Anfatec eLockIn 203, Руководство пользователя

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“no signal”
.
C hannel
[ LockIn / Display / Channel ]
In order to change the settings of the four channels, this button realizes the channel
selection. All selections displayed in
Group
,
Type
and
Range
are valid on the selected
channel only.
Group of Displayed Signal
[ LockIn / Display / Group ]
The large amount of possible input signals is organized in
Group s: LIA n, Misc, ADC,
DAC, LIA 1 .
The
Group “Off”
stands for “no group” = “no signal”
.
Signal Source
[ LockIn / Display / Type ]
The
Type
enables the source selection. All types described in 1.2.2 are available on all
four
Channel
s. The
Source
s selected in the first four channels are sent to the first four
D/A outputs at the rear panel. In order to disable one channel,
Off
has to be selected.
Output Scaling
[ LockIn / Display / Range ]
This parameter changes the display sensitivity, but not the measurement sensitivity. If
the real value is bigger than the range, “
-ovld ” will be displayed. Simultaneously, it
changes the scaling for the output amplitude sent to the D/A converters. The chosen
sensitivity is related to the maximum output value of the D/A converter. which is 10 V.
Thus the D/A output is scaled to this display range.
Example: If channel 1 displays the lock-in amplitude R and its
range is set to 1 mV, a detected amplitude R of 1 mV gives an
output value of 10 V at the DA1 (rear panel). If the signal
shrinks to 1 µV, the output at the DA1 is only 10 mV. Because DA1
adds its own noise, its better to reduce the display range as
much as useful to improve the output signal taken from the DA's
at the rear panel.
3.2.4 AUX O
UT
[ L
OCK
I
N
/ O
UT
]
In principle, this option allows to set the values provided at the eight output channels
with 24 bit converters. With this, the implementation of feedback circuits for Kelvin
Probe applications is prepared.
In the current instrument philosophy, the first four channels are always scaled with the
display settings four the four channels. The AUX outputs AUX5 to AUX8 can be set to a
certain voltage.
AUX Out Cannel
[ LockIn / Out / Channel ]
This option selects the channel out of the eight AUX channels, for which the settings
Type
and
Value
are controlled here.
AUX Out Type
[ LockIn / Out / Type]
Set to
Scaled
, the related channels provides the output with respect to the setting given
in
[ LockIn / Display / Range ]
. Set to
Const.
, a
value
can be set for the
channel.
In the current state, the channels DAC1 to DAC4 are automatically set to
Scaled
, while
the channels DAC5 to DAC8 are set to Const. .
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