Ericsson LBI-39128 Alarm Limit RE-CONFIGURATION, SWR Upper Limit, Transmitter Power Alarm Limits

LBI-39128 OPERATION

SWR Upper Limit

This parameter is used by the PMU as the upper alarm limit for each antenna’s SWR. Its purpose is to detect when the antenna or coax to the antenna is damaged. The recommended value for this limit is 2.0, which is equivalent to about 11% reflected power.

This parameter is not programmed into the Site Controller computer’s Personality PROMs and is therefore not re-configurable through a System Manager. The value of this parameter is only contained in the PMU.

A factory default value (2.0) for this parameter has been programmed into the PMU. This factory default is used to configure the PMU’s Active Configuration any time the PMU is Initialized. The value of this parameter may be re- configured with an RS232 CRT terminal connected to the PMU. This re-configuration will last until you deliberately initialize the PMU. This re-configuration permits a different upper alarm limit for each antenna’s SWR.

Antenna Mapping

Antenna Mapping is described under the PMU Programming heading in the Installation section.

Transmitter Power Alarm Limits

The upper and lower alarm limits for each transmitter’s output power may be re-configured as follows:

1.With the Operational Select Menu (main menu) shown on the terminal, type 4 (for item #4 - Setup) and press the Enter key.

2.With the Setup Selection Menu shown on the terminal, type 4 (for item #4 - Analog Input Channel) and press the Enter key.

3.At the “Enter Channel Number” prompt, type the channel number of the transmitter and press the Enter key. The Analog Input Channel screen for that transmitter channel should then appear on the terminal.

4.Type 6 (for item #6 - Lower Alarm Limit) and press the Enter key.

5.At the “Enter New Data” prompt, type the new value and press the Enter key. The screen should then be updated to show the new value. (This is a temporary configuration.)

6.Type 7 (for item #7 - Upper Alarm Limit) and press the Enter key.

ALARM LIMIT RE-CONFIGURATION

Alarm Limits As Installed

As installed per the Installation section, the alarm limits are as follows:

∙Transmitter Upper Power Limit = 125.0 watts

∙Transmitter Lower Power Limit = Determined by the Site Controller computer’s Personality PROMs or the re-configured value with the System Manager.

∙Antenna Upper Power Limit = 999.9 watts

∙Antenna Lower Power Limit = 0.0 watts

∙Antenna Upper SWR Limit = 2.00

These alarm limits may be changed in the PMU’s Active Configuration with a terminal connected to the PMU. See the PMU Programming heading in the Installation section to set up the terminal and obtain programming access.

7.At the “Enter New Data” prompt, type the new value and press the Enter key. The screen should then be updated to show the new value.

8.Type E (to End programming this channel) and press the Enter key. The Setup Selection Menu should then appear on the terminal.

This completes the re-configuration of the Upper and Lower Alarm Limit parameters for the selected transmitter channel number. If this parameter needs to be changed for another transmitter, repeat steps 2 through 8 for that transmitter. (Remember that the lower alarm limits you re- configure here are just temporary. These limits will be re- configured to the single value of this parameter in the Site Controller computer’s Active Configuration each time the Site Controller computer sends the EDACS Configuration Setup to the PMU.)

Antenna Power Alarm Limits

The upper and lower alarm limits for the antenna’s input power may be re-configured as follows:

1.With the Setup Selection Menu shown on the terminal, type 4 (for item #4 - Analog Input Channel) and press the Enter key.

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