Hydronix Interface Units; Digital Input/Output Connection; Figure 24: Internal/External Excitation Of Digital Input 1 & 2; Figure 25: Activation Of Digital Output 2 - Hydronix Hydro-Probe XT User Manual

Chapter 3

4 Hydronix Interface Units

For connection to any of the current range of Hydronix controllers and interface units please refer
to the documentation supplied with the relevant unit.

5 Digital input/output connection

The Hydro-Probe XT has two digital inputs, the second of which can also be used as an output
for a known state. Full descriptions of how the digital inputs/outputs can be configured are
included in Configuration from Page 35. The most common use of the digital input is for batch
averaging, where it is used to indicate the start and end of each batch. This is recommended as
it provides a representative reading of the full sample during each batch.
An input is activated using 15 – 30v DC into the digital input connection. The sensor power
supply may be used as an excitation supply for this, or alternatively an external source may be
used as shown below.
0975A twisted
pair Sensor
Cable
Internal Excitation – IP1
When the digital output is activated the sensor internally switches pin J to 0v. This can be used
to switch a relay for a signal such as 'bin empty' (see Chapter 3). Note that the maximum current
sink in this case is 500mA and in all cases over current protection should be used.
30 Hydro-Probe XT User Guide HD0538 Rev: 1.6.0
Figure 24: Internal/external excitation of digital input 1 & 2
0975A
twisted pair
Sensor
Cable
Digital Output Switch – example using 'Bin Empty'
signal to turn on a lamp

Figure 25: Activation of digital output 2

Electrical Installation and Communication
0975A twisted
pair Sensor
Cable
External Excitation – IP1
AC
15-30Vdc