What is a multifunction calibrator?
- Multifunction calibrators are flexible instruments with a sophisticated array of electronics suitable for reading and sourcing voltage, current, frequency, and resistance signals from nearby sources.
- These calibrators are designed to perform various types of calibrations in industrial applications.
- These calibrators source, simulate and measure various process parameters such as pressure, temperature, and electrical signals with exceptional precision single compact, hand-held device.
- Through these multifunction calibrators, the calibration procedures can be automated to store data and even troubleshoot instruments that are HART compatible.
- Multifunction calibrators circumscribe a wide range of capacity to cover a testing workload for electrical and electronic test equipment and various types of instrumentation.
- Periodic calibration and maintenance of instruments and sensors are required as they are subjected to change over time or usage due to drift, environmental factors, process changes, output loop changes, and so on because the information received from measuring instruments must be reliable and accurate.
- These multifunction calibrators are nicknamed Do Everything calibration instruments.
What are the features of MFC?
Key features of multifunction calibrators
- Calibrates both temperature and pressure transmitters.
- Measures, sources, and simulates mA loop parameters Volts DC, frequency, and resistance.
- It has an inbuilt 24 V loop power supply.
- It has a store and recalls frequently used calibration setups.
Input/Output Terminals and Connectors of multifunction Calibrator:
Input and output description is show in Table #1
|1||Pressure module connector|
|2 & 3||Terminals to measure Volts in V, & Current in mA.|
|4||Thermocouple Input and Output|
|5 & 6||Terminals to source or measure the voltage in V, resistance in ohms, frequency in Hz, and RTDs.|
|7 & 8||Terminals to source or measure current in mA, and perform 3-wire and 4-wire RTD|
Describe functional keys of Multifunction Calibrator:
The functional keys of MFC are shown below Table #2
|1||Switch ON/OFF the power supply.|
|2||Selects the voltage, Current, or Loop Power measurement function in the upper display|
|3||Pressure measurement function is selected in the upper display,|
|4||Reading (Value) of the pressure module is made to Zero, This will apply to both the upper display as well as lower displays|
|5||During powering Up turn on or turn off the backlight to adjust the contrast.|
|6||Frequency measurement, resistance measurement, and sourcing functions are toggled.|
|7||Toggles between Degree Centigrade or Degrees Fahrenheit in the case of thermocouples and RTD Functions|
|8||Recalls from memory a source value corresponding to 100 % of span and sets it as the source value. Press and hold to store the source value as the 100 % value.|
|9||Increments output by 25 % of the span|
|10||Decrements output by 25 % of the span|
|11||Recalls from memory a source value corresponding to 0 % of span and sets it as the source value. Press and hold to store the source value as the 0 % value. Identifies Firmware version. Press and hold when powering up.|
|12||Cycles through :|
Slow repeating 0 % – 100 % – 0 % ramp
Fast repeating 0 % – 100 % – 0 % ramp
Repeating 0 % – 100 % – 0 % ramp in 25 % step
|1-13||Enables and Disables Shut Down Mode|
|13||Increases or decreases the source level. Cycles through the 2-wire, 3-wire, or 4-wire selections. To move through the memory locations of the multifunction calibrator setup. In Contrast Adjustment mode, the up key darkens the display contrast, down key lightens the display contrast|
|14||Previous calibration setup from the memory location is recovered.|
|15||Saves the calibrator setup. Saves Contrast Adjust setup|
|16||In a lower display, the calibrator is cycled or rounded through MEASURE and SOURCE mode|
|17||The thermocouple measurement and sourcing function in the lower display are selected.|
|18||Toggles between voltage, current sourcing, or current simulation function in the lower display.|
|19||Selects RTD (resistance temperature detector) measurement and sourcing function in the lower display. Repeated pushes cycle through the RTD type|
|20||Selects the pressure measurement and sourcing function.|
How to use Multi-Function Calibrator?
1. Contrast Adjustment:
Use the following steps for contrast adjustment.
- Press key 1 to adjust the display contrast as required.
- Press and hold the upper navigation Key2 to darken the contrast.
- Press and hold the lower navigation Key3 to lighten the contrast.
- Press Key 4 STORE SETUP to save the required contrast level as adjusted.
2. Using Measure Mode Electrical Parameters (Upper Display):
To measure the electrical parameters such as the current or voltage output of a pressure instrument,
- Press the V mA LOOP key to select volt V or current mA. Note that the LOOP should be off.
- Connect the measuring Red and Black leads.
3. Current Measurement with Loop Power:
The loop power function of the multifunction calibrator will activate a 24 V supply in the series current measuring circuit to test a transmitter when disconnected from plant wiring. To measure current with loop power:
- Connect the multifunction calibrator to the transmitter current loop terminals
- Press the V mA LOOP key while the multifunction calibrator is in the current mA measurement mode. LOOP has appeared and an internal loop supply 24 V DC is turned ON.
4. Measuring Electrical Parameters (Lower Display):
Using lower display electrical parameters can be measured as shown below
- Make a connection to the multifunction calibrator
- If necessary, press MEAS/ SOURCE for measure mode in case of the lower display.
- Press the V, mA key for DC voltage or current, or Hz, Ω for frequency or resistance.
5. Measuring Temperature Using Thermocouples:
The multifunction calibrator supports all types of thermocouples. To measure temperature using thermocouples is shown below,
- Connect the thermocouple leads to the TC input/output using the appropriate thermocouple mini plug. One pin must be wider than the other pin. Don’t force a mini plug in the wrong polarization.
- If necessary, press MEAS/SOURCE for MEASURE mode.
- Press the TC key for TC display. If required, press this key to select the required thermocouple type or you can toggle between Celsius or Fahrenheit temperature units by pressing oC, oF
If the temperature of the multifunction calibrator and thermocouple plug is not the same, wait for one minute or more to stabilize the temperature of the connector after the mini plug is plugged into the TC Input/output.
6. Using Resistance-Temperature Detectors (RTDs):
The multifunction calibrator accepts all types of RTD. RTDs are characterized by their resistance at zero Degrees Celsius known as the “Ice Point” termed R0.
- Generally, the value of R0 is 100 ohm (Ω).
- The multifunction calibrator accepts RTD measurement inputs in 2 Wire, 3 Wire, or 4 Wire configurations,
- The most commonly used configuration is 3 Wire, the 4 Wire configurations bear maximum measurement precision, and finally 2 Wire configurations bear minimum measurement precision.
Temperature measurement using an RTD is shown below:
- If required, press MEAS/ SOURCE forMEASURE mode.
- Press Key19 “RTD” for the RTD display. Press this key continuously to select desired RTD type, if required.
- Press the Key 13 Upper Navigation or Lower Navigation Key to select a 2-Wire, 3-Wire, or 4-Wire connection.
- Connect the RTD to input terminals as shown in Figure above
- If required, you can toggle between temperature units Degrees Celsius or Degrees Fahrenheit by pressing. oC, oF
Calibration of Instruments using Multi-function calibrators:
1. Calibrating a Temperature Transmitter:
Calibration of the temperature Transmitter using the measurement (upper display) and source (lower display) modes is shown below.
- Connect the multifunction calibrator to the instrument under test temperature transmitter in this case.
- Press V mA LOOP for the current (upper display). If required, press
V mA LOOP once again to activate loop power.
- Press TC (lower display). If required, keep on pressing this key to select the desired thermocouple type.
- Press MEAS/SOURCE Key for SOURCE mode if necessary.
- Set zero and span parameters by pressing Key 13 Upper Navigation and Lower Navigation keys.
- Enter zero and span parameters by pressing and holding the Keys 0% and Keys 100%.
- Perform test checks at 0% to 25 to 50 to 75 and to 100% points by pressing Key 9 or Key 10, now adjust the transmitter as required.
2. Calibrating a Pressure Transmitter:
Calibrating a pressure transmitter using a multifunction calibrator is shown below.
- Connect the multifunction calibrator to the instrument under the test pressure transmitter in this case as shown in Figure above.
- Press key V mA LOOP for current (upper display). Press the same key V mA LOOP once again to activate loop power if necessary.
- Press the Key 20 for lower display.
- If necessary, press Key 16 MEAS/SOURCE for SOURCE mode.
- Zero the pressure module.
- Perform checks at 0% and 100% of the span and adjust the transmitter as necessary.
Calibrating an I/P Device:
The following test allows for calibrating a pressure-controlling device.
- Connect the test leads to the instrument under test current to the pressure controller in this case as shown in Figure above
- The connections arouse a current to the pressure transmitter and measure the corresponding output pressure.
- Press the Key 20 (upper display).
- Press the key V mA for sourcing current (lower display).
- If necessary, press MEAS/SOURCE for SOURCE mode.
- Enter the desired current by pressing Key 13 Upper Navigation and Lower Navigation keys. Press Right Navigation and the left Navigation keys to select different digits.
What are the benefits of Multifunction Calibrators?
- Operation is simple
- It has the ability to read, and source various process signals such as current, voltage, frequency, frequency, pulse, and resistance.
- It can measure and calibrate every instrument using only one instrument.
- It can perform various calibration types in a wide range of industrial applications.
It can easily be expanded with various pressure modules.