eDAQ PowerChrom 280, Руководство пользователя

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16 PowerChrom
Injection Signal Input
The injection signal input uses a solid-state relay input to recognize
external relay closures. A closure of 10 ms or more results in the
registering of the injection signal with the PowerChrom program. The
input can also be connected to a logic or voltage level output of
another instrument provided the device can sink several milliamperes of
current. The equivalent circuit of the injector signal input (TRIG) is
shown in
Figure 2–6 .
Digital Outputs
There are four digital control outputs (marked CTL1, CTL2, CTL3, and
CTL4), each of which provide a logic level or contact closure
depending on the presence, or absence, of the corresponding links to
Gain
control
900 Hz low-
pass filter
Channel control bus
Detector
To
multiplexer
Grounding
and input
selection
Gain
control
Instrument
amplifier
+
–
+
–
GND
Shielded
cable
Do NOT ground the
shield at both ends!
1 MΩ
COM
+5V
820 R
Internal circuitry
Injection
signal input Injection signal input
(contact closure)
+5 V
820 Ω
Internal circuitry
TRIG +
TRIG –
Figure 2–5
Block/schematic
diagram of the input
amplifier circuitry.
Figure 2–6
The equivalent circuit of
the injection signal input.