WI-I/O 9-K
v1.9
Page 32
⊂
⊂
GND
AI-
WI-I/O K
⊂
⊂
+
-
AI+
WI-I/O K
⊂
LOOP POWERED TRANSDUCER
EXTERNALLY POWERED TRANSDUCER
⊂
⊂
⊂
+
-
AI+
AI-
ANALOG
SUPPLY
⊂
⊂
GND
Each input has a loop resistance of 150
Ω
and zener
diode protection against overvoltage and reverse
voltage.
Voltage Input
Voltage inputs are connected to the AI+ and AI-
connections. The maximum voltage signal that can be
measured is 10V.
The analog signal is set up for a 4-20mA signal in the
factory. To use a voltage input, change the jumpers (old
version) or slide switch (new version) inside the module:
1.
Remove the lid from the unit.
2.
With the unit oriented with the antenna connector at
the top of the unit, locate the selector jumpers or
switch at the bottom right corner of the box.
3.
New Version – Switch. When the switch is slid to the
right side (default), the analog input is set for a mA
signal; when slid to the left, it is set for a voltage
signal.
Old Version - Jumpers. Using long-nose pliers,
remove the two jumpers bridging the left-hand and
middle pins, and insert the jumpers between the
middle and right-hand pins. When the jumpers are on
the left side (default), the analog input is set for a mA signal; when on the right side, it is set
for a voltage signal. If used in a Class1 Division 2 Hazardous Location, the PCB jumpers
must be secured in place with glue or silicon.
Shielded cable is recommended for both mA and voltage analog input loops to minimise induced
noise and radio frequency interference (RFI). The shield of the cable must be connected to earth
at one end of the cable only. Additional surge protection is recommended in high electrical noise
environments, or if the analog signal cable runs for a long distance underground before
⊂
+
-
AI+
WI-I/O K
⊂
VOLTAGE INPUT
AI-
⊂
⊂
GND
mA
V
mA
V
Old Version - Links
New Version -
Switch
