KEPCO KLR Series User Manual - Manual (Page 14)

1-2
KLR 091313
1.3 OPTIONS
Options are identified by a letter suffix. Unless otherwise noted, options apply equally to stan-
dard and E-Series models, and specifications are not affected.
1.3.1 RAPID OUTPUT DISCHARGE CIRCUIT (RODC) OPTION (R SUFFIX)
The Rapid Output Discharge Circuit (RODC) option (suffix R) is available on all KLR models.
This circuit rapidly discharges the output capacitance, thus significantly reducing response time
to reductions in output voltage.
The circuit consists of a voltage detector that compares the programmed and actual values of
output voltage. The discharge circuit is activated only when the actual voltage exceeds the pro-
grammed value.
Without the RODC circuit, discharge of the total output capacitance (internal and external) is
achieved through a combination of the external load resistance and an internal current sink. For
high load resistance or open circuit conditions at the output, response time (fall time) can vary
from milliseconds to seconds depending upon the magnitude of the high-to-low voltage transi-
tion.
With the RODC option, output fall time is reduced to approximately the same value as rise time,
even with external capacitance equal to 50% of the nominal internal output capacitance. Table
1-1 illustrates the typical performance improvement that can be expected with an open circuit
output.
The RODC circuit will support continuous repetitive discharges from rated model voltage to zero
at rate of up to 1 Hz for the 20V and 40V models, and up to 0.5 Hz for the 75V, 150V and 300V
models. Smaller discharge steps will be supported at higher continuous rates; contact Kepco
Applications Engineering for additional details. The RODC circuit employs protection against
both peak energy and average power overload conditions by disabling only the RODC function
until conditions recover to normal range; unit performance remains otherwise unaffected. Note
that RODC Option units support the TRANsient command (see KLR Developer’s Guide for
details).
1.4 SPECIFICATIONS
Table 1-2 lists the parameters applicable to individual models. Table 1-3 lists general specifica-
tions applicable to all models except where otherwise noted.
TABLE 1-1. RAPID OUTPUT DISCHARGE CIRCUIT IMPROVEMENT IN OUTPUT RESPONSE TIME
KLR Model No.
Nominal Internal Output
Capacitance
(CO)
Test Voltage
Maximum Fall Time @ 1.5 x Co
without RODC with RODC(1)
KLR 20-120-
(2)
13000 µF 20V 675 msec 30 msec
KLR 40-60-
(2)
7280 µF 40V 1460 msec 30 msec
KLR 75-32-
(2)
5600 µF 75V 3690 msec 25 msec
KLR 150-16-
(2)
2200 µF 150V 8940 msec 30 msec
KLR 300-8-
(2)
550 µF 300V 8720 msec 26 msec
(1) Values shown assume that an external capacitance of 1/2 value of CO is connected across the output terminals.
(2) Specifications listed apply to both standard and E Series models.