Xylem SDI-12 Data Logger iRIS 220, iRIS 320, iRIS 350, iRIS 150, iRIS 300 - Manual (Page 59)

53 iQuest (NZ) Ltd - PO Box 15169, Hamilton, New Zealand Tel: +64 7 857-0810 Fax: +64 7 857-0811 Email: [email protected]
6.5 Connecting an Up/Down Water Level Instrument
A relatively common type of digital water level instrument is one that provides two pulse outputs. One output
generates a pulse for each increment and the other for each decrement in level. The iRIS maintains a record
of these steps and therefore the relative level.
This instrument type is NOT the same as a quadrature encoder which uses the relative phase
of the two signals to determine direction. See Section 6.9 for details on the quadrature
sensors.
These 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 connects for such an installation. The incrementing output must be
connected to DI1 and the decrementing output to DI2.
TOP iRIS I/O Connector
*
BOTTOM
A typical sensor configuration example for this type of installation is shown below. The instrument is a
standard digital up/down water level encoder. The level is averaged and the result logged every 15 minutes.
* Sensor 1 Cfg
(Now: 0.0)
0 Exit
1 Source [11: Up/Dn]
2 Name [Water Lvl]
3 Mode [Period Avg]
4 Multiplier [ 0.001]
5 Offset [ 0.000]
6 Log Multiplier [1000]
7 Log Rate [15min]
8 Alarms
9 Data
AI4
AI3
AI2
AI1
AGND
AOUT
DIO4
DIO3
DIO2
DIO1
SDI-12
DGND
12V+
GND (-)
VIN+
GND (-)
- +
External
12V Battery
(Optional)
DN
Up/Down
UP Water Level
+12V Sensor
0V
Charging source
e.g. solar panel