Lambda 303 Series, Руководство оператора

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CONTROLS, INDICATORS, CONNECTORS
83-489-009 Rev A
5-3
The END OF CHARGE indicator will illuminate when the load capacitor is charged to the
programmed output voltage. The END OF CHARGE indicator will be extinguished when
the high voltage is OFF or during load charging. End Of Charge may illuminate if the
output voltage is programmed to zero.
5.2.1.5 AUTO DWELL (Normally OFF)
The AUTO DWELL (also known as Autoinhibit) feature shuts OFF or inhibits the output
current when the capacitive load is discharged. This feature allows the HV switch in the
external load circuit to better recover after the load switching event.
The AUTO DWELL feature overcomes the need for the external inhibit signal in most
cases. The AUTO DWELL circuit automatically creates an internal inhibit of approxi-
mately 1 ms after the circuit detects high dv/dt at the output. The AUTO DWELL period
can be programmed via a 0-10 VDC signal applied to the AUTO DWELL input on the
rear panel remote interface connector. 0V input gives an Auto Dwell period of approxi-
mately 500
μ
s, 10V gives an Auto Dwell period of 5ms.
The AUTO DWELL circuit will only work (detect a discharge) when the discharge occurs
from between 20% to 100% of the full output voltage rating of the power supply. If a dis-
charge occurs from less than 20% of the rated voltage the circuit will not generate an in-
ternal inhibit and the power supply will continue to deliver output current.
5.2.1.6 INTERLOCK CLOSED (Normally ON)
This indicator is illuminated when the external interlock circuit is closed. The 4 position
barrier strip interlock terminals located on the rear panel (see Figure 4-2) must be
shorted to allow the supply to operate. These terminals may be run through any number
of contacts for personnel and system safety. INTERLOCK CLOSED is the inverted sig-
nal of interlock open included in the INPUT POWER status LEDs. If the interlock circuit
is not closed, the main AC power contactor cannot close, AC power cannot be applied to
the HV power generating circuitry and the power supply will not operate.
The INTERLOCK circuit also runs through a safety switch located under the top cover
that opens if the top cover is removed, again preventing closure of the AC contactor.
5.2.2 HV Status LEDs
5.2.2.1 EXCESS REVERSAL (Normally OFF)
This indicator will illuminate if excess voltage reversal is detected at the HV output. A
large reversal would cause damage to the power supply by drawing too much current
through the output diode rectifiers. While the EXCESS REVERSAL sense circuit does
not directly protect the diodes, it will stop the power supply from continuing to run in the
case where reversal may be building up and could cause damage if left unchecked.
This protection circuit will reset automatically after three (3) seconds and restart the
power supply. Repeated operation of this circuit indicates the presence of a persistent
problem that must be corrected by some form of protection, clipper circuit or small series
resistor. Refer to Application Note 517 (available from the factory or at
www.us.tdk-
lambda.com/hp ) for more information.
5.2.2.2 OVERLOAD (Normally OFF)
The OVERLOAD circuit indicates if a short circuit or an extremely large capacitor is in-
advertently connected to the power supply.