GE Multilin EPM 9900P Power Quality Instrument Debugging and Fault Diagnosis Guide

Flicker: IEC 61000-4-15 Class A certified, supports 50Hz and 60Hz systems.

Voltage dip/rise, interruption, rapid voltage change: recorded in half cycle RMS.

Transient overvoltage: 50MHz sampling rate, capable of capturing nanosecond level spikes.

3.3 Waveform and Fault Recording

16 bit A/D, 1024 samples per cycle, providing precise waveform resolution.

Fault recording: Equipped with 8 times full range over range capability (e.g. 5A input can record ± 80A peak value).

Hardware and software triggering: Voltage/current thresholds, rate of change, digital input status changes, etc. can be set.

Transient recording (software option C): up to 50MHz sampling, customizable storage capacity allocation.

3.4 Integration of IEC 61850 and GOOSE Cross Triggering

Software option B and above support embedded IEC 61850 servers:

Supports up to 6 MMS clients simultaneously.

GOOSE publish/subscribe: Supports waveform capture triggered by GOOSE messages to achieve synchronous analysis of station events.

Cross trigger delay<200 microseconds (typical value): enables fault analysis of multiple intervals within the substation.

Support buffered/non buffered reporting and file transfer (such as COMTRADE files).

3.5 Security and Event Logs

Level 9 password protection: Different user levels can authorize different operations (such as configuring TOU, viewing data, resetting, etc.).

System event log: records parameter changes, password access, time synchronization, power on/off, firmware upgrades, etc. for auditing purposes.

On site Configuration and Debugging Guide

4.1 Initial Settings

Power connection: Connect the corresponding voltage according to the ordered control power option (HI, AC, or LD). Note that the HI option supports AC or DC, with automatic polarity recognition.

Voltage/current input: Connect PT and CT according to the wiring diagram (4-wire Y/3 element, 3-wire Delta, etc.). Voltage input can withstand 2500V isolation.

Important: If using line monitoring (as reported in EN 50160), the load must not exceed 250W/channel, otherwise the monitoring must be turned off or an external terminal resistor must be used.

Communication configuration: Set the IP address, subnet mask, and protocol (Modbus/DNP/IEC 61850) through the front panel touch screen or web interface.

CT/PT ratio: Enter the rated value of the primary side in the "System Setup".

4.2 Software Options Upgrade

EPM 9900P allows software authorization upgrade function after installation:

Options Memory Sampling Rate Additional Features

A 512 MB 512 point/cycle basic measurement

B 1 GB 1024 points/cycle IEC 61850 server

C 4 GB 1024 points/cycle IEC 61850+GOOSE+50MHz transient

Upgrade method: Purchase the corresponding upgrade authorization (such as PL9900P-ACC-SAB, SAC, SBC), connect the instrument through EnerVista Launchpad, upload the authorization file, and perform a restart.

4.3 Using GE communicator software

The GE communicator supports connecting remote instruments via serial port, Ethernet, or modem. Main functions:

Real time viewing of voltage, current, power, harmonic spectrum, and phasor diagram.

Configure instrument parameters and save them to a file.

Download waveform files (in COMTRADE or PQDIF format) for use with third-party analysis software such as MATLAB and PowerLogic.

Connection troubleshooting: If a connection cannot be established, check:

Communication cable (RS485 terminal resistor, Ethernet twisted pair).

Is the instrument communication port enabled (some ports can be disabled through the web).

Is the firewall blocking Modbus TCP port 502 or IEC 61850 port 102.

4.4 Transient Recording and GOOSE Trigger Configuration

Set transient recording parameters: In the "Transient Recorder" menu, select the sampling rate (up to 50MHz) and storage depth (any part of 4GB of memory can be allocated).

Configure GOOSE subscription: In the IEC 61850 settings, import the SCL file (CID) and define the GOOSE dataset that needs to be subscribed to.

Association trigger: Map the received GOOSE status input (such as protection action signal) to the trigger source captured by the waveform.

Verification: Use GOOSE emulator to send test messages and confirm that the instrument can generate waveform files and store them.

Common troubleshooting table

Possible causes and solutions for the fault phenomenon

The instrument has no display, the touch screen is black, the control power supply is missing, there is an internal power supply fault, and the fuse is blown. Measure the terminal voltage of the control power supply (HI: 100-240V AC/DC; LD: 18-60V DC). Check the internal fuse (to be returned to the factory).

Display "Voltage Sag/Swell" false positive PT wiring error, voltage threshold setting too sensitive, check PT secondary voltage phase and amplitude. Enter the "Limits" menu and adjust the temporary decrease/increase threshold and hysteresis value.

The electrical energy reading is significantly higher or lower, and the CT/PT ratio setting is incorrect; Improper compensation coefficient check for CT ratio and PT ratio in "System Setup". Confirm whether the transformer loss compensation has been mistakenly activated.