Hydronix Ethernet Adapter, User Manual

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Connecting with Sensors Chapter 2
18 Hydronix Ethernet Adapter User Guide HD0333 Rev 2.1.0
2.1.2 Ethernet Power Adapter connections:
Ethernet Power Adapter Terminal Signal Description
1 0V output
5 24V + output
2.2
RS-485 Wiring Recommendations
The performance and reliability of a RS485 network can depend significantly on the quality
and design of the wiring used. It is recommended to use 24AWG twisted pairs with a
characteristic impedance (Zo) of 100R – 120R. Ideally, sensors on a RS485 network should
be connected in a daisy chain arrangement, as shown here:
This arrangement uses just one of the sets of sensor outputs on the Ethernet Adapter. In
practice, this arrangement is hard to achieve, so sensors may be wired using very short stubs:
Although the Ethernet Adapter has multiple sets of sensor outputs, wiring in a star
configuration with each sensor wired to an output set should be avoided if at all possible.
3 Indicator Lights
The Ethernet Power Adapter unit (EPA01) has a single red indicator light on the top, which
indicates that it is supplying power. It must be connected to an Ethernet cable with an 802.11af
compliant Power Injector supplying it.
The Ethernet Adapter (EA01) has three indicator lights on the top. The red indicator illuminates
when a suitable 24V supply is connected. The transmit indicator light blinks when data is
received by the Adapter and is being sent to the sensors. The receive indicator light blinks when
data is received from the sensors and is being sent over the Ethernet to the host system.
Additionally, the green indicator light above the network connector indicates that a network
connection has been established, and the yellow indicator blinks when network data is sent or
received