Transmitters that you don’t know

1. Concept Principle The transmitter is a converter that converts the output signal of the sensor into a signal that can be recognized by the controller. As the name implies, it means "change" and "send". "Change" refers to the conversion of various physical quantities from sensors into an electrical signal. For example, a thermocouple is used to convert the temperature into a potential; a current transformer is used to convert a large current into a small current. Since electrical signals are the easiest to handle, modern transmitters convert all kinds of physical signals into electrical signals. “Send” refers to the conversion of various electrical signals that have been converted into electrical signals from other sensors or control devices for the convenience of receiving and transmitting them. Once again, the electrical signals from the sensors are unified through electronic circuits. This constitutes the most commonly used modern transmitter.

2. Technical Standards General Specifications of Haiyan Jinhan Electric Transmitter Reference Standards and Rules: GB/T 13850-1998

Accuracy, etc.: 0.2, 0.5

Stability: in line with GB/T 13850-1998

Working temperature: I group 10-35oC

Group II 10-45oC

Group III - -10-55oC

Relative humidity: ≤95%

Response time: <400ms

Output ripple peak: <0.4%

Operating frequency: nominal frequency ±10%

Output Load: Constant Current Output Rated 10V Dropout Maximum 15V Dropout Constant Voltage Output Rated 2mA Maximum 5mA Output Output Load Effect: <0.04% (within the rated load range)

Input load: Current loop <0.2VA

Voltage circuit <0.1VA

Auxiliary power supply: rated voltage 80%-120%, rated frequency 90%-110%

Input overload range: current 3 times continuous 10 times 30 seconds 50 times 1 second 80 times 0.5 seconds voltage maximum 2 times continuous insulation strength: in line with GB/T13850-1998

Impact Test: ANSI C37.90a/1973, DIN IEC 255-4

(5kV 1.2/50us pulse voltage)

Surge test: IEC 255-4 (2.5kV-0.25ms/1MHz)

Calibration range: Minimum ±3% of full scale, minimum ±1% required.

Magnetic field influence: 100 centimeters 25 centimeter center change <0.025%

Storage conditions: temperature -40-70oC, relative humidity 20-99% non-condensing 3, good and bad to identify the market after the means of production, intensified fierce competition, but also because of the marginal discipline, many engineering designers on the transmitter Bad discrimination is relatively unfamiliar. Take a 0.5-level current-voltage transmitter as an example, you can identify the advantages and disadvantages from the following methods:

1, the reference must be stable, 4mA is the corresponding input zero reference, cold start 3 minutes 4mA zero drift within 40% less than 0.5%; load 250Ω pressure drop is 0.995-1.005V, foreign IC The chip uses an expensive energy gap reference, and the temperature drift coefficient varies by 10 ppm per degree.

2. The total consumption current of the internal circuit is <4mA, equals to 4.000mA after the setting is added, and the active rectifier filtering and amplifying constant current circuit does not change the current consumption due to the change of the primary input. The IC chip in foreign countries adopts constant current power supply;

3. When the working voltage is 24.000V, when the full-scale range is 20.000mA, the full-scale reading of 20.000mA will not change due to the change of the load 0-700Ω; the change does not exceed 20.000mA0.5%;

4. When the full-scale range is 20.000mA, when the load is 250Ω, the full-scale 20.000mA reading will not change due to the change of the working voltage 15.000V-30.000V; the change does not exceed 20.000mA0.5%;

5. When the primary side is overloaded, the output current does not exceed 25.000mA+10%;

6. When the working voltage is 24V reversed, the transmitter must not be damaged and must have polarity protection;

7, when the two lines due to induction and induced surge voltage exceeds 24V to clamp, do not damage the transmitter; generally in parallel between the two lines 1-2 TVS transient protection diode 1.5KE can inhibit every 20 The pulse of positive and negative pulse of 20 millisecond pulse width of one time interval of one second, transient withstand impact power 1.5KW-3KW;

8, the original side of the input overload must be limited: the original side of the input overload is greater than 125% when the output over-current limit 25mA + 10% (25.00-27.50mA) load 250Ω pressure drop is 6.250-6.875V;

9. Whether the surge voltage exceeds 24V or not when the clamp is recognized: In the two-wire output port and an AC 50V pointer meter, use the AC 50V to connect the two wires to instantly touch the two-wire output port to see if there is any clamp. Bit, how many volts can be clamped at a glance.

10, with or without polarity protection identification: with an analog multimeter by 10K file positive and negative measurement of the two-wire output port, there is always an infinite resistance Ω, there is polarity protection;

11. There is a prolonged short-circuit protection of the electrodeless output current: when the primary input is 100% or when the overload is greater than 125%-200%, the load is short-circuited to 250Ω, and the short-circuit protection limit is measured to be 25mA+10%;

Haiyan Jinhan series power transmitter adopts imported ASIC chip (special-transmitter thick-film circuit), super-linear voltage, current transformer and a full set of high-quality components, together with a full set of high-precision production equipment and computer detection calibration system. International quality assurance system ISO 9001:2000 assembly production, specifications, high taste. There are voltage, current, active/reactive power (spanning or sinusoidal reactive power), active/reactive power, frequency, power factor, DC voltage/current, total power adder and other full specifications of the power transmitter. High degree of integration, more reliable work, excellent temperature characteristics and long-term stability, good resistance to electrical shock and overload capacity, high level of accuracy and linearity, is a kind of complete calibration and maintenance The trusted third-generation power transmitter. FP series transmitters meet the requirements of IEC, ANSI, BEAMA and other related standards and reach the advanced level of similar products in the world.