NPI SEC-05LX, Operating Instructions Manual

Page: 26 / 69

22
CONTROLS AND
CONNECTORS
FRONT PANEL
ELEMENTS
1 POWER POWER switch
This switch turns on the power supply. The line
fuse, line voltage selector and power cable
connector are located on the rear panel.
2 VC ERROR VC ERROR display
This analog display shows the error in the VC
(voltage clamp) mode (command minus recorded
potential). The desired range of operation is
around zero.
3 INTEGRATOR TIME CONSTANT INTEGRATOR TIME CONSTANT
control and "on/off" switch
· If the control is turned clockwise the
INTEGRATOR part of the PI (proportional-
integral) control is turned on.
· The VC controller then has a PI characteristic
(proportional and integral), which reduces the
error considerably (theoretically to zero).
· The time constant of the integrator is set with
the potentiometer
3.
· Clockwise: time constant is decreased, effect
of integrator is increased.
· When using the integrator, step commands
applied to the
VOLTAGE COMMAND
INPUT BNCs (30 / 32) can cause
overshoots, which can be reduced with the
RISE TIME control 24 .
4 POTENTIAL FILTER POTENTIAL FILTER switch
(20Hz – 20 kHz, 16 position rotary switch)
·
2 pole or 4-pole tunable Bessel filter (12 or 24
dB/octave) with 16 corner frequencies for the
POTENTIAL OUTPUT (see also
CURRENT
FILTER 8.
· The following 16 frequencies can be set:
20, 50, 100, 200, 300, 500, 700, 1k, 1.3k, 2k,
3k, 5k, 8k, 10k, 13k, 20k (Hz)
· The position of this switch is monitored at
the
FREQUENCY MONITOR BNC 25
(-8...+7 Volt, 1 Volt / switch position).