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DEWE-ORION-0824-20x
The signal from the 5-pin Molex connector is also available on the analog input connector an can be used for
hardware synchronisation of 3rd party measurement hardware.
EXT_CLK
DIV_EXT_CLK2
1
+5 V
GND
2
3
4
5
Type: 5-pin CON6 connector
(MOLEX KK
®
series)
GND
2.4 Analog signals
All 8 channels of the DEWE-ORION-0824-20x are fully differential inputs with 1 MOhm differential input
resistance and each input with 60 pF to GND. But the inputs are setable via software to single-ended inputs
where the minus input will be switched to GND. Then also two highpass filters with 0.15 and 3.4 Hz corner
frequency are selectable. The input voltage range is selectable in 4 ranges with 0.1 V, 0.5 V, 2V and 10V.
Because of the differential input structure, the difference of the input (Channel xx (+) - Channel xx (-)) will be
shown as the result of the measurement. Although the input is protected for input voltages up to ±30 V, the
common voltage range of each input is limited to ±10.5 V. If the input voltage exceeds this range, the result is
not valid even when the difference input voltage is lower than 10 V. These voltage ranges will be clipped and
introduced as large errors that can be easily identified in the frequency spectrum.
Examples:
V(+) = +10 V, V(-) = +5 V, voltage difference = 5 V, result is valid
V(+) = +15 V, V(-) = +10 V, voltage difference = 5 V, result is not valid (V+ will be clipped at +10.5 V!)
The differential input is ideal for grounded signal sources because the ground loop between signal
source and input is eliminated automatically. When measuring floating input sources (batteries or isolated
thermocouples) it is necessary to select the single-ended input structure by software.
DEWE-ORION-0824
Floating source
CH. X +
CH. X -
Connection to analog GND
Twisted pair
cable
single-ended inputs
DEWE-ORION-0824
Grounded source
Twisted pair
cable
CH. X +
CH. X -
Differential inputs
If you use a customized cable for signal connection, we strongly recommend to use twisted pair cables.
Each channel has to get its own twisted pair. Otherwise the high channel to channel isolation (channel cross
talk) get lost. Also the high signal to noise ratio of up to 108 dB can only be guaranteed by using a shielded
twisted pair cable to connect the signal sources to the DEWE-ORION-0824-20x.
Содержание DEWE-ORION-0824-20 Series
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