18
Metal Loss Correction frequency setting
The degree of compensation for metal loss is adjusted with the MLC potentiometer (3).
The start/break frequency is set with the Parametric MLC knee point switch (4) marked:
100Hz, 500Hz, 1kHz, 2kHz.
1. Start with the break frequency set to 2kHz.
2. Adjust the level to -12dB. If this is not sufficient, move to the next lower frequency and
repeat as required.
3. Verify that the loop driver’s voltage doesn’t saturate, i.e. that the peak indicator (8)
only flickers temporarily.
When operating at maximum output on some loop types the automatic limit protection
circuit may cut programme peaks. To rectify, reduce the loop current accordingly.
MLC function in maximum position
0 dB
-5 dB
-10 dB
-15 dB
100
1 kHz
10 kHz
Commissioning and certification
It’s important to check the system when the installation is completed. To ensure that the
loop installation meets the requirements for field strength, consistency and frequency
response, it must comply with the international standard IEC 60118-4.
A guide how to commission a loop system to the IEC performance standard, can be found
in the user guide for the Univox FSM 2.0 field strength meter and in the Univox® Certificate
of Conformity. These documents are also available on www.univox.eu/certify.
