Advanced Energy VarioMatch Match Network VM 1000 Platform, Руководство пользователя

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AE VarioMatch
TM
Match Network, VM 1000/1500 P l atform
Cable Requirements
GENERAL CABLING CONSIDERATIONS FOR PLASMA/LOAD
The main objective of an RF delivery system is to provide as much of the generator's
output power to the load as possible. However, losses occur in the coaxial cable, the
match network, and in the lead between the match network and load. These losses
should be kept as low as possib l e.
Guidelines to Minimize Losses
Use the following guidelines to minimize losses:
• Keep RF cabling between matching network and
l oad as short as possible.
• Ensure proper shielding of all RF
l eads .
• Ensure a proper RF return path (ground). Remember that RF can only run on the
surface, b u t not through material.
• All RF conductive parts should consist of silver plated copper, e
l ectrolytic copper,
aluminium, or stainless steel.
• Do not use regular steel because it is a bad RF conductor. It will cause high losses
and eventually burn away.
Guidelines for PLASMA/LOAD Cables and Connectors
The proper connec t ion of the VarioMatch match network to the load influences
operation of the whole RF system. The following is important information for
connecting to
PLASMA/LOAD.
There will be a high RF current flowing between the V arioMatch match network and
the l oad. The RF output
(PLASMA/LOAD)
is much higher than RF input
(RF­
GENERA TOR). High currents are common because the real part of a load
impedance is t ypically be t ween 1 Q and 10
n.
This results in a relatively high current
even at low RF power levels.
Due to skin effects, the RF current will flow only on the surf ace of the conductor,
reaching a depth of on l y 10 micrometers to 20 micrometers , depending on the
conductor material and the frequency. To reduce the conductive l osses as well
unwanted vo l tages drops across the lead, always try to optimize the surface area of a
lead.
The l arge RF current flowing through the l ead to the load will cause l osses in power as
well as RF radiation. For optimum resu l ts , minimize the lead length and maximize the
lead surface area. If you don ' t use a coaxial cab l e as the
PLASMA/LOAD
connection
(coaxia l cable should not be used at power l eve l s exceeding approximate l y 1.5 kW),
you must ensure adequate RF shielding of the connection to prevent RF radiation
which can cause malfunctions in nearby instrumentation and electronic equipment.
57020080-00D
I nstallatio n , Set u p , and Operat i on
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