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
.
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.
