Advanced Energy RFG 1251, Руководство пользователя

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4-2 Connectors, Indicators, and Controls 5706058-A
Advanced Energy
®
Table 4-1. User Port Signals
Analog Outputs The analog readback signals from the generator (pins 2 and 3)
are driven by precision, low-offset operational amplifiers
(industry type OP200GP). These devices are capable of driving
high-capacitance loads such as those expected in shielded
interface applications. The user’s receiver must present a 10 k
Ω
(or greater) impedance to these signals. The readback signals,
which represent the forward and reflected power as measured at
the output of the generator, are scaled as defined in Table 4-2.
Analog Inputs The setpoint signal from the user (pin 5) is a 0 to 10 V signal
scaled to represent the desired power from the generator (refer to
the signal description table for details). The driver circuit must
be capable of operating into a high capacitance load condition
(cable capacitance plus 1000 pF at the EMI filter in the
generator).
Digital Outputs The status signals provided by the generator (pins 14, 20, 22, 24,
and 12) are opto-coupled with NPN transistor outputs (industry
type 4N37). The collector and emitter of each transistor are
provided to the user interface. Each transistor can provide a
minimum of 8 mA of collector current and may be operated with
a collector-to-emitter voltage of up to 30 V. Refer to Table 4-2
for signal definitions.
Digital Input The RF PWR ON control signal (pin 4) is opto-coupled (industry
type 4N37). The user’s signal drives the LED in the opto-coupler
through a 510
Ω
resistor. A signal level of 4 to 30 V applied to
pin 4 enables the RF power.
Interlock The interlock signals (pins 10 and 23) provide the dc power to
close the ac contactor in the generator. Pin 10 is tied to the
generator’s +24 to 30 V through a current limiting circuit. Pin 23
is series wired with the interlock switch on the RF output
connector and then tied to the contactor coil driver circuit.
Connecting pin 10 to pin 23 closes the contactor, enabling ac
power to the RF circuits.