Elenos ETG2500, User Manual

Page: 36 / 78

36 Instructions for use
3.1.12.1 Power oscillation algorithm
In Elenos devices, if there is a power variation of “n” W (“n” being defined in specific
tables) at least 3 consecutive times within 15 seconds, the “035” alarm is activated and
the three block out mechanism is triggered (if this mechanism fails, the “003” alarm is
then activated).
3.1.12.2 Foldback algorithm
The Elenos devices feature two different and independent protections which are activa-
ted when there is an excess of reflected power.
The first is a hardware threshold which operates when the reflected power exceeds
10% of the maximum rated output power of the transmitter in a very short space of
time.
In these conditions the transmitter switches off.
The second is a software protection, called “foldback algorithm”.
It is activated when the reflected power increase is slower (for example, when there is
snow or ice on the antenna).
In these conditions, the transmitter gradually reduces its output power until the reflec-
ted power threshold is exceeded, while the output power is gradually restored when
the values go back to normal.
If normal operating conditions continue for more than 60 seconds, the algorithm is
inactive.
The activation of this second protection is left to the user (from the System config scre-
en).
3.1.12 System config
Setting and display screen.
The following parameters can be set by the user: temperature measurement unit
(Temp. U.), remote display operating mode (Show D.), audio board model (BB model,
automatically detected, or STEREO view as default), equipment protection in case of
oscillations (PwOscChk), power target when working with a UPS (UPS T), VCO synchroni-
zation (Time base, internal or external
at 10MHz), power reading calibration (FwdPwrCal), SWR foldback, polarization threshold
(IPA Bias Tres.), reflected power nominal threshold (Refl.Pwr T.N., when active it is
10% of direct power), reflected power customized threshold (Refl.Pwr T.Lev., when the
nominal threshold is inactive, it is possible to set values below10%), final polarization
(PAbias), maximum settable power full scale (Max Target Pwr).