Hardware description
Chapter 2.
(*) when the eWON COSY reboots, a short phase of ON state is part of the starting process.
The digital output is activated by an open drain MOSFET transistor driven by an optocoupler. The
maximum current flow into this transistor has a characteristic above the value specified in the
eWON, 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 correct
operation of the digital output. A relay has been chosen for this sample application but any load
within the specifications can be used instead.
Note
: this is a sink only output to ground (the transistor acts like a switch to ground).
eWON COSY 141 - Installation Guide (How to)
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