Testing an IEC 61850 system takes several kinds of tool: an MMS client that browses the model of each IED and receives its reports, a simulator that publishes GOOSE or emulates a complete IED, a network analyzer that shows what really travels, an SCL file validator and a test set that publishes and subscribes to GOOSE and sampled values while it tests the protection.
Why dedicated tools are needed
In a substation with conventional wiring, a multimeter and a test set are enough to follow a signal from one end to the other. In an IEC 61850 substation the signal is a message: it cannot be measured with a multimeter, it cannot be seen on a terminal block, and it may be present on the network yet be discarded by the device receiving it. Testing it takes tools that speak the protocol, read the system configuration and show what happens on the network.
What has to be observed depends on the service: a GOOSE is checked differently from an MMS report, as explained in GOOSE vs MMS in IEC 61850. No tool does it all. The brands named here are examples; what matters is the type of tool and what it lets you verify.
Types of tool
| Type | What it does | What it lets you verify | Examples |
|---|---|---|---|
| MMS client | Connects to an IED, browses its data model, reserves reports and sends commands | That the IED exposes the expected data, that reports arrive and that commands are accepted or rejected correctly | OMICRON IEDScout; client of Triangle MicroWorks 61850 Test Suite Pro |
| IED or GOOSE simulator | Publishes GOOSE or emulates the complete communication of an IED from its SCL file | The subscriber’s reaction without the real publisher; HMI and gateway integration before all devices are available | IEDScout; simulator of 61850 Test Suite Pro |
| Network analyzer | Captures and decodes traffic | Whether the message exists, with which parameters and timing | Wireshark; manufacturers’ own analyzers |
| SCL validator | Checks the syntax and consistency of the files | Errors in ICD, SCD or CID before loading them | Validators of the engineering tools; SCL viewers |
| Test set with IEC 61850 | Injects currents and voltages, subscribes to the trip GOOSE, publishes GOOSE and, in a digital substation, sampled values | Protection operating times when inputs or outputs are messages | Test sets of the main brands with the IEC 61850 option |
| IEC 61850 network supervision | Continuously compares what is circulating with what the SCD says should circulate | Lost messages, changed configurations, devices that stop publishing | Manufacturers’ diagnostic tools, such as Hitachi Energy ITT600 |
MMS client
It is the most used tool when commissioning the station bus. It shows the model of an IED as loaded, without depending on the HMI, so it can be compared with the specification. With it you reserve a report control block to check which events the device sends, test a select-before-operate command and read the quality of each data item. It also downloads fault records. How MMS works is covered in IEC 61850 MMS.
One precaution: the test client takes up a report control block of the IED. If the HMI or the gateway needs that same block, they will stop receiving data while the test client stays connected.
GOOSE and IED simulator
A simulator reads the SCD and publishes the messages of an IED that is not present, or emulates the MMS response of a complete device. It is useful in three situations: the FAT of an HMI or gateway without all the IEDs, testing a subscriber without its publisher, and extensions, where the part in service cannot be touched. The simulated message must carry the same parameters as the real one; otherwise the subscriber will discard it.
In IEC 61850 Edition 2, simulated messages are flagged with their own bit, and the subscriber only accepts them if it is in simulation mode. That mechanism, and the test mode of the IEDs, are covered in IEC 61850 test and simulation mode.
Network analyzer
The analyzer does not intervene: it only shows. That is why it is the reference when two devices contradict each other. A capture tells whether the GOOSE exists, with which VLAN, APPID, configuration revision and time allowed to live, and whether stNum changes when it should. For MMS it shows associations, reports and retransmissions. Capturing requires a switch mirror port or a TAP, and the clock of the capturing device should be synchronized. All of that is in IEC 61850 traffic in Wireshark.
SCL validator and viewer
Many problems can be caught before going to the field by reviewing the SCD: IEDs without an address, GOOSE without subscribers, subscriptions to data that do not exist, mixed editions. That file is produced by the system configurator, and it is the starting point when there is GOOSE between relays of different brands. You can open an SCD and review its IEDs, subnetworks, GOOSE and SV streams with our free IEC 61850 SCL viewer, with no installation.
Test set with IEC 61850
When the relay trips over GOOSE, as described in protection testing with GOOSE, the test set subscribes to that message and treats it as a binary input: that way it measures the operating time just as with a contact. When the relay expects GOOSE from other devices, the same test set publishes them. In a digital substation it also publishes the sampled values that replace the CT and VT secondaries. Secondary injection remains the basis; what changes is where the signals enter and leave.
Which tool at each stage
- 01EngineeringSCL validator and viewer on the SCD before loading it
- 02FATMMS client and simulator for the HMI and the gateway; test set for the protection
- 03SAT and commissioningMMS client signal by signal, network analyzer and test set with GOOSE
- 04OperationNetwork supervision and analyzer for communication failures
Common mistakes when testing
- Testing with an SCD different from the one loaded. The tool shows what the file says, not what the IED has.
- Forgetting to remove simulation. An IED left in simulation or test mode does not behave as in service.
- Capturing without a mirror port and concluding that the message does not exist.
- Testing only the normal case. Loss of the GOOSE, the rejected command and the link going down must be tested too.
We help you test your IEC 61850 system
At Tiza Group we test IEC 61850 systems at FAT, SAT and commissioning, with test sets, MMS clients and network analyzers, in substations and industry, in Colombia, or elsewhere on request. If the problem is in a relay’s configuration, remote relay configuration corrects it remotely. For testing of the complete system, see FAT and SAT testing.
Related guides
- IEC 61850 traffic in Wireshark: what a capture reveals
- IEC 61850 test and simulation mode
- IEC 61850 GOOSE
- IEC 61850 MMS
- Substation communication network testing
- Standards for commissioning, FAT and SAT testing
- Substation automation system (SAS): functions and levels
- Secondary injection test set: what it is
References
- IEC 61850-10, conformance testing.
- IEC 61850-7-4, logical nodes LPHD and LLN0 (mode and simulation).
- CIGRE, Technical Brochure 401, Functional Testing of IEC 61850 Based Systems, 2009.
- CIGRE, Technical Brochure 760, Test strategy for Protection, Automation and Control (PAC) functions in a fully digital substation based on IEC 61850 applications, 2019.
- OMICRON, IEDScout product information (omicronenergy.com and T&D World articles).
- Triangle MicroWorks, 61850 Test Suite Pro documentation (trianglemicroworks.com).
Frequently asked questions
Is Wireshark enough to test IEC 61850?
To see what travels on the network, yes: it decodes GOOSE, SV and MMS. But it does not publish messages, reserve reports or send commands, and it does not automatically compare what it sees with the SCD. It is complemented by an MMS client and a simulator or test set.
Which tool is needed to test a relay that trips over GOOSE?
A secondary injection test set that subscribes to the relay's trip GOOSE and treats it as one more binary input, to measure the operating time. If the relay also receives GOOSE, the same test set or a simulator publishes the messages the relay expects.
Can the integration be tested without all the IEDs?
Yes. With the SCD file, a simulator can emulate the communication of the missing IEDs, publish their GOOSE and respond as an MMS server. It is useful at the FAT and in extensions, but it does not replace the final test with the real devices.