Choosing the right analog signal generator for PLC testing involves evaluating signal range, accuracy, power options, and ease of use. The following five products provide a variety of current and voltage outputs, multiple signal types, and useful features such as built-in displays and long standby times. This guide highlights each option and helps you compare capabilities for reliable lab and field work.
| Product | Brand | Key Feature |
|---|---|---|
| Riiai SG003A | Riiai Store | 4-20 mA / 0-24 V / multiple signal types |
| DROK 4-20mA Generator | DROK Store | Dual 0-20 mA / 0-10 V outputs |
| Adjustable Signal Generator | Unspecified | 4-20 mA / 0-12 V with short-circuit protection |
| SEESII MR9270S+HART | Seesii Store | 4-20 mA / 0-24 V / HART / real-time curves |
| DROK 4-20mA Generator 2pcs | DROK Store | Dual channel 0-20 mA / 0-10 V |
Riiai SG003A 4-20mA Signal Generator
The Riiai SG003A supports precise conversion across multiple signal types, enabling versatile PLC testing setups. It offers 4-20 mA current signals with precision down to 0.01 mA, 0-24 V voltage signals with 0.01 V resolution, XMT passive current signaling, and Hz pulse output up to 9999 Hz with high precision. A 2.4-inch TFT color screen provides clear visibility for daytime or night operation. The built-in 3000 mAh USB-rechargeable battery allows extended use, with up to approximately 26 hours of operation per charge. This model emphasizes flexibility and long-running capability for field diagnostics and bench setups.
Applications often involve converting input signals to various physical quantities for PLC testing, calibration, and simulation. The device’s battery-powered design reduces dependency on external power while the robust display and intuitive controls accelerate test setup. The combination of multiple signal types and a rechargeable battery makes it suitable for both shop-floor testing and on-site verification of control systems.
DROK 4-20mA Generator (0-10V)
The DROK dual-signal generator combines current and voltage output in a single module. It can generate 0/4-20 mA current signals and 0-10 V voltage signals with a simple, user-friendly interface controlled by a multi-turn potentiometer. This configuration is ideal for testing PLC input modules and recorder systems that require synchronized current and voltage signals. The compact design supports quick setup changes, making it useful for both development and field verification tasks.
With straightforward calibration options and a compact form factor, this DROK unit is well-suited for labs needing a reliable, affordable dual-output generator. It is particularly appealing for users who frequently switch between current and voltage tests or need a dependable baseline signal for device under test evaluations.
Adjustable Signal Generator 4-20mA / 0-12V
This adjustable signal generator delivers 0-24 mA current output (default 4-20 mA) and a voltage output adjustable up to ±12 V (default 0-10 V). A built-in 1500 mAh lithium battery underpins portability, with a charging cycle that typically takes several hours. Short-circuit protection and calibration accuracy around 0.03–0.05 V/A ensure safe operation and reliable test results. The device suits calibration tasks on PLC panels and LED testing setups where robust battery operation and shielded outputs are needed for extended sessions.
The unit’s take-off resistance below 500 ohms helps prevent overload, while the calibrated output provides a dependable reference for signal integrity testing. It is a practical option for technicians who require a compact, battery-powered signal source for field calibration and on-site validation of control systems.
SEESII MR9270S+HART 4-20mA Signal Generator
The SEESII MR9270S+HART offers an upgraded signal generator with broad compatibility for current, voltage, and sensor signals, including thermocouples and resistance-based measurements. It supports 0-24 mA current output, 0-24 V voltage output, and XMT passive current signals. Features such as HART communication, MODBUS master operation, and a paperless recorder provide advanced data handling and remote communication. The device includes a 2.4-inch high-definition LCD and clearly labeled silicone buttons for straightforward operation, even in demanding testing environments.
Programmable output and real-time curve display enable accurate signal profiling and test repeatability. Advanced modes let users define start points, end points, and cycles, while an automatic rise/fall function supports dynamic test scenarios. The MR9270S+HART is suitable for more complex calibration and signal conversion tasks, particularly in industrial automation and process control contexts.
DROK 4-20mA Generator 2pcs
This two-pack from DROK provides two independent channels capable of 0-20 mA current and 0-10 V voltage output. The dual-channel configuration is ideal for tests requiring simultaneous signal generation across two points, such as system cross-checks or comparative calibration tasks. The kit includes bright LED displays and back-to-back calibration controls that simplify adjustments and verification, making it a practical choice for labs needing redundancy and flexibility in a compact footprint.
The generators feature clear LED displays and calibration potentiometers on the back, enabling straightforward display and output calibration. This setup supports quick verification cycles and consistent signal delivery across multiple test points, which is valuable in production-line testing and educational lab environments.
Buying Guide
- Signal range and types: Look for units that cover the needed current (0-20 mA) and voltage (0-10 V or higher) ranges, plus any specialty signals (Hz pulse, thermocouple, or resistance) that your tests require.
- Accuracy and stability: Check calibration accuracy (e.g., ±0.01 mA, ±0.03 V) and how well the device maintains a stable output under load or during transitions.
- Power and portability: Battery-powered units are advantageous for fieldwork; consider battery capacity and charge time to avoid mid-test downtime.
- Display and interface: A clear LCD or TFT display, backlit controls, and intuitive menus reduce setup time and error potential in busy environments.
- Protection and safety: Short-circuit protection, overcurrent protection, and safe output limits help protect both the tester and the device under test.
- Programming and data logging: Devices that support programmable output, real-time curves, and data logging (especially with HART or MODBUS) enable thorough test documentation.
- Multi-channel options: For synchronized testing or comparative analysis, multi-channel generators or bundles (like two units in one kit) provide efficiency and consistency.
- Compatibility with test equipment: Consider how the generator integrates with PLC panels, LED testers, pressure or temperature transmitters, and other industrial sensors used in your workflow.