D*AP4 VAP
85
Technical Data -
GPI wiring
The device offers a unique circuitry to save
GPI
setups from hum and noise influence in complex
installations. Here the principle circuit of one of the
eight GPI
inputs:
At the
GPI
input is a
bridge rectifier
I.e. you do
not
need to care about the polarity of the input voltage.
A
constant
current source
in line with the
optical coupler
limits the current.
You must simply provide a voltage in the range from 5V to 30V to activate a
GPI
.
If you have open collector outputs or simple relay closures as the driving
GPOs
(this technique is commonly
known as "low active" and will be found in most legacy equipment),
you must wire up an auxiliary voltage supply.
The device provides such auxiliary power supply. It offers a balanced 5V source that you can imaging
as a battery.
Here an example how to wire up GPI #4:
We strongly recommend to spent a wire for ground connection instead of using the chassis common grounds
of an installation.
GPI
common
GPI_x
5 V balanced
13
24
25
1
GPI 1, 2, 3, 4
common
GPI 1
2
GPI 4
5
GPO
relay or open collector
25 pin GPI/O connector
