SDM-SIO1 Serial Input/Output Module
4
2.2.2 SDM-SIO1 voltage specifications
Connection
Minimum
voltage
(1)
Nominal
voltage
(1)
Maximum
voltage
(1)
Power supply, +12V
connection
(2)
7V
12V
20V
RS-232 input threshold
Low
0.8V
-
-
RS-232 input threshold
High
-
-
2.4V
RS-232 input absolute
maximum
(2)
-
+/-15V
+/-18V
RS-232 input resistance
3 KΩ
5 KΩ
7 KΩ
RS-232 output voltage
swing
(3)
+/-5V
+/-5.4V
-
RS-232 output absolute
maximum
-
-
+/-13.2V
RS-485 input
(Differential)
200mV
(4)
-
6V
RS-485 output
(Differential)
2V (at 50
Ohms)
-
-
SDM lines (high level)
4.3V
5V
5.7V
SDM lines (low level)
0V
-
0.7V
(1) Values are volts D.C. (except resistances)
(2) It is NOT recommended that the user runs their SDM-SIO1 at maximum ratings for
extended periods of time
(3) Assuming a worst case 3 KΩ load
(4) It is not recommended that the user allows such low input voltages as there will be an
increased chance that external noise may cause errors in the incoming data
2.2.3 EMC compliance
The SDM-SIO1 has been tested and shown to comply with IEC 61326. The
device incorporates transient and surge protection that is designed to meet
IEC61000-4-5, level 4, providing the device is adequately grounded.
2.3 Temperature and humidity ranges
Temperature range
Minimum
Maximum
Notes
Standard range
-25ºC
+50ºC
Extended range
(optional)
-40ºC
+80ºC
(Contact Campbell
Scientific Ltd for further
extended temperature
requirements)
Humidity
Minimum
Maximum
Notes
Standard range
0%
95%
(non-condensing)