The Level-Add logical device provides a simple mechanism to monitor transmit power values in EIRP. The Level-Add device uses a fixed calibration offset. It work like the Level-Set device but only for reading the EIRP.
The Level-Add device monitors a configurable parameter for power measurement and adds a calibration offset to calculate the real transmit EIRP. This in most cases is the antenna gain reduced by the waveguide loss between the measurement point and the antenna.
The device monitors also a minimum and maximum threshold to raise an low or high EIRP fault and optionally the Communication Fault of the power measurement device.
Device window pages
The following table shows which device window pages are available with this individual device type. Tool-bar functions not mentioned here are described at the general description of device windows .
--- This page shows the level calculation.
--- The device info page.
--- The maintenance page. The configuration parameters described below are set at this page.Configuration parameters
At the maintenance page of the device window there are a couple of configuration parameters which must be set to interconnect the Level-Set device to the devices it monitors and controls.
| parameter | description |
|---|---|
| pwrMeasId | The message ID for the output power reading. |
| config.faultId | The message ID to detect and communication fault of the measurement device |
| config.noPwrThreshold | This value defines when the power reading indicates that there is "no power". Helpful for equipment which returns low power reading even if there is no output |
| config.noPwrEirp | This is the return value of measuredEirp if a "no power" condition is detected. Default is -99.99 which was the behavior until driver version 1.06 |
Limit Checking
At the primary device page, min and max threshold values may be defined. These values apply to the measured EIRP. If the measured EIRP exceeds the limit values a low or high EIRP fault is generated. The fault gets cleared if the EIRP value returns inside the limit window or a "no power" condition is detected.
Variables defined by this device driver
| name | type | flags | range |
|---|---|---|---|
| info.driver | TEXT | R/O | StringRange R/O |
| lowLevel.cmd | TEXT | StringRange | |
| lowLevel.reply | TEXT | R/O | StringRange R/O |
| faults.99 | ALARM | R/O | AlarmFlagRange R/O (Communication) |
| faults.commstat | TEXT | R/O | StringRange R/O |
| info.type | TEXT | R/O | StringRange R/O |
| info.port | TEXT | R/O | StringRange R/O |
| info.frame | TEXT | R/O | StringRange R/O |
| config.pwrMeasId | TEXT | SAVE SETUP | StringRange |
| config.faultId | TEXT | SAVE SETUP | StringRange |
| config.noPwrThreshold | FLOAT | SAVE SETUP | DoubleRange (0.00 .. 0.00) |
| config.noPwrEirp | FLOAT | SAVE SETUP | DoubleRange (0.00 .. 0.00) |
| offset | FLOAT | SAVE | DoubleRange (0.00 .. 0.00) |
| measuredEirp | FLOAT | R/O | DoubleRange R/O (0.00 .. 0.00) |
| internal.meas | FLOAT | NOPRESET | DoubleRange (0.00 .. 0.00) |
| internal.flt | BOOLEAN | NOPRESET | BooleanRange (true false) |
| minEirp | FLOAT | SAVE | DoubleRange (0.00 .. 0.00) |
| maxEirp | FLOAT | SAVE | DoubleRange (0.00 .. 0.00) |
| noPower | BOOLEAN | R/O | BooleanRange R/O (true false) |
| faults.01 | ALARM | R/O | AlarmFlagRange R/O (EIRP low threshold) |
| faults.02 | ALARM | R/O | AlarmFlagRange R/O (EIRP high threshold) |
| faults.03 | ALARM | R/O | AlarmFlagRange R/O (Meas.Device Comm.) |