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

iRIS Datalogger User Guide V1.50
6 iQuest (NZ) Ltd - PO Box 15169, Hamilton, New Zealand Tel: +64 7 857-0810 Fax: +64 7 857-0811 Email: [email protected]
2.3.10 Gateway Communication
The iRIS supports iQuest protocol gateway functionality between the wireless network and the RS232 serial
interface. This enables the unit to be used as a bridge between the wide area wireless network and a
localised radio or other network. It is possible to connect a datalogger that does not have wireless capability
such as the iQuest DS-4483 to the serial port of the iRIS and communicate with it via the gateway. Also, by
connecting a data radio to the unit’s serial port it is possible to communicate with several devices in a multi-
drop radio network from the wireless network.
When the gateway option is enabled, any data packets that are not addressed to the iRIS and match the
gateway criteria are readdressed and redirected. The port that the redirected packet is sent from depends
on the configuration of the iRIS.
Refer to Section 9 - RS232 Interface Telemetry for further information on using the gateway.
2.4 iRIS 220/320 and iRIS 350 Comparison
The iRIS 350 is the successor to the iRIS 320 (and its sub-model, the iRIS 220). The iRIS 350 hardware
design is largely based on the iRIS 320 but with several enhancements. The current releases of
firmware/software are virtually identical to the iRIS 220/320. The additional on-board resources will be
utilised in future software developments. The key hardware differences between the models are:
iRIS 220/320 iRIS 350
Analog Inputs - 12 bit resolution
- Raw reading 0 to 5000mV
- External sink resistors are required
for current inputs. These are normally
250 ohm giving 0 to 5000mV for 0 to
20mA input signal. - 16 bit resolution
- Raw reading 0 to 5.0000V
- Built in 100 ohm link selectable
sink resistors for current sources.
This produces input range 0 to
2.0000V for 0 to 20mA signal.
Analog Output
(Excitation) Fixed 5V Reference Variable 0-5V or 0-20mA active
output.
(Fixed in software 5V for initial
version)
Digital I/O 2 x Inputs
1 x Pull-down Output
1 x Switched 12V Output 4 x Digital I/O channels that can be
either inputs, or outputs
(Fixed in software to iRIS 320
configuration for initial version)
Real Time Clock
backup Miniature soldered-in lithium coin cell.
~15 months life of cumulative backup
while iRIS not powered up. User replaceable “Snap-Hat”
battery module. ~7 years life of
cumulative backup while iRIS not
powered up.
Onboard RAM 8KB 32KB
LCD 4 lines x 12 character test plus a set of
fixed icons. Full graphics LCD 64 x 128 pixels.
(Initial software emulates the
iRIS 320 LCD, but has 4 lines x
19 character text)
iRIS-CAM
Interface Plug-in option board. Built in.
Table 2 - Hardware Differences
Important! Analog Input Scaling. Any user familiar with the earlier iRIS 220/320 will be
immediately at home with the iRIS 350.
However, the analog inputs in the iRIS 350 deliver raw values as floating-point volts (0.0000 to
5.0000) rather than integer millivolts (0 to 5000). Therefore any scaling multiplier / offset values
chosen must take this difference into account.