Lambda 303 Series, Operator'S Manual

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INSTALLATION
4-14
If the power supply was purchased with the 400VAC input configuration, in
addition to the three phases, the neutral wire must be connected to
terminal marked N. Failure to connect the Neutral wire in a 400VAC unit
may result in damage to the supply. Neutral current is 2A or less.
RECCOMENDED AC INPUT CABLE SIZE
AC INPUT
VOLTAGE
MODE
MODEL 203 MODEL 303
Cap Charging 5 AWG 4 AWG
432-528 VAC,
50-60 Hz, 3
φ
Continuous DC 4 AWG 3 AWG
Cap Charging 5 AWG 4 AWG
360-440 VAC,
50-60 Hz, 3
φ
Continuous DC 4 AWG 3 AWG
Cap Charging 3 AWG Not Available
180-264 VAC,
50-60 Hz, 3 φ
Continuous DC 3 AWG Not Available
Table 4-1 Recommended AC Input Cable
The AC input rating is marked on the rear terminal of the power supply. The rating is
also part of the unit’s model description shown in Table 1-1.
4.6 CONNECTING THE HIGH VOLTAGE OUTPUT
Ensure that the power supply is off and disconnected
from the AC input power and that all load capacitors are
discharged and shorted to ground before making any
connections. Never handle the HV cable while the supply
is operating. Never operate the supply without a load
capacitor connected.
Always use the HV connector and cable provided with the power supply or an equivalent
substitute provided by Lambda Americas. Fully insert the connector end of the HV cable
and tighten the locking nut only "hand tight".
When operating above 20kV and 200Hz rep rate a silicone grease (such as Dow Corn-
ing DC-4) must be applied to the HV cable before insertion into the HV connector. The
grease is used to displace air in the connector and reduce long-term corona effects. A
cable greasing procedure is available for download from the Lambda Americas web site.
The load ground must be connected to the chassis ground through a separate safety
ground cable with a suggested minimum wire size of 6 AWG in addition to the H.V. out-
put cable shield (see Figure 4-4).
Some peak current will flow out of the power supply during discharge and return through
the HV return and system chassis. This current comes from voltage reversal in under-
damped systems and from normal discharge of filter and cable capacitance. The path
for this current should not parallel control signal returns since the resulting voltages