FNIRSI SG-003A Signal Generator User Manual

1. User Notice

This manual details the product's usage, precautions, and related matters. Please read it thoroughly before use to ensure optimal performance.
Do not use the instrument in flammable or explosive environments.
Used batteries and discarded instruments should not be disposed of with household waste. Please follow national or local legal regulations for disposal.
If any quality issues or questions arise regarding the instrument's use, please contact "FNIRSI" online customer service or the manufacturer. They will assist you promptly.

2. Product Overview

2.1 Main Specifications and Parameters

Signal	Range	Accuracy Error	Resolution	Max Load	External Power
Active Current (mA) Output	0~24mA	± (0.1%+0.005)	0.01mA	750Ω
Passive Current (XMT) Output	0~24mA	± (0.1%+0.005)	0.01mA		0~30V
Voltage (V) Output	0~24V	± (0.1%+0.005)	0.01V
24V Loop	0~24mA	± (0.1%+0.005)	0.01mA
Frequency (Hz) Output	0~9999Hz	±2%	5 digits
Current (mA) Input	0~24mA	± (0.1%+0.005)	0.01mA
Voltage (V) Input	0~30V	± (0.1%+0.005)	0.01V

2.2 Practical Function Introduction

Engineering Quantity Display Conversion: Signals can be displayed as physical values or engineering values (pure numerical values). Physical quantities correspond linearly to engineering quantities. For example, a 4~20mA current signal corresponds to 0~100, where 4mA corresponds to 0, 12mA to 50, and 20mA to 100. This range can be modified via parameters.
Preset Values: Four sets of commonly used signal values can be preset for quick output adjustment.
Signal Conversion: Input signals can be converted to output signals, allowing conversion between different physical quantities. For example, a frequency signal input with a range of 0-1000Hz can be converted to a 4-20mA current signal.
Programmed Output: This function allows for automatic continuous output changes based on set parameters, offering three modes: monotonic increase, monotonic decrease, and cyclic.
Real-time Curve: Displays the trend of input and output signal changes by plotting curves. Sampling time for the curve can be set, and the display range can be automatically adjusted within a certain period to the maximum and minimum values.
Modbus Slave: Can communicate with configuration software or PLCs via RS485 to set up the instrument.
Firmware Upgrade: Firmware can be upgraded via USB simulated U disk.

2.3 Interface Terminals

Diagram shows the top panel of the SG-003A with four 4mm diameter wiring jacks labeled from left to right: COM (black), OUT (red), IN-(24V) (blue), IN+(<30V) (yellow).

Output + ⟵ COM OUT IN-(24V) IN+(<30V) ⟶ Input +

Output - ⟵ COM OUT IN-(24V) IN+(<30V) ⟶ Input - / (24V)

The top surface has four 4mm diameter wiring jacks, marked with different color rings:

The blue port (IN-) is a multi-purpose function, serving as an input negative terminal and also switchable to a 24V independent test power supply. When in input mode, the (IN-) port is internally shorted to the black (COM) port; when acting as an independent power supply, there is 24V voltage between the (IN-) port and the (COM) port.
The red (OUT) port and the black (COM) port form an output port pair.
The yellow (IN+) port and the blue (IN-) port form an input port pair.
When the (IN-) port is an independent power supply, it can also be called the (24V) port, and it forms an output port pair with the (COM) port.

Warning!!! The safe limit voltage for the input terminal is not greater than 30Vpp. Exceeding this limit may damage the internal circuit.

2.4 Power Supply and Charging

Internal Battery: Uses a 3000mA high-capacity lithium battery for power supply.
Battery Level Display: The upper right corner displays the current battery level.
Charging Interface: Type-C interface (DC 5V).
Charging Status: The power button light shows red when charging, automatically stops charging and shows blue light when fully charged.

Diagram shows the bottom of the device with a power button and a Type-C charging port.

Power Button ⟵ Type-C Port

3. Keypad Panel Introduction

All buttons are made of white translucent silicone material. Colored LED backlights are set under the keys, allowing the key surface to change color with function and mode changes, providing more intuitive status indication.
The keys are mainly divided into the "Three-Key Area" and "Five-Key Area". Each key has multiple functions. The [FN] key and the keys in the "Five-Key Area" have upper/lower shift markings, which change according to the [FN] key status and interface mode. The default upon power-on is the upper shift function.
The [FN] key status is divided into: default white light status and red light status.
The "Five-Key Area" status is divided into: white light (manual setting mode); green light (preset output mode); blue light (programmed mode); no light (conversion mode).

Function Definitions

Diagram shows the SG-003A device with numbered labels pointing to specific buttons and screen areas.

RUN Light: Lights white when powered on and when output is enabled.
IN Input Key: On the main interface, used to switch input signal modes; when the [FN] key is red, single-click to enter input settings.
OUT Output Key: On the main interface, used to switch output signal modes; when the [FN] key is red, single-click to enter output settings.
FN Exit/Return Key: On the main interface, short press to change the [FN] light color. When the red light is on, it enables the secondary functions of other buttons (entering different modes, etc.); when in a setting interface, it acts as a return key.
Main Interface: The main display screen.
PRESET Up Function Key: When the key light is white, it increases the numerical value or selects upwards (same as programmed mode when the output pulse quantity and cursor are not present); on the historical curve interface, it quickly shifts right by 100; when the [FN] key is red, single-click to enter/exit the preset output mode (key light green), after which the up, down, left, and right keys can quickly call up preset signal values.
AUTO Left Function Key: When the key light is white, it selects left (same as programmed mode when the output pulse quantity and cursor are not present); on the historical curve interface, it shifts the cursor left point by point; when the [FN] key is red, single-click to enter/exit programmed mode (key light blue), after which the up key is single output, down key is reset, left key is end current output, right key is pause/continue.
ON/OFF Confirm Key: On the main interface, it enables/disables output; on the setting interface, single-click to confirm.
CURVE Right Function Key: When the key light is white, it selects right (same as programmed mode when the output pulse quantity and cursor are not present); on the historical curve interface, it shifts the cursor right point by point; when the [FN] key is red, single-click to switch between curve interface/character interface.
CONVERT Down Function Key: When the key light is white, it decreases the numerical value or selects downwards (same as programmed mode when the output pulse quantity and cursor are not present); on the historical curve interface, it quickly shifts left by 100; when the [FN] key is red, single-click to enter/exit conversion mode (no light), after which the up, down, left, and right keys have no function.

4. Display and Signal Description

Diagrams show two display interfaces: one for input signal settings and one for output signal settings. Both show time (T:00:09:30), signal type (mA, V, XMT, Hz, 24V), basic settings, engineering quantity, calibration, mode (actual input/output, range input/output), programming output, preset, loop voltage (12V, 24V), and ranges (0-24mA, 4-20mA, 0-20mA, 0-10mA, USER).

4.1 Signal Type Switching

On the main interface, first press [FN]. Once the [FN] key light turns red, to switch the input signal type, press the [IN] key to enter input settings.
To switch the output signal type, press the [OUT] key to enter output settings. After entering the setting interface, you can directly select the desired signal type by pressing left or right, then press [FN] to exit to the main interface.
Under various signal types, there are multiple signal modes available for switching. Each signal type also has different parameters that can be set.

4.2 mA Current Signal

Mode Switching: On the main interface, when [FN] is white, press [IN/OUT] to switch the display between actual input/output values and engineering values.
Output Open Circuit Detection: When output is enabled, if the interface shows "Open Circuit" and flashes, it indicates that the output signal is not connected or the output is close to zero.
Output Loop Voltage: The no-load voltage of the current output can be set. 12V is for power saving, while some devices require 24V driving capability.
Output Range: The limit range for current output can be set.

4.3 V Voltage Signal

Mode Switching: On the main interface, when [FN] is white, press [IN/OUT] to switch the display between actual input/output values and engineering values.
Overcurrent Protection: If the output voltage is short-circuited, the output will automatically shut down.
Output Range: The limit range for voltage output can be set.

4.4 XMT Passive Current Signal

Mode Switching: On the main interface, when [FN] is white, press [IN/OUT] to switch the display between actual input/output values and engineering values.
Output Range: The limit range for passive current output can be set.

4.5 Hz Pulse Signal

Mode: The pulse signal has four modes: Frequency, PWM duty cycle, Speed Frequency, and Pulse Quantity/Count. On the main interface, when [FN] is white, long press [OUT] to switch modes.
Range: Select the range for frequency output: 0~99.999Hz, 0~999.99Hz, 0~9999Hz, 0~200kHz.
Method: Select level/open circuit based on pull-up/no pull-up.
Output Peak Value: The voltage height of the output waveform, maximum is 24V.
Frequency Mode Operation: The frequency range can be switched on the main interface when [FN] is white by pressing [OUT].
PWM Mode Operation: PWM displays frequency value (i.e., period value) and two parameters for duty cycle. The frequency value will be displayed in the original engineering quantity position (no engineering quantity display). Note that the maximum frequency does not exceed 9999Hz. Both frequency value and duty cycle parameters can be set during output. On the main interface, when [FN] is white, press [OUT] to switch, indicated by a yellow cursor.
Speed Mode Operation:
1. Speed mode is used to calculate the speed of motors or gears. If a motor or gear produces 1 pulse per revolution, and it rotates 3000 revolutions per minute, then 1 second is 50 pulses.
2. Time Unit: Frequency = RPS (revolutions per second) * pulses per revolution, RPM (revolutions per minute) = RPS * 60, RPH (revolutions per hour) = RPS * 3600. In speed setting selection, note that the maximum frequency does not exceed 9999Hz.
3. Pulses per Revolution: The number of pulses per revolution for a motor or gear, selected in speed settings.
4. Missing Teeth: Primarily used to simulate engine speed, selected in speed settings.
Quantity Mode Operation:
1. The main purpose of pulse quantity is to simulate flow rate control sensors. The frequency value will be displayed in the original engineering quantity position.
2. The period is displayed in the original engineering quantity position, in milliseconds. On the main interface, when [FN] is white, press [OUT] to switch between period and quantity values, with cursor distinction. The period value can be modified during quantity output.
3. In this mode, after enabling output, the cursor disappears, and the backlight of the up, down, left, and right keys turns blue. The functions of the up, down, left, and right keys also change: up is single pulse send, down is program stop and reset, left has no function, right is start/pause.

4.6 24V Loop Detection

On the OUT signal type interface, select the "24V" tag by pressing left or right to enter this function. In this state, the main interface displays the 24V loop current; it does not restrict the type of input signal detection.

Loop One: After enabling output, 24V voltage is output between the (OUT) port and the (COM) port, and the loop current is detected and displayed in the "Output 24V Loop" area. This function can be used to test devices such as pneumatic control valves or two-wire transmitters, providing them with 24V power and detecting current.
Loop Two: After activating the independent 24V power supply, 24V voltage is output between the (IN-) port (i.e., 24V port) and the (COM) port, without affecting the detection type of the input signal at the (IN+) port. If the input signal type is selected as mA at this time, the (IN-) port can cooperate with the (IN+) port to form a 24V output, and simultaneously detect the current in the loop, similar to Loop One.
The (IN-) port can be switched to an independent 24V power supply function, which outputs a single DC24V voltage. At this time, the (24V) port can be used with the (IN+) port to test two-wire transmitters.

Note!

The difference between 24V loop detection and independent 24V is: 24V loop detection uses the output signal port to measure feedback current.
The independent 24V port can form a 24V power supply with the output negative port, or it can be combined with the input positive port to power the transmitter and measure the transmitter's feedback current.

Mode Switching: On the main interface, when [FN] is white, press [OUT] to switch the display position of the actual loop current value and engineering quantity.
Activate Independent 24V: If this option is checked, the independent 24V power supply will output from the (24V) i.e., (IN-) port and the (COM) port, and will not be affected by input and output signal type switching.
Activate Hold: If this option is checked, the 24V status will be maintained from the last power-on state each time the device is turned on. Otherwise, 24V needs to be manually enabled each time.

5. Extended Functions

5.1 Engineering Quantity

In industrial applications, analog signal values often need to be converted into engineering values. Therefore, this instrument allows setting the upper and lower limits of engineering values and corresponding signal values for each signal's input and output settings.

5.2 Preset Values

Parameter Settings: You can set the signal values corresponding to the up, down, left, and right keys.
Operation: To activate and exit: On the main interface, when [FN] is red, press the up key [PRESET] to activate/exit preset mode.
Up, Down, Left, Right Keys: After activating preset mode, the backlight of the up, down, left, and right keys turns green. The functions of the up, down, left, and right keys will change to output the set values.

5.3 Signal Conversion

Input signals can be converted to output signals. For example, an input frequency signal can be converted to a current signal, with an input range of 0-1000Hz converting to 4-20mA.
Parameter Settings:
1. Input Upper/Lower Limit: Amplitude range of the input signal.
2. Output Upper/Lower Limit: Amplitude range of the output signal.
3. Over-limit Allowance: For example, 1-5V converted to 4-20mA. If the user checks this option, when the input is 0V, the output will follow to 0mA. If the user does not check this option, the output will be 4mA, and the output will be locked within the set range.
4. Auto Run: If this option is checked, signal conversion will automatically start at the next power-on. Exiting signal conversion will cancel auto-run.
Operation:
Activation and Exit: On the main interface, when [FN] is red, press the [CONVERT] key to activate/exit signal conversion mode. After activation, the backlight of the up, down, left, and right keys will turn off and have no function.

5.4 Programmed Output

Programmed output can automatically complete N cycles of signal output according to user-set parameters. This function is mainly used for aging tests of electric or pneumatic valves, or for PLC program debugging and testing.
Parameter Settings:
1. Mode: Divided into three modes: single increase, single decrease, and cyclic.
2. Cycle Count: 0 is infinite, 30000 is the maximum count.
3. Start Value: The value at the beginning of each cycle.
4. End Value: The value at the end of each cycle.
5. Increase Step Value: The value to increase by each time.
6. Increase Step Time: The time interval between each increment.
7. End Hold: The delay time at the end value.
8. Decrease Step Value: The value to decrease by each time.
9. Decrease Step Time: The time interval between each decrement.
10. Cycle Hold: The delay time at the start value.
Parameter Description Supplement: For single increase and single decrease, the start and end values are selected based on high and low, and will not automatically close.
Operation:
1. Activation and Exit: On the main interface, when [FN] is red, press the left key [AUTO] to activate/exit programmed output mode.
2. Up, Down, Left, Right Keys: After activating programmed output mode, the backlight of the up, down, left, and right keys turns blue. The functions of the up, down, left, and right keys also change: up is single run, down is program reset, left is single step run, right is pause/continue.

5.5 Real-time Curve

Operation: On the main interface, when [FN] is red, press the right key [CURVE] to switch between curve interface and non-curve interface.
Parameter Description:
1. Enable Output Curve: Enables the follow-up display curve of the output signal (red line).
2. Output Auto Scaling: Automatically adjusts the output signal scale range, automatically adjusting the y-axis scale range based on the maximum and minimum values of the curve.
3. Input Auto Scaling: Automatically adjusts the input signal scale range, automatically adjusting the y-axis scale range based on the maximum and minimum values of the curve.
4. Sampling Time: The refresh interval time of the curve, the time scale will also change accordingly.

5.6 Output Time

Output Activation Time: If checked, the output will automatically turn off after the set output time expires.
Output Time: Set the duration of the output.

5.7 Communication

USB Connection: Uses a USB virtual serial port for communication.
Slave Address: Modbus slave address. (Refer to Appendix 1, 2, 3 on page 12 for instrument register addresses and descriptions).

6. Wiring Methods

Diagrams illustrate wiring connections for the SG-003A with PLC/Process Instruments.

Diagram 1: Shows the SG-003A connected to a PLC/Process Instrument. The device's COM, OUT, IN-(24V), and IN+(<30V) ports are connected. This setup is for universal signal output (current/voltage/frequency) fully switched by electronic switches.

Diagram 2: Similar to Diagram 1, showing the SG-003A connected to a PLC/Process Instrument for universal signal output (current/voltage/frequency) fully switched by electronic switches.

Diagram 3: Shows the SG-003A connected to a pneumatic valve for valve setting and feedback. The input (-) port is switched to 24V, providing power for valve feedback input and simultaneous output.

Diagram 4: Shows the SG-003A connected to a pneumatic valve for valve setting and feedback. The input (-) port is closed for 24V, serving as the negative pole for input signals, and simultaneous input and output are performed.

7. Troubleshooting & Instrument Maintenance

7.1 Troubleshooting

Instrument does not power on:
1. Check if the battery is charged and if the charging indicator light is normal.
2. Incorrect operation during firmware upgrade may cause the system to crash.
Screen display abnormal: Check if the screen connection is normal.
Output or measured values abnormal:
1. Check if the signal cables are connected correctly.
2. Check if the signal type is selected correctly.
3. If the connection exceeds the technical specifications, it may cause the instrument to malfunction or even be damaged.
Input/output error: This is a normal phenomenon because input and output are not isolated.

7.2 Instrument Maintenance

This instrument is powered by a 3.7V rechargeable lithium battery. For long-term use, please use a power adapter to extend battery life.
This instrument is not waterproof. Do not use it in high humidity environments. Do not place the unit in unstable places or where it may be subjected to strong vibrations.
Do not place the unit in high humidity, dusty, direct sunlight, outdoors, or near heat sources.

7.3 Firmware Upgrade

This instrument currently uses a USB simulated U disk for firmware upgrades.
Steps for Use:
1. Insert the instrument into the PC, power on, and wait for the PC to recognize a U disk named "Bootloader".
2. Copy the upgrade firmware to the U disk.
3. Wait a few seconds, and the device will power on normally, indicating a successful upgrade.