Preventive Maintenance

Overview

The following protective measures should be performed between major system checks, to help maintain the system and protect it against irrecoverable hardware or software with detected failures:

• Continuously review operating statistics

• Save LTMT main unit parameter configuration settings to a backup file.

• Maintain the LTMT main unit operating environment. For more information, refer to the TeSys Tera Motor Management System - Catalog.

• Periodically perform a LTMT main unit self test.

• Check the LTMT main unit internal clock to ensure accuracy.

Statistics

The LTMT main unit collects the following types of information:

• Real-time voltage, current, power, temperature, and I/O data.

• Count of the number of trips, by trip type, that occurred since last power-up.

• Time-stamped history of the state of the LTMT main unit (displaying measures of voltage, current, power, and temperature) at the moment that each of the previous 20 trips occurred.

Use either the DTM or the LTMTCUF control operator unit to access and review these statistics. Analyze this information to determine whether the actual record of operations indicates a problem.

Configuration Settings

In the event of irrecoverable LTMT main unit error detection, you can quickly restore configuration settings if you have saved these settings to a file. When the LTMT main unit is first configured, and every subsequent time any configuration settings are changed, use the TeSys Tera DTM to save the parameter settings to a file.

To save a configuration file:

• Select File > Save As....

To restore the saved configuration file:

1. Open the saved file: Select File > Open (then navigate to the file).

2. Download the configuration to the new LTMT main unit.

3. Select Communication > Store to Device.

Environment

Like any other electronic device, the TeSys Tera system is affected by its physical environment. Provides an environment by taking common-sense preventive measures, including:

• Scheduling periodic examinations of battery packs, fuses, power strips, batteries, surge suppressors, and power supplies.

• Keeping the TeSys Tera system, the panel, and all devices clean. An unobstructed flow of air will prevent dust build-up, which can lead to a short-circuit condition.

• Remaining alert to the possibility of other equipment producing electromagnetic radiation. Be sure no other devices cause electromagnetic interference with the TeSys Tera system.

Self Test Without Trip

Press Reset button for 3 to 15 seconds to perform a self test without trip. When the button is released, the LTMT main unit LEDs will turn ON in pattern1 for 1 second. After 1 second, the LTMT main unit LEDs will turn ON in pattern2 for 1 second. After 2 seconds from the beginning of the test, LTMT main unit comes out of the test mode.

The graphical representation of self test mode without trip is as follows:

Self Test With Trip (If Motor is Stopped)

When a self test with trip command is received from LTMTCUF control operator unit or communication network or a digital input of the LTMT main unit:

• The LTMT main unit LEDs will turn ON in pattern1 for 1 s. After 1 s, the LTMT main unit LEDs will turn ON in pattern 2 for 1 s

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• The state of the trip digital output changes for 2 s

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• After 2 s from the beginning of the test, the LTMT main unit comes out of the test mode, and the state of the trip digital output will change.

The graphical representation of self test mode with trip is as follows:

Internal Clock

For accurate record of trips, the LTMT main unit internal clock must be synchronized regularly. The LTMT main unit time stamps all events, using the value stored in the Date And Time Setting parameter.

The date and time can be set in the LTMT main unit by using:

• TeSys Tera DTM

• LTMTCUF control operator unit

• Communication network

Internal clock accuracy is +/-1 s per hour. If power is continuously applied for one year, the internal clock accuracy is +/-30 m per year.

If power is turned Off for 12 hours or less, the LTMT main unit retains its internal clock settings, with accuracy of +/- 2 m.

If power is turned Off for more than 12 hours, the LTMT main unit resets its internal clock to the default time.