400 Series Installation and Configuration
DCU 410 Engine Panel Installation
17
The state of each channel is controlled by the voltage
between the +24V switch input terminal (terminals 17-
24) and the +0V opto terminal (terminal 25) as follows:
0
–
2V = logic
“0”
8
–
32V = logic
“1”
2
–
8V = undefined, avoid this area.
Further switch input details
Overvoltage protection: 40 VDC
Not connected = 0V (47 kohm pull-down).
The 24VDC on terminal 16 shall be used for the switch
input supply. It is secured with a 40 mA automatic fuse.
Normal Use
Terminals 25 and 26
shall
be strapped.
Terminals 17 - 24 connected to 24V (terminal 16)
through external switches.
Opto-coupled Use
Terminals 25 and 26 shall
not
be strapped.
External voltage input between terminals 17 - 24 (+24V)
and terminal 25 (0V opto) is electrically isolated from the
DCU by the means of integrated opto-coupled devices.
4-20 mA Input Channels [27
–
31]
There are four configurable 4-20 mA analogue sensor
inputs.
If the signal is out of range, a warning will be displayed.
Out of range is defined as:
<2 mA (broken)
>24 mA (short)
Update rate: 2Hz
PT100 Input Channels [32
–
43]
There are four PT100 input channels. The channels
support PT100 sensors with two or three wires.
Note! If connecting a two-wire PT100 sensor, then strap
the two wire terminals A and B at the DCU end.