GB731523A - Improvements in or relating to variable electrical resistances - Google Patents
Improvements in or relating to variable electrical resistancesInfo
- Publication number
- GB731523A GB731523A GB2449850A GB2449850A GB731523A GB 731523 A GB731523 A GB 731523A GB 2449850 A GB2449850 A GB 2449850A GB 2449850 A GB2449850 A GB 2449850A GB 731523 A GB731523 A GB 731523A
- Authority
- GB
- United Kingdom
- Prior art keywords
- resistance
- conductance
- conductances
- decade
- terminals
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired
Links
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R1/00—Details of instruments or arrangements of the types included in groups G01R5/00 - G01R13/00 and G01R31/00
- G01R1/20—Modifications of basic electric elements for use in electric measuring instruments; Structural combinations of such elements with such instruments
- G01R1/203—Resistors used for electric measuring, e.g. decade resistors standards, resistors for comparators, series resistors, shunts
Landscapes
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Measurement Of Resistance Or Impedance (AREA)
Abstract
731,523. Measuring temperature; variable resistance and conductance networks; electric analogue calculating systems. SANGAMO WESTON, Ltd. July 5. 1951 [Oct. 6, 1950], No. 24498/50. Class 37. [Also in Group XXXVIII] .Relates to resistance and conductance networks adjustable in steps so as to simulate a non-linear law of the type Rt=Ro (1+-at-bt<2>) between a variable t and the 'resistance R. The invention is based or derived in accordance with the principle that the resistance/temperature curve of a resistance whose value varies uniformly with temperature t shunted by a resistance of constant value approximates to the required curve. According to a first aspect (Figs. 1 and 2), the invention provides a resistance network comprising two terminals (T1, T2) and two resistances (R1-R3) and (R4) connected in parallel with respect to said terminals and at least two control means (e.g. switches S3 and S4) calibrated respectively in terms of a different unit of said variable for varying a first one of said resistances (R3) in linear manner and at least one of said calibrated control means (S4) simultaneously varying the second one of said resistances (R4) in a non- linear manner. In Fig. 2 the switch S3 controlling the R3 or hundreds decade is ganged to switch S4 of step shunt resistor R4 so that a different value of shunt is switched in across the series three-decade combination R3, R2, R1 at each adjustment position of switch S3. Fig. 2 is calibrated for measurements from - 100‹ to +500‹ C. The negative values are measured by setting S3, S4 on the negative step (shown ringed) corresponding to - 100‹ C. and in effect operating S1, S2 in reverse against negative indices shown individually ringed in Fig. 1, e.g. - 100‹ C. is given by the S3 setting on the ringed negative in R3 with S2 at - 90‹ C. (or zero on the positive range) in R2 and S1 at - 10‹ C..(or zero on the positive range) in R1. According to a second aspect the invention provides a resistance or conductance network comprising two terminals (T1, T2), Fig. 3, two resistances or conductances (X and Y-X) connected between said terminals such that the resistance (R) or conductance between the said terminals is expressible in the form X(Y - X)/Y and calibrated control means (S1 and S2) for varying in a non-linear manner the total resistance or conductance in the manner that the resistance or conductance X is varied in a linear manner whilst maintaining constant the total resistance or conductance Y. In Fig. 4 the closed loop Y is translated into series resistors R4-R8 with R4, R5 in 10‹ and 100‹ C. steps respectively. The X100 switch S2 may be connected to junction x between R7/R8 with x chosen such that R7=R6 minus the total resistance of R4 so as to provide a - 100‹ C. setting. A further arrangement, Fig. 5, has the closed loop Y comprising decade boxes B1, B2 with similar denominations coupled so that B1 adds/subtracts as B2 subtracts/adds respectively and in equal increments. In Fig. 6, B is a decade resistance as described above and at bridge balance B indicates directly the temperature of the platinum resistance thermometer Rt. Fig. 7 is a conversion into conductances with B now C (conductance) in an opposite arm and using conductances it is shown that at balance (see Fig. 8) Rt=X(Y - X)/Y, where Rt represents a platinum resistance thermometer and conductance arm C comprises conductances X/K and Y-X/K in series (K=PQ). Conductances are switched in parallel for addition and to maintain Y constant while X varies a conductance is switched from shunting X to shunting Y-X. This is demonstrated in Fig. 9 wherein biriary-counting relays operate on change-over switches RS1-RS7 so that C1- C7 shunt Cx or Cy. Figs. 10 and 11 (not shown), illustrate decade-conductance networks with the total conductance Y held constant by step or bar switching controlling the required conductances. The invention is fully developed and explained mathematically throughout the Specification. The arrangements disclosed may be employed in a multi-range bridge type temperature indicator or recorder wherein the lowest step resistance or conductance comprises a motor-driven self-balance slide wire. Further temperature measuring applications consist in controlling the switches by a stepping mechanism provided with a cyclometer dial indicator or coupling the switches to printing heads for chart printing in time sequence.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
GB2449850A GB731523A (en) | 1950-10-06 | 1950-10-06 | Improvements in or relating to variable electrical resistances |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
GB2449850A GB731523A (en) | 1950-10-06 | 1950-10-06 | Improvements in or relating to variable electrical resistances |
Publications (1)
Publication Number | Publication Date |
---|---|
GB731523A true GB731523A (en) | 1955-06-08 |
Family
ID=10212596
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
GB2449850A Expired GB731523A (en) | 1950-10-06 | 1950-10-06 | Improvements in or relating to variable electrical resistances |
Country Status (1)
Country | Link |
---|---|
GB (1) | GB731523A (en) |
Cited By (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
EP3786599A1 (en) * | 2019-09-02 | 2021-03-03 | ContiTech Schlauch GmbH | Measuring device for detecting temperature-dependent resistance changes and hose system comprising such a measuring device |
CN113470489A (en) * | 2021-05-21 | 2021-10-01 | 淮北师范大学信息学院 | Network type bridge resistance measurement experiment instrument and operation method |
-
1950
- 1950-10-06 GB GB2449850A patent/GB731523A/en not_active Expired
Cited By (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
EP3786599A1 (en) * | 2019-09-02 | 2021-03-03 | ContiTech Schlauch GmbH | Measuring device for detecting temperature-dependent resistance changes and hose system comprising such a measuring device |
CN113470489A (en) * | 2021-05-21 | 2021-10-01 | 淮北师范大学信息学院 | Network type bridge resistance measurement experiment instrument and operation method |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
US2707880A (en) | Relative humidity measuring apparatus | |
US2951200A (en) | Calibration indicator | |
US3284709A (en) | Precision voltmeter using selectable series connected, digitally related resistors which are calibrated to read the value of input signal | |
US4433287A (en) | Range switching device for electric meter | |
GB731523A (en) | Improvements in or relating to variable electrical resistances | |
US3252080A (en) | Digitally adjustable attenuator | |
US3287978A (en) | Electrical bridge circuit | |
US2759150A (en) | Circuit and method for producing standard voltages | |
US3443215A (en) | Impedance measuring bridge with voltage divider providing constant source impedance to bridge | |
US2881392A (en) | D. c. voltage ratio measuring system | |
US2925554A (en) | Resistance checker | |
US4157494A (en) | Controlled multidigit resistance box | |
US3390329A (en) | Simplified apparatus for measuring primary electrical quantities | |
US3320526A (en) | Low impedance measuring apparatus including a pair of multiple terminal networks and a voltage divider | |
US2144216A (en) | Educational apparatus | |
Hirayama et al. | 10-kV high-Accuracy dc voltage divider | |
US1954311A (en) | Electric meter | |
US2854643A (en) | Attenuators | |
US3461383A (en) | Resistance measuring method and apparatus having means for alternately connecting unknown resistor to different arms of bridge | |
US3940686A (en) | Linear output bridge circuit | |
US2162894A (en) | Method and apparatus for measuring nonlinear impedances | |
US3021495A (en) | Ratio-measuring circuit | |
US2677102A (en) | Transfer conductance test set | |
US2993377A (en) | Direct reading resistance thermometer | |
US3292081A (en) | Apparatus for measuring the negative ratio of voltage |