iRIS 350FX Reference Manual V1.50
64
HyQuest Solutions (NZ) Ltd
- PO Box 9466, Hamilton, New Zealand Tel: +64 7 857-0810 Email: [email protected]
Connecting a Unidata High-Speed Serial Instrument
Unidata high-speed serial instruments are supported by the iRIS, but with some conditions.
1.
Only 16 bit (two-byte) instruments can be used. Most water level encoders are of this type.
2.
A small hardware adaptor is required to interface the iRIS I/O to the instrument. This adaptor
comprises three 4K7 resistors as shown in the diagram.
The Unidata instruments normally require a 12V supply and this is readily obtained from the iRIS. A
supplementary 12V battery can be connected if desired. Typically, this type of instrument requires very little
current, so the internal iRIS battery will normally suffice. The diagram below shows the required connections
for such an installation. The connections must be done as listed.
Instrument
iRIS
SYNC
DIO3 with a 4K7 pull-up resistor to AOUT terminal set to a 5V output level.
CLOCK
DIO4 with two 4K7 resistors to adjust the voltage levels
DATA
DIO2 configured as an input.
TOP
iRIS I/O Connector
BOTTOM
A typical sensor configuration example for this type of installation is shown below. The instrument is a
Unidata 6809 serial water level encoder. The level in metres is averaged and the result logged every 15
minutes. The digital outputs are used to enable and clock the sensor. Outputs 3 and 4 should be enabled,
but set to an empty schedule with the polarity set as shown as the firmware controls the channels internally.
The digital output configuration is shown below.
AI4
AI3
AI2
AI1
AGND
AOUT
DIO4
DIO3
DIO2
DIO1
SDI-12
DGND
12V+
GND (-)
VIN+
GND (-)
- +
External
12V Battery
(Optional)
DATA
CLK
Unidata Serial
SYNC
Instrument
+12V
0V
Charging source
e.g. solar panel
All
Resistors
4K7
5%
Name: Water Lvl
Source: 16. HS SerI
Process Mode: Period Average
Multiplier: 0.001
Offset: 0.000
Log Rate: 15 mins
Output Mode: Schedule
Polarity: Pull-Down
Duration: 0 seconds
On Interval: 0 minutes
Off Interval: 0 minutes
Start Time: 00:00
End Time: 00:00
Output Mode: Schedule
Polarity: Inverted Pull-Up
Duration: 0 seconds
On Interval: 0 minutes
Off Interval: 0 minutes
Start Time: 00:00
End Time: 00:00
Summary of Contents for iRIS 350FX
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