ABB ETL600, Instruction Manual

Page: 164 / 382

ABB Switzerland Ltd
1KHW001489-EN ETL600
associated weights are given in Table 5-1 on page 5-8. The following
relation holds between a weight and the associated system level:
) log( 20 ) ( 0 weight PEP dBm
× =
The difference between dBm (PEP) levels and dBm0 levels is called
relative level and expressed in dBr as explained in section 5.2.8. In the
configuration text generated by the HMI600, the relative level is given
for each configured teleoperation in- and output-port. The sum of the
weightings of all signals to be transmitted by the ETL600, called the S-
value, is also given in the configuration text. Refer to section 5.2.11 for
more information about the S-value.
5.3.4.3. Configure teleoperation port not used for transit operation
From menu
Configuration
click ‘
Configuration / Teleoperation, ext.
teleprotection
’
Switch a port on:
1. Select the port you want to configure.
2. If the service(s), which run(s) over the port, can be interrupted
when a teleprotection command is transmitted or received locally:
Click
On – disconnectable
.
In case the service mustn’t be interrupted by a teleprotection
command, click
On - non disconnectable
.
3. Activate
Squelch at SNR alarm
, if the output of port should be
muted in case of low signal to noise ratio. Typically the squelch
function is activated for modem applications.
The signal to noise ratio is calculated in the pilot channel. The limit
for activating the link alarm and for squelching the AF ports can be
configured in
Configuration / System / Alarm settings
.
Configure input level:
From the sheet
Configure Teleoperation, ext. teleprotection
’ click:
4. Specify signal.
5. Select the correct
‘Reference signal’
. Normally this is given by
external device connected to the port.
6. Select the correct
‘Input level’
for the signal, which in the
configuration printout appears as 'Reference signal level input'. It is
the output level of the external device. Recommended values are –
6.0 dBm or less.
7. Select either the unit
dBm (RMS)
or
dBm (PEP)
. In the HMI600,
the peak to average ratio for many signal types are stored.
If you are not sure, you should select dBm (RMS).
Note:
For non transit application, it is normally not
necessary to check additional signals in the list
‘
Signals after selected filter
’ of the ‘
Input
’ sheet!
Configure output level:
8. Click
Next
to configure the output port characteristics.
5-20 November 2005 Configuration and Set-up