The rapid adoption of IEC 61850-based digital substations has made GOOSE (Generic Object Oriented Substation Event) protocol an integral part of modern protection systems. GOOSE enables high-speed peer-to-peer communication between Intelligent Electronic Devices (IEDs), significantly reducing hardwired signaling and improving reliability. Consequently, selecting a capable test system for verifying GOOSE-based tripping schemes and digital protection devices has become an essential consideration for utilities and field engineers.
This article presents a comparative review of mainstream digital relay protection testers that support GOOSE protocol, with particular emphasis on the KDJB-650S Handheld Digital-Analog Integrated Relay Protection Tester from Wuhan Kaidi Zhengda Electric Co., Ltd. The KDJB-650S stands out by offering precision at 0.05%—competitive with top-tier international brands—while being offered at a more accessible price point.
OMICRON’s CMC 356 is widely recognized as a benchmark in the relay testing industry. The unit delivers six current outputs (6×32A or 3×64A or 1×128A) and four voltage outputs (4×300V or 1×600V), offering extensive dynamic range and high power. GOOSE and Sampled Values (SV) testing are supported as standard, making it suitable for testing IEC 61850 IEDs and GOOSE tripping schemes in digital substations. Key specifications include: binary inputs (10), binary outputs (4), DC auxiliary supply output (0-264 VDC, max 50W), dimensions 450×145×390 mm, weight 16.8 kg, and 10-channel analog measurement and transient recording capability (optional).
Price indication: High market positioning; approximate purchase price around US$50,000–60,000 (estimated based on market equivalents; rental from US$375–600/day in Australia).
Doble’s F6150sv is a power system simulator specifically optimized for IEC 61850-based protection devices. It supports both GOOSE publish/subscribe and SV streams through fiber-optic and copper ports. The F6150sv features the highest output current of any test set on the market—available with an enhanced rating of 6×35A, 3×70A, or 1×210A. It provides up to 12 high-level analog sources (six voltage, six current). Wi-Fi capability is optional, and GPS time synchronization is built-in for end-to-end testing.
Price indication: Premium category; approximate US$40,000–50,000 depending on configuration and options.
Megger’s SMRT410D supports IEC 61850 GOOSE protocol as a user-specifiable option. The platform can provide up to four voltage and six current outputs, or up to ten current outputs. Current output channels are rated for 30A @ 200VA continuous (up to 60A @ 300VA for 90 cycles), with a unique flat power curve from 4A to 30A. The SMRT1 series also supports GOOSE and 9-2 LE sampled values testing, with voltage output of 0–300V/150VA, while the SMRT1B includes an optional battery power for field portability. The integrated Smart Touch View Interface enables standalone operation.
Price indication: Mid-to-high range; approximate US$25,000–40,000 depending on modules and configuration.
ONLLY’s F08A is a specialized optical digital relay protection test system designed for digital substations. It features eight independent optical fiber Ethernet interfaces, ten FT3 optical fiber interfaces (eight outputs, two inputs), supporting IEC61850-9-1/9-2 and IEC60044-7/8 (FT3) protocols with GOOSE functionality. The unit includes MMS communication capability for direct interaction with protection devices, GPS/IRIG-B/IEEE1588 synchronization, Wi-Fi remote control, eight binary inputs, and six general-purpose binary outputs plus two fast binary outputs. Automatic detection of optical digital signals for SMV and GOOSE configuration is supported.
Price indication: Mid-range Chinese manufacturer pricing; approximate US$12,000–18,000.
PONOVO’s POM2-3333 is a digital relay and merging unit tester with 0.05% high accuracy analog output. It supports GPS, IRIG-B, and PPS timing methods and can test SMV accuracy, data processing delay, clock synchronization, and abnormal SMV functions. The device is specifically designed for testing merging units with electronic transformer input, magnetic transformer input, and electromagnetic transformer input. GOOSE message analysis and abnormal condition simulation are built-in. Dimensions 390×210×287 mm, weight 14 kg.
Price indication: Approximate US$15,000–22,000.
GFUVE’s TEST-630 six-phase relay test system features a built-in high-speed industrial computer with embedded OS, 12-channel high-precision DAC simultaneous output, and protection mechanisms against over-current, over-voltage, overload, short circuit, and over-temperature. Connectivity includes RJ45 (Ethernet), USB, and industrial serial interface. However, detailed GOOSE protocol implementation documentation is limited compared to specialized digital testers.
Price indication: Approximately US$37,000.
The KDJB-650S represents a new generation of handheld integrated relay protection testers that bridge conventional and smart substation testing. Key specifications are detailed below.
The KDJB-650S achieves precision that matches top-tier international competitors. The current output accuracy is rated at 0.05%+0.1mA typical, with guaranteed accuracy of <0.08%rd+0.02%rg over the 0–20A range, and <0.15%rd+0.05%rg from 20A up to Imax. Voltage output guaranteed accuracy is <0.08%rd+0.02%rg across the full range. This level of precision qualifies the KDJB-650S for merging unit testing, a capability typically reserved for higher-cost instruments. This compares favorably with the 0.05% accuracy claimed by the PONOVO POM2-3333, while being offered at a substantially lower price point.
Unlike many conventional relay testers that remain heavy and bulky, the KDJB-650S is truly handheld, weighing less than 4.5 kg with dimensions of 278×191×88 mm. The built-in lithium battery enables field operation without external power connection, making it ideal for remote or off-grid testing scenarios. Despite its compact size, the KDJB-650S delivers substantial output power: >85 VA per phase for current (6×20A mode) and >48 VA per phase for voltage (6×130V mode). This compares favorably with units such as the 16.8 kg Omicron CMC 356, which is substantially heavier and less portable for field use.
The KDJB-650S provides comprehensive GOOSE and digital substation capabilities:
Four pairs of LC fiber Ethernet ports (one pair Gigabit) for IEC61850-9-2 and GOOSE communication
Four ST fiber serial ports for IEC60044-8 (FT3) and IRIG-B synchronization
Two RJ45 Ethernet ports for MMS and TCP/IP communication
Built-in GPS/BeiDou with IRIG-B output and IEEE 1588 support for precise time synchronization
SV and GOOSE packet analysis with SCD/CID file comparison and one-key consistency verification
Cloud testing functionality with remote configuration and automatic report generation
8 binary inputs (20–250VDC, electrical isolation) and 6 binary outputs (1–4 standard with <2ms response; 5–6 fast with <100µs response)
Distortion, overload, short-circuit, and open-circuit hardware-based protection with alarm
9-inch capacitive touchscreen (Linux OS) plus PC remote control capability
4G (optional), WiFi, Bluetooth, USB interface
Wireless phase identification via LoRa (optional) and 8-channel analog low-level signal output (optional)
Auto-generated PDF/CSV reports via USB
SCD file graphical display and CID file online verification
The KDJB-650S is strategically priced in the mid-range segment, offering exceptional value. While global market data indicates the average selling price for digital relay protection testers is approximately US$5,200 per unit (2025 average), this figure includes a broad range of configurations from entry-level to high-end.
While OMICRON’s CMC 356 typically commands a premium price well over US$50,000, GFUVE’s TEST-630 is priced at approximately US$37,000, and ONLLY units fall in the US$12,000–18,000 range. The KDJB-650S is offered at a more competitive price point, typically ranging from US$8,000 to US$12,000, making it one of the most cost-effective handheld GOOSE-capable relay testers on the market today.
Comparative Pricing Summary Table:
| Model | Approximate Price (USD) |
|---|---|
| OMICRON CMC 356 | $50,000–60,000 |
| Doble F6150sv | $40,000–50,000 |
| Megger SMRT410D | $25,000–40,000 |
| Beijing GFUVE TEST-630 | $37,000 |
| PONOVO POM2-3333 | $15,000–22,000 |
| ONLLY-F08A | $12,000–18,000 |
| KDJB-650S | $8,000–12,000 |
All prices are approximate and subject to configuration and regional variations.
4. Comprehensive Specification Comparison
| Feature | KDJB-650S | OMICRON CMC 356 | Doble F6150sv | Megger SMRT410D | ONLLY-F08A | PONOVO POM2-3333 |
|---|---|---|---|---|---|---|
| Current Output | 6×20A / 3×40A | 6×32A / 3×64A | 6×35A (opt.) | 6×30A | — | — |
| Voltage Output | 6×130V | 4×300V | — | 4×300V | — | — |
| Voltage Accuracy | <0.08%rd+0.02%rg | High | High | High | — | 0.05% |
| Frequency | 10–1000Hz | 10–1000Hz | — | — | — | — |
| Phase Accuracy | ±0.1° (typ.) / ±0.2° (guar.) | ±0.1° | — | — | — | — |
| GOOSE Support | Yes (multi-pair) | Yes | Yes (opt.) | Yes (opt.) | Yes | Yes |
| SV/IEC60044-8 | Yes | Yes (SV) | Yes (SV, 3 streams, opt.) | Yes (SV) | Yes | Yes |
| Wireless | WiFi/BT/4G (opt.) | WiFi opt. | WiFi opt. | — | WiFi | — |
| Screen | 9" capacitive touch | — | Front-panel display | Touch (STVI) | — | — |
| Sync | GPS/BD, IRIG-B, 1588 | GPS/IRIG-B | GPS | GPS | GPS/IRIG-B/1588 | GPS/IRIG-B/PPS |
| Weight | <4.5 kg | 16.8 kg | — | Compact | — | 14 kg |
| Dimensions (W×H×D) | 278×191×88 mm | 450×145×390 mm | — | — | — | 390×210×287 mm |
| Analog Small Output | 8 ch (opt.) | — | 12 ch | — | — | — |
| Approx. Price (USD) | $8k–12k | $50k–60k | $40k–50k | $25k–40k | $12k–18k | $15k–22k |
Oversea Sales Manager
