Advanced Energy Paramount MF 2 kW, Руководство пользователя

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At RF on, the generator starts at predefined frequency (start frequency) and waits a
predefined amount of time (tuning delay) to let the process to stabilize. Actual initial
delay is:
t = Tuning delay + 10 ms
After the initial delay, the generator starts to adjust the frequency to minimize the
parameter D. The target for D is the low tuning threshold (which can be numbers
between 0 and the high tuning threshold).
The tuning process may result in one of four outcomes:
• The generator continues adjusting the frequency until the D magnitude falls
below the low tuning threshold. When the low tuning threshold is reached,
tuning stops.
• If the generator cannot reach the low tuning threshold before the tune time
exceeds the tuning timeout, and maximum tuning count isn’t reached, the
generator delivers error code
200 , Unable to Tune, and turns RF off.
• If the generator cannot reach the low tuning threshold and it exceeds maximum
tuning count before exceeding the tuning timeout, the target for the D changes
to the high tuning threshold. Now the generator continues to adjust the
frequency until the D magnitude falls below the high tuning threshold. When
the high tuning threshold is reached, tuning stops.
• If the generator can’t reach the high tuning threshold and the tune time exceeds
the tuning time-out, the generator delivers error code 200 , Unable to Tune.
We recommend a very low value for the low tuning threshold and a very high value
for the high tuning threshold. In most cases, tuning trajectory never reaches the low
tuning threshold and always crosses the high tuning threshold. As a result, the unit
cannot reach the low tuning threshold and keeps tuning near the optimal point until it
reaches the maximum tuning count. When the maximum tuning count is reached,
tuning stops at this point because it is already below the high tuning threshold.
RETUNING
As a process continues with RF on, conditions can change, and the changing
conditions can affect the load impedance and the value of D.
If tuning was just stopped, D = D_tuned and frequency is constant. Now, if because
of a process change parameter D increases above the value:
D_retune = D Retuning threshold
then, the generator starts the retuning process. The retuning process also starts if D
increases above the high tuning threshold.
The retuning algorithm works exactly the same way as for RF ON tuning, except
there is no initial tuning delay. Also, if the generator is already tuned, and command
for sweep frequency tuning mode is sent, the generator goes to the start frequency
and starts the automatic tuning process from the beginning.
Advanced Energy
®
Paramount
®
MF 2 kW Generator
57020114-00E Installation, Setup, and Operation 5‑24