday, April 30, 2018 6:22 PM To: Discussion of precise voltage measurement Subject: Re: [volt-nuts] Ayrton Shunt does double duty. No environmental chamber yet, have a Yokogawa controller and and an EIS sensor simulator, going with a small box in the first for individual components, but workload keeping me from completion of so many fun projects. Now we are nearing grass cutting season here, the completion of projects ratio will suffer. George Dowell On 2018/04/30 03:11 PM, jasonpe...@gmail.com wrote: > Much appreciated! I saw some of those units listed on eBay inexpensively and > was curious about such a "mod". Have you characterized it for tempco? > > Sent from my iPhone > >> On Apr 30, 2018, at 2:02 PM, geoelectron...@rallstech.net wrote: >> >> Leeds and Northrup Ayrton Shunt box Model 2664. >> >> Modified to do double duty as a precision resistor standard. >> >> Pictures here: >> >> http://www.qsl.net/k/k0ff/VOLT_NUTS/Ayrton_Shunt_Conversion/ >> >> Later I'll write it up and post it to that link as a PDF with text and >> pictures, plus any subsequent modifications. >> >> George Dowell >> ___ >> volt-nuts mailing list -- volt-nuts@febo.com >> To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/volt-nuts >> and follow the instructions there. > ___ > volt-nuts mailing list -- volt-nuts@febo.com > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/volt-nuts > and follow the instructions there. ___ volt-nuts mailing list -- volt-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/volt-nuts and follow the instructions there. ___ volt-nuts mailing list -- volt-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/volt-nuts and follow the instructions there.
Re: [volt-nuts] Ayrton Shunt does double duty.
No environmental chamber yet, have a Yokogawa controller and and an EIS sensor simulator, going with a small box in the first for individual components, but workload keeping me from completion of so many fun projects. Now we are nearing grass cutting season here, the completion of projects ratio will suffer. George Dowell On 2018/04/30 03:11 PM, jasonpe...@gmail.com wrote: > Much appreciated! I saw some of those units listed on eBay inexpensively and > was curious about such a "mod". Have you characterized it for tempco? > > Sent from my iPhone > >> On Apr 30, 2018, at 2:02 PM, geoelectron...@rallstech.net wrote: >> >> Leeds and Northrup Ayrton Shunt box Model 2664. >> >> Modified to do double duty as a precision resistor standard. >> >> Pictures here: >> >> http://www.qsl.net/k/k0ff/VOLT_NUTS/Ayrton_Shunt_Conversion/ >> >> Later I'll write it up and post it to that link as a PDF with text and >> pictures, plus any subsequent modifications. >> >> George Dowell >> ___ >> volt-nuts mailing list -- volt-nuts@febo.com >> To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/volt-nuts >> and follow the instructions there. > ___ > volt-nuts mailing list -- volt-nuts@febo.com > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/volt-nuts > and follow the instructions there. ___ volt-nuts mailing list -- volt-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/volt-nuts and follow the instructions there.
Re: [volt-nuts] Ayrton Shunt does double duty.
Much appreciated! I saw some of those units listed on eBay inexpensively and was curious about such a “mod”. Have you characterized it for tempco? Sent from my iPhone > On Apr 30, 2018, at 2:02 PM, geoelectron...@rallstech.net wrote: > > Leeds and Northrup Ayrton Shunt box Model 2664. > > Modified to do double duty as a precision resistor standard. > > Pictures here: > > http://www.qsl.net/k/k0ff/VOLT_NUTS/Ayrton_Shunt_Conversion/ > > Later I'll write it up and post it to that link as a PDF with text and > pictures, plus any subsequent modifications. > > George Dowell > ___ > volt-nuts mailing list -- volt-nuts@febo.com > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/volt-nuts > and follow the instructions there. ___ volt-nuts mailing list -- volt-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/volt-nuts and follow the instructions there.
[volt-nuts] Ayrton Shunt does double duty.
Leeds and Northrup Ayrton Shunt box Model 2664. Modified to do double duty as a precision resistor standard. Pictures here: http://www.qsl.net/k/k0ff/VOLT_NUTS/Ayrton_Shunt_Conversion/ Later I'll write it up and post it to that link as a PDF with text and pictures, plus any subsequent modifications. George Dowell ___ volt-nuts mailing list -- volt-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/volt-nuts and follow the instructions there.
