4-20mA Signal Generator Module

Adjustable 4-20mA Current Signal Generator Module

Calibrator Simulator Tester PLC Analog Input Inverter Valve Positioner Actuator Panel Instrumentation Transmitter Recorder

     The 4-20mA Signal Generator Module is a small current source board powered from 12V-24V DC that outputs a current signal adjustable between 4mA and 20mA. The output current is set with the knob of the precision potentiometer on the board and read on the 3-digit LED display with 0.1mA resolution; no separate ammeter is needed for adjustment.

     Supply and output connections are on a 4-way screw terminal (VDD, GND, Out, GND); the supply input has reverse polarity protection. The 50mm x 50mm board has a mounting hole in each corner. The module is used to test PLC analog inputs, inverter current reference inputs, panel indicators and valve positioners in the field without connecting a real sensor or transmitter.

     Unlike the 0-10V / 4-20mA voltage to current converter module, it needs no input signal: the current value is set directly with the knob and seen on the display. An English user manual is included.

Key features:

     Direct reading on the display: The 3-digit LED display shows the output current in mA with 0.1mA resolution; test points such as 4.0mA, 12.0mA and 20.0mA are set by looking at the display.

     Fine adjustment by knob: With the cylindrical precision potentiometer and fitted knob, the current is changed in fine steps across 4mA - 20mA; the output follows the knob immediately.

     Industrial supply: Runs from the 12V or 24V DC supply found in control panels; reverse polarity protection on the supply input protects the board from wrong wiring.

     Screw terminal connection: VDD, GND, Out and GND are on a 4-way screw terminal; wires are connected without soldering.

     Small mountable board: The 50mm x 50mm board can be fixed into a test box or panel through the holes in its four corners.

Features:

• Product type: adjustable 4-20mA current signal generator (current source) module
• Model: 4-20mA Signal Generator Module
• Output current range: 4mA - 20mA
• Display: 3-digit 7-segment LED, shows the output current in mA
• Display resolution / adjustment accuracy: 0.1mA
• Adjustment: cylindrical precision potentiometer with knob
• Supply voltage: DC 12V - 24V
• Reverse polarity protection on the supply input
• Connection: 4-way screw terminal (VDD, GND, Out, GND)
• Output: current leaves from Out and returns through GND
• Load resistance (12V supply): max. approx. 350Ω
• Load resistance (24V supply): max. approx. 800Ω
• Response: output changes as soon as the knob is turned
• Compatible devices: PLC, inverter, panel indicator, recorder, valve positioner with 4-20mA current input
• Mounting: mounting hole in each corner of the board
• Material: green PCB, open board, blue screw terminal, black knob
• Dimensions: 50mm x 50mm (board)

Usage information:

• Connect the + of the 12V-24V DC supply to VDD and the - to the GND next to it. Connect the + of the current input device to Out and its - to the other GND terminal.
• Turn the knob to set the required current on the display. 4.0mA is the start of the scale (0%), 12.0mA the middle (50%) and 20.0mA the end (100%).
• Compare the value read on the PLC or indicator with the module display to check the input channel scaling and the wiring.

Applications:

•  Testing and commissioning PLC analog current inputs
•  Trying the current reference input of inverters (frequency converters)
•  Proportional valve and valve positioner adjustment
•  Electric actuator and damper position control tests
•  Checking panel indicators and digital panel meters
•  Current loop simulation instead of a transmitter (sensor simulator)
•  Testing recorder and data acquisition inputs
•  Instrumentation training and laboratory experiments
•  Troubleshooting 4-20mA signal lines in automation systems
•  Field and workshop checks as a simple calibrator

Precautions:

•  If the total loop resistance (device input + cable) exceeds approx. 350Ω with a 12V supply or approx. 800Ω with a 24V supply, 20mA cannot be reached. Use a 24V supply for high-resistance loops.
•  The supply must be regulated DC 12V - 24V; do not apply a voltage above this range.
•  The module only generates a current signal; it has no 0-5V / 0-10V voltage output and takes no external input signal.
•  The module is not a laboratory calibrator. For precise calibration work, verify the output current with a calibrated ammeter.

Package contents:

•  1 Pc 4-20mA Signal Generator Module
•  1 Pc adjustment knob ( Assembled )
•  1 Pc user manual (English)
•  Note: The 12V-24V adapter and connection cables are not included.