Appendix C: Digital Output & Digital Inputs
21 (24)
C
Digital Output & Digital Inputs
Fig. 10
Current scheme of the main connector
Characteristic
Value
Type of digital output
2
Open drain MOSFET
Maximum current (ext,source)
200 mA
Isolation (both DI & DO)
1.5 kV
DI voltage range
0 to 24 VDC
DI protection
33 VDC Max
DI OFF state — input voltage range
0 to 5 VDC
DI ON state — input voltage range
10 to 30 VDC
DI ON state — current range
From 3,8 mA @ 12 VDC to 8,2 mA @ 24 VDC
The Digital Output is activated by an open drain MOSFET transistor driven by an optocoupler. The
maximum current flow inside this transistor has a value above the one specified in the Cosy+, in
order to cope with the switching power losses.
The transistor used is in an open drain type with predrive. This means the relay power supply has
to be supplied from an external source to the predrive electronics.
The diagram below shows the external wiring needed for proper operation of the digital output.
A relay has been chosen for this sample application but any load within the specifications can be
used instead.
This is a sink only output to ground (the transistor acts as a switch ground).
Ewon Cosy+ Installation Guide
IG-0031-00 1.0 en-US
2.
During the starting boot process, the DO will be switched ON for a short time (2 seconds)