Denkovi DAEnetIP4 User Manual page 16

Figure 13. How the power supply cable must looks like
Additionally, you can check if the supply adaptor has this sign:
Figure 14. The power supply must be marked with this sign
DAEnetIP4 12 Relay Module has protection against reverse polarity
which is actually diode in parallel of the supply jack but it is still not
recommended to reverse the voltage polarity!
DAEnetIP4 12 Relay Module does not accept AC supply voltage. It is
highly recommended to check the power supply source parameters before
turning on the module.
The power supply equipment shall be resistant to short circuit and
overload in secondary circuit.
When in use, do not place the equipment so that it is difficult to disconnect
the device from the power supply.
7.3. Network connection
DAEnetIP4 12 Relay Module supports AUTO-MDIX so either "crossover" or
"straight-through" network cable can be used.
GND
(NEGATIVE)
+VCC
+
-
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