TDK 500A - Manual (Page 27)

83-493-001 Rev. K
19
Figure 5-3 HV Bias Measurements
5.5 DETERMINING AC LINE CURRENT
IL = Line current
P = Average output power
VL = Line voltage
PF = Power factor (.65 min)
EFF = 0.85
Ex: A 152A operating from 115V – 10% and delivering 1000W average.
A x I
L
5 . 17 9 . 0
) 85 . 0 )( 65 )(. 115 (
1000
= =
When charging very large capacitor banks requiring many seconds or minutes to reach
end-of-charge, the power supply will display a load fault and go into a 50% duty cycle
protection mode. If this feature is defeated and the power supply is allowed to charge for
an extended period, the peak output power, not the average power, must be used to
determine line current. (See Section 5.7).
5.6 CONTINUOUS HV DC OPERATION (CONSTANT VOLTAGE)
The 500A/102A/152A/202A supplies can be used as a constant voltage supply by the
addition of an external filter capacitor. The value of this capacitor will determine the
ripple voltage on the DC output.
) )( )(
max) ( 4 . 1
Fs Co Vo
Po
V
PK PK
= − Δ
Where: Po max = Maximum output power in watts
Vo = Output voltage in volts
Co = Total output capacitance in microfarads
Fs = Lowest switching frequency (40KHz)
When operating as a DC supply care must be taken not to draw more than the J/sec
rating of the unit.
Also, if the filter capacitor is inadvertently shorted, it may ring which can damage the
supply (Section 5.2).
EFF P V
P
I
F L
L
X
=