VICI TCD2 - Manual (Page 8)

4
Description of Controls and Connectors
Controls and connectors are indicated in Figures 2 and 4.
MAINS switch (rear panel)
Controls mains (line) voltage to the controller unit. When this switch is
on ( | ), the unit is operational except for the detector filaments (see next
paragraph) and the detector heater will operate if connected.
FILAMENT switch and indicator
Controls power to the detector filaments; when the switch is on, current
passes through the filaments. The indicator will light even if the detector
is not connected to the controller.
DETECTOR TEMPERATURE control and indicator
Sets the temperature (°C) of the detector heater block. The indicator is
steadily on when maximum power is being applied to the heater, steadily
off when no power is applied, and regularly blinking on/off when the set
temperature has been established.
Note that due to the fail-safe mechanism designed into the temperature
controller, the heater will not operate if mains power is applied before the
heater is connected or if the detector is too cold (< 0°C). If the heater is
disconnected with mains on, the unit must first be turned off to restore
control of the heater; if the unit is operated in a very cold environment,
the detector should first be gently warmed without power applied.
The fail-safe mechanism will also act under any condition resulting from loss
of control (
e.g., over-heating, RTD failure, etc.). If proper procedures have
been followed and the controller will not heat the detector, there is cause
to suspect that the fail-safe mechanism has been activated. Consult the
factory or an authorized representative. Note that the maximum temperature
for operation of the TCD2 is 300°C.
FILAMENT TEMPERATURE switch
Separate 10-turn knobs control Filaments A and B. The value displayed
corresponds to temperatures indicated in Figure 3 for nickel/iron filaments.
COARSE ZERO control
Once filament temperature has been applied, the Coarse Zero knob makes
coarse adjustments of the zeroing voltage supplied for establishing the
baseline zero on both the strip chart output and the integrator outputs.
FINE ZERO control
Once coarse adjustments have been made, the Fine Zero control is used to
make fine adjustments in the output signals.
ATTENUATION control
The Attenuation control determines the attenuation of the signal for the chart
output.
RECORDER switch
The Recorder switch selects which signal is directed to the chart output.
The choices are A, B, or A - B (or A minus B, which is conventional
differential operation with the B channel representing the reference.)
The selected output signal is displayed in the LCD display.
Introduction