GB/T 14913-1994 DC digital voltmeter and DC analog-to-digital converter
Some standard content:
UDC621.317.713-621.314.1
National Standard of the People's Republic of China
GB/T 14913 94
DC digital voltmeters and DC analog-to-digital convertersDigital electronic d, c. voltmeters and d. c, electronicanalogue-to-digital convertors1994-01-11Published
National Supervision and Technical Supervision Bureau
1994-10-01Implementation
National Standard of the People's Republic of China
DC digital voltmeters and DC analog-to-digital convertersDiglial electraaic d, e, vullmelers and d. r,elertravicanalogue-to-digital This standard refers to E/T 48 DC voltmeter and DC analog-to-digital converter (1574 edition): 1 Subject content and scope of application (B/T 14913-94) This standard specifies the technical specifications, technical requirements, test methods and frequency planning of DC digital voltmeters and DC analog-to-digital converters, as well as the packaging, transportation, storage, etc. This standard is applicable to digital DC voltage measuring instruments (hereinafter referred to as instruments) and analog-to-digital converters (hereinafter referred to as converters) in data and information processing equipment or systems for converting DC current. This standard is also applicable to the DC and voltage measurement functions of digital multimeters and the components used in conjunction with the measuring instruments. If the measuring instruments and accessories are calibrated together, this standard is also applicable to their combination. Some parts of this standard can be applied to other types of DC/DC converters, such as digital multimeters. Original meter, DC digital ammeter. This standard is not used for instruments to measure or transform AC voltage. 2 Lead standard
GR1: Also installed and transported with the diagram
G24 Electric production test specification
GB4793 Safety requirements for electric instruments GB6567.1 General outline for environmental testing of electronic measuring instruments B6587.3 Temperature test of measuring instruments under low temperature
GB6587. Electronic measuring instrument degradation test
GB6587.4 Electronic measuring instrument vibration test
GB65R7.6 Electronic measuring instrument operation test GB6557. Neutron measuring instrument electrostatic test GB6512 Interpretation of the relevant provisions of the measuring instrument H659 Electronic measuring instrument quantity inspection plan
3 Terminology
3.1 Terminology
3.1.1 Electrical signal
A sum of several parameters. Note: This standard is a signal that contains information. 3.1.2 Telecommunication information signal State Technical Supervision Bureau 1994-1-11 approved 9941001 implementation bottle
Detailed information transmission electrical signal effect.
CB/T14913-94
3.1.3 Physical simulation selling displayane.oguerepresetetiorolaphicalquat:tityUse one or more physical display: In the table, the real combustion case changes in the interval, and the quantity can be continuously collected in the corresponding time.
31.4 Physical digital representation digtalpreat:1aifphialquati in the specified range of your case physical quantity using medical numbers, mathematical signals to represent the combination of the two. 3.1.5 Simulated signal annloguc#signal
Parameters in one or more ranges are called signals that change continuously, and different compensation numbers should be different in the plan. The basic information of the digital signal is the range of the parameter value, and each range corresponds to the information of the company. The effective word of a disk is the effective word.
3.1.7 Code qugn:zior
This process also divides the goods into a finite number of clear Han intervals, which are expressed by a fixed value or * in the medical interval. For example, the age of a person can be expressed as a villa in the away game. 3.1.7.1 Ratio unit quiwnimuit
Nominal equal width positive subinterval width,
Note: The units in each book are not equal, which is particularly challenging. 3. 1.8 Code nde
The drug manufacturer's "clear regulations, which stipulates the use of a set of recommended numbers in the data specification method: 3.1,9 abbreviated code cnrodetta)
The code is reverse transformed.
: The general 1 in the teaching code is "this\total" with "F" and other forms. The English/English code also adopts two's complement code and H(I) code, etc. 3.1.1 Decimal element (binary digit, special) binaryelemert (binalydiuirlin) The digital signal is represented by a group of state elements, and these state elements are realized by the digital signal rate. The meaning of each state is determined by the system code, and the time (or space) position of the signal is used to indicate that each state element can be composed of "1" or logic "+", which corresponds to the "1" level state or "+" state of the signal. These are all called binary elements, which are used to indicate the bit change. 3.1.11 Characters are used to convey information in a group of components, or to arrange them in a recognized format (ordered order), or more commonly, in a group of components. 3.1.12 Ordinal characters are used to represent the components of a string (or binary string) in a recognized format. Note, because 1 said "three pairs", "words\, one non-pharmaceutical word\ and out of the application of the method of holding the heart, 3..13 Meng / scattered transform nlogurt2igita]conversian use the method of picking, transformation, leakage code and necessary auxiliary operations to transform the analog voltage into a mathematical quantity. 3.\,14 positive / x transform with electroninannlague-lr-tigiil>avrn the electric signal into analog-to-digital conversion and express it in digital form. 3.1.15 unexpectedly taught half-horse voltage attenuation igisalelecrorscvolmete each potential / digital converter can be used to measure the electronic value in digital form. 3.1.16 Components
Circuit units or components (probes, sensors, etc.) that are connected in series with the instrument in a certain manner, may be essential components that are normally connected,
G8/T14913-94
3.1.15.1 Interchangeable accessories have their own durability and accuracy indicators and are not restricted by the device with which they are connected. 3.1.15.2 Interchangeable accessories nor.interchangeable accessories or components that require independent adjustment of the characteristics of the device: Under this ratio, this standard is confirmed to be used for the instrument and the following components. 3.1.17 Scaling is usually done by changing the measuring range of an instrument by means of amplification or attenuation before the digital/digital converter. Note: This is done by the 1-2-4-F two-dot operation code described above. HUNUREUTWENTYETGEI
Each 7
: boy
(a: Li's method
A whole production method requires a fixed
() number (ten
)
eight
(c? Unary system
Figure 1 is a diagram of the method of determining the loss of the method <See 3.1.10 to 5.1.12 3.2 Auxiliary terms
dist.factot
3.2.: Slightly variable
3.2-2 Warm-up time
warn-tine
The time required for the instrument to meet the requirements after the power supply is turned on under the specified conditions. 3.23 Preliminary adjustment
GB/T 14913—94
According to the manufacturer's requirements, the adjustment of certain adjustable components shall be carried out to ensure that the instrument reaches the specified accuracy. 3.2.4 Standard calibration
In the working state, the calibration voltage (3.2.5) is applied to the input terminal of the receiver, and the corresponding input value is compared with the standard value (3.2.6 series) for batch comparison, adjustment and calibration with the adjustment of the device performance, etc. 3.2.5 Calibration value reference Provide a sufficiently stable reference value, which can be connected to the internal or external positioner for comparison during calibration. 3.2.6 Calibration value The displayed digital or output value to be obtained by calibration. 3.2.7 The output information obtained when only a good power supply is connected, no input quantity is input, the input period is isolated from the external field, or when the manufacturer has special instructions to connect to other circuits. , this definition does not apply to other products that do not add quantity and do not give the total safety information of the zero position of the vehicle, such as the variable quantity or the "input avoidance" receiver.
The wide electrical book and the natural electrical certificate 3.2.8 Electrical zero adjuster A component used to adjust the electrical zero position to obtain a zero indication or a specific value. Note: The zero position adjuster is divided into a zero bias voltage adjuster and a public signal self-flow adjuster. 3.2.9b Source suppiy
The power supply required for the device to work
3.3 Terms related to input
3.3.1 The initial person in[.triuals
The power measurement (industry conversion) is connected to the instrument contact, 3.311 Non-asrmmetrical input 3.3.1.2 Scaled input syinmettical (bslaured) input A three-terminal input circuit with equal impedance to the other two terminals. 3.3.1.3 Scaled input d:feeiput
A high impedance circuit with a common terminal and the measured charge applied between these two terminals. Note: The two inputs are not subject to voltage drops to the common point in the circuit. 3.3.1,4 Single input gruurlrtl input (sing'--nleil iup1) In this input circuit, one input terminal is directly connected to the measurement ground and the other is the public terminal. 3.3.1.5 Loatia 3.3.1.6 The input circuit is connected to the output terminal of the machine and is insulated from the ground. 3.3.1.7 The input circuit is insulated from the ground and the public terminal, and is also insulated from the ground. 3.3.2 Initial measurement 3.3.2.1 Input (input signal) input: quantity (gain signal), note: In the case of error, the value of the quantity is the value of the quantity, 3.3.2.2 The rate of change of input power theinpuivoltage is the derivative of the voltage with respect to time,
CB/T14913-94
3.3.2.3 Mode voltage commandedvoltak is the component of value, phase balance, etc. existing between the two measurement terminals and the common terminal, and the common terminal can be taken as the ground terminal of the measuring panel. 3.3.2.4 Series modevoltage is the unwanted part of the input voltage added to the voltage being measured. Note that the thermal potential, the corresponding voltage and the AC ripple of the DC signal are all in the same voltage. 3.3.2.5 Input terminal pure feedback is generated internally and fed back to the input terminal of the instrument, or it is presented at an input terminal and the measuring ground (or shielding terminal) The pseudo signal.
3.3.2.6 Micro signalThe current, which is small, is largely independent of the external circuit. 3.3.3 Impedance at the Input Terminal 3.3.3.1 Source Impedance The output impedance of the signal source connected to the instrument input terminal. 3.3.3.2 Impedance The impedance of the input current presented between the instrument input terminals under working conditions. 3.3.3.3.3 Equivalent input impedance When the instantaneous current flowing into the input circuit is a nonlinear function of the instantaneous value of the transient voltage under given rated voltage and positive voltage conditions, the equivalent input impedance of the instrument is composed of resistance and reactance. The equivalent circuit absorbs the same active power as the above input circuit. And the current flowing into the equivalent circuit is equal to the wavelength of the nonlinear input current flowing into the receiver. 3.3.3.4 Other impedances The instrument is under working conditions: any of the following pairs of terminals (excluding input terminals and output terminals) are connected to the service expansion: each input terminal, each output terminal, input ground, case, voltage regulator and protective ground Note: This type of combination can be delayed by "capacitors" or "resistors". 3.3.3.5 Non-working input impedance coudininm The impedance of the added circuit measured between the input terminals in the non-working state. 3.3.4 Input impedance || tt || 3.3.4.1 Common mode interference The change in output information caused by the common mode circuit (3.3.2.3). 3.3.4.2 Crosstalk The change in output information caused by the common mode circuit (3.3.2.4). 3.3.4.3 Common mode rejection factor The change in output information caused by the common mode circuit (3.3.2.4). The ratio of the value of the common-mode voltage at one end of a function to the value of the input signal required to produce the same output value. The two terminals are connected to a specified circuit. E.3.3.4.4 Scricamodereception factor The ratio of the interference voltage to the increase in the input signal required to produce the corresponding output information compensation change. Note: The common-mode rejection ratio and the common-mode rejection ratio are expressed in terms of passband (or percentage). They may be used in different directions. 3.4 Terms related to instrumentation 3.4.1 Conversion 3.4.1.1 Linear conversion The ratio of the change in output value to the change in the previous input value is called a linear conversion. 3.d.2 Non-linear conversion The conversion of the input value function is the sum of the change in the value of the input and the change in the corresponding input value. Logarithmic transformation is a typical nonlinear transformation. 3.4.1.3 Transition point (transition point) The commutative command is a point in the table (3.5.2.2.3) that is not inside the table. At this point, the auxiliary change output signal (pointer) changes from a certain value to its adjacent value.
Note: The conversion point is divided into
The conversion point is at the center of each display unit. (a) The conversion point is only on the reverse side of the display unit [Figure 35], 3.4.1.4 Conversion command automatically changes the pulse or three of the week, A
-3/-2--/ 0 ---2 --
(a) The conversion point 1 represents the center of the unit z
+0|+ +21
(b) The code conversion point is located at the location of each table unit late code point
A slow report storage S number book HIC—conversion waiting
3.2 Basic working method According to the basic :or% f :pritlim source, the typical working modes are: familiar mode:
limited tracking mode
Note: The other two working modes are
Han standard mode,
minimum value mode,
GB/T14913-94
3.4.2.1 TrirRered modeof operatinm In this mode, the conversion command comes from outside the instrument (three-way or electric fusion). 3.4.2.2 Repeat (cyclie) mode of operation In this mode, the change command is initiated by the internal time extension: 3.4.2.3 Tensioning operation, truking ude uf ujiuralwI In this mode, the change command is initiated by the internal good circuit that can control the change of the escape (change quantity (3.7.4.3.3)). 3.4.3 Operating principle
3.4.3.1 Full value conversion ins1ar1aneou%valueconversion During the conversion period, the conversion of the effective input quantity is obtained in half of the time. 3.4.3.1.1 Regression approximation suessivuu[proximatiun =ypc This operating principle uses a reverse voltage generator to generate a series of adjustable voltages corresponding to binary or decimal half, which are compared with the normalized input voltage in a prescribed descending order of value. 3.4.3.1.2 Servo balancing In this type of working principle, the feedback signal generator includes a digital indicator glass combined with a follow-up control feedback unit to continuously compare the feedback voltage with the standardized input voltage. Their position detection follow-up unit re-establishes a balanced state and changes the digital indication when it is high. 3.4.3.1.3 Linear generation type linrirTump1 In this type of working principle. The convex voltage generator periodically generates a voltage (ramp signal) that changes linearly with time according to the level detector. It compares it with the standardized input voltage and the specified multi-reference voltage respectively. The time between the positive and negative voltages is obtained from the quotient. 3.4.3.1.4 Step ramp The working principle of the step ramp is different from that of the linear ramp type in that the ramp is composed of equal electric function steps, and the number of steps is counted in reverse. 3.4.3.2 Integral transformation The transformation that obtains the digital representation of the incident integral value within a specified time. 3.4.3.2.1 Input quantity alignment transformation type This working principle is to convert the normalized input into a current proportional to the input value, and then use this current to charge the device within a specified time (called timing!). The time required to discharge the input and generate electricity is proportional to the integral of the input: the adjustment is often used and the effect is naturally distributed at this time. . 3-4.3-2-3 Improved dual-glope type improved duel-glope type In order to improve the performance of the dual-glope analog/digital converter, improvements are often made to the effective duel-glope type. For example, when the integral and the fixed value are used for the blood sample attenuation, the integral is made at the beginning of the integrator output T to ensure the accuracy (irrelevant to the measurement) to avoid the influence of the hysteresis of the comparator:) In the fixed period, multiple reference voltages (currents) can be used to shorten the integral time to obtain high resolution, and the blind period (blind integration period) can be used until the next timing is started to perform analog calibration 4 to improve zero stability. The dual-glope cycle is continuous: the first time uses two poles to zero, and the second time is aimed at the measurement port, and the calibration time affects the measurement result. 3.4.3.2.4 Pulse Width Modulation PwM unTsir A continuous input type and split/digital converter, whose period amplitude is stable and the duty cycle of the square wave is limited by the effective measured input quantity. The pulse width is measured by the method to obtain the effective input quantity of the measured input.
3.4.3.2.5 Multi-transformation rmhilurnrcnversia is a double-slope improvement. At each time, the measured weight, internal and other reference quantities must be integrated in combination. The half-segment integration reporting rate is not increased. The device outputs multi-slope waveforms.
GB/T14913—94
For example: Note that it is necessary to introduce the integration of the reference quantity in stages for many times to expand the dynamic range and obtain the high value of the information, or introduce multiple references in the fixed value integration to obtain the middle and low value of the information, thereby improving the speed of the transformation and ensuring high resolution. 342 self-converting converter harebalaneconverson a continuous integrator/digital converter without beat control, the charge on the integrating capacitor is in a level state, and the product of the integral capacitor is conducted to the digital representation of the input signal, 3.4.3.3 extract the fractional inverse transform inrgralingleedhackcombinedcnnversion by the comparison method to obtain the information, and feed the corresponding analog quantity to the input end, and then use the fractional method to measure the difference to obtain the low-digit value: from the blood to improve the conversion, to ensure high resolution, 3.4.3.4 remainder is then circulated to compare the input signal with the digital network benchmark to obtain the required byte signal, amplify the difference (number), feed it back to the input for comparison, and obtain the lower byte information, and repeat this cycle to obtain the binary serial signal. 3.44 Time characteristics
Whether the various time characteristics listed in this document exist, overlap, delay or overlap depends on the working process of the instrument. The size and nature of the time characteristics depend on the internal characteristics of the instrument and the source of the resistance. 3.4.4.1 Transformation rate rnnvh!sinn rale the number of transformations obtained with a certain accuracy per unit time. 3.4.4.2 Total time
the time required for a monitoring measurement (Note: The point time and non-compressed period components given in Figure 3.1 are not equal to the point time when the working process is delayed and includes a single component. 3.4.4.3 Measurement time meesring The time from when the conversion command is sent to when the complete and valid digital information is obtained at the output terminal. 3.4.4.4 Detailed time 2ampling time
The time interval between the input and the output of the conversion circuit, the signal period
The fixed time
The time for the four-state fast conversion method to be removed (shutter, time
No depth and Figure 3 Example of components in the total time
ground
quickly determine
report effective
self-photograph
fall into you
determine the time wwW.bzxz.Net
lead the measurement time
GB/T 14913—94
recheck the order
white ton company
period entry limit
determine the time
1 conversion rate
account one conversion
measurement time
Figure 4 Example of two consecutive measurement sequences and their conversion rate drama 3.4.4.5 Input settling time titre plus the time required for the change to meet the requirements of the specified time. Note: The effect of exceeding the time may be allowed to be accepted! The shadow of the consumption is purchased. 3.M.4.6 is the time required for the stability time inturnulselingirut to meet the requirements of the change and the time required for the change to meet the requirements of the specified time. 3:4.4.7 bit time rcsettime
can be based on the time required from the change circuit core to the start of the device, 3.4.4.8 change time rng1:rgimg 3.4.4.9 The time required for the digitization to complete the sampling, digitization and encoding of the device! 3.4.4.10 The time required for the output signal to be displayed or for the entire output information to be transmitted to the terminal. 3.4.4.11 The time required for the output signal to be read and received at the effective value of the output signal after the overload value is eliminated. 3.4.4.12 The time required for the overload value to be eliminated until the measurement that meets the requirements of the enterprise can be carried out (full call). 3.4.4.13 The time required for the signal to change from a single signal to a stable indication that meets the requirements of extreme accuracy is 3.44.3. The time required for the signal to change from a single signal to a stable indication that meets the requirements of extreme accuracy is 3.44.3. tim In the case of no change in the basic range, the auxiliary signal is connected to the actual value change. The response time caused by the change can be 3.4.4.3.2 polar response oes
throw the bit number micro-selling fixed reputation value breaking the default change to lead to the polarity of the indication. 3.4.4.13.3 query response time rgspmtLime push the signal to the specified value to make the level of quality, so that the instrument needs to switch to the sweep state. The required response time does not cause the change. 3.5 Terms related to the output
3.51 input m5s
GB/T14913-94
The output signal is provided through the reverse contact of the false device in the form of a specified electric jade! Electric) or a specified resistance state (such as short pin or open circuit) to indicate.
3.5.1.1 Auxiliary niils The terminals other than the input and output terminals are used to provide or receive auxiliary analog or mathematical signals. 3.52
3.5.2.1 Output signal The value generated by the conversion chip.
3.5.2.1.1 Output signal\g\electrical output sisnalone\level is the electrical signal between a pair of output terminals used to represent binary "1". 3.5.2.1.2 Output signal\o\level autputsignal\zero\level is the electrical signal between a pair of output terminals used to represent binary "1". 3.5.2.1.3 Auxiliary output signal auxiliaryoutpulxig: ls is the output signal of the auxiliary input. It is used to evaluate and judge the output information. Typical auxiliary signals include clock, gate signal, stop signal and other command signals used by other devices. 3.5.2.1.4 Overload
When the output information is exceeded, it indicates the state of the environment. 3.5.2.1.5 Overflow indication ovcrlaindeasion is used to indicate the occurrence of leakage. 3.5.2.1.6 Monotonicity
When the When the input value changes in one direction, the difference between the output values of the two phases always has the same sign or is equal to zero, then the output is monotonic. 3.5.2.2 Auxiliary information total representation
3.5.2.2.1 Output information aurputindornalinm The mathematical representation (transformed basis) obtained during the change process (core information or display). 3.5.2.2.2 Output state outputstate The output state during the output period. 3.5.2-2.3 Display unit tearegentatiorunii The increment between two adjacent output states (see medical 5): Table 1 gives the description of different numerical units represented in decimal. Note: ① In the decimal representation, some of the positions may be left out to cause the display to progress. As shown in the table, the lowest position in the right column is the highest efficiency. The highest efficiency can only be used to connect \center\ to "1\" The sample force is taken from the head diameter and the total release of the output state during the process. si
Confirm the daily position quantity type
Table 4: A should
Connection code point transformation year single variable single space center (fixed diagram) A: The proposed input value has a disk solution 20009+2000mV (3.7.3.432000
Use group single monitoring, which contains 2×2000 single receiving, each ~ single is also 10, equivalent to 10mV (3.5.2.2.3) Medical 5 bit Mao letter indication
Stop
3.5.2.3 Output signal format
GB/T 14913-94
Example of output status
Indicates the unit
3.5.2.3.1 The output format seriesourput5ygrem consists of a series of consecutive binary digits on a pair of output terminals, 3.5.2.3.2 The serial output format is
All binary digits are simultaneously displayed on a pair of output terminals. 3.5.2.3.3 The serial output format is
123-L0F
A serial output format, which includes more than one pair of output terminals, can be displayed on these output pairs at the same time, and multiple characters can be displayed on these terminals continuously (for example: characters are serial, binary numbers are serial). Note that only the binary digits corresponding to the eleven binary digits in the parallel encoding are encoded in the subsequent single digits.
3.5.2.4 In the read-o:lockrate4 display or parallel output mode, each pair of binary digits provided in the unit time is the number of days. 3.5.3. Relationship between input and output
3.5.3.1 Common group force rsulmirm
Resolution cloud display method has the following two methods:
3. Convert the effect of measurement (the equivalent value of the independent h is expressed in units of teaching month (for example 11>>. Note that the external small given long old students, people out of the old north area, non-monotonicity or the like. Individual force change to push the error, the force high error card is not certain, 3.5.3.2 Conversion coefficient ronversion The ratio of the change in the output voltage to the change in the output voltage is expressed in the table. The value corresponding to the box is expressed in the table. 3.5.4 Test the resistance and the switch components. 3.5.A.1 The impedance of the output terminal is the impedance of the device in the working state. 3.5.4.2 The impedance of the output terminal is the impedance of the device. 3.5.4.3 The maximum voltage and the maximum charge current can be measured according to the supply voltage. If necessary, the polarity should be indicated. 3.6 About the lower part of the soft switch. 3.6.1 diider
battery storage, electric wear, inductance group my car must point H flower old and give the concave pressure proportional components, it can accurately match the required load pressure resistance to provide the required single internal pressure ratio
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