Chapter 13 Analog Input Module (XBF-AD04C)
13.6.4 Detecting disconnection wire
In case that Input voltage(DC 1~5V) or Input current (DC 4~20 mA) is chosen with analog input range,
the analog input module has diagnostic function by checking disconnection and showing.
If the module shows disconnection, that means the parts of connections in the wiring connection are
faulty. If so, check and take action.
(1) Detection conditions
When input signal range of 4~20mA and 1~5V is used, disconnection of input circuit can be
detected. The detection conditions of each input signal range are as below.
Input signal range Voltage/Current recognized as a disconnection
4 ~ 20 ㎃ 0.8 ㎃ or less
1 ~ 5 V 0.2 V or less
(2) When between used wiring and module is disconnected, the LED will be turned on/off 1s intervals
and make an error code.
(3) Each channel can detect disconnection. However, Disconnection is only displayed for specified
operation channel. The LED can commonly use the channel from 0 to 3. If one or more channel is
disconnected, LED will be turned on/off.
Input connections
LED condition
Normal
Operation On Off
Stop On Off
Input wiring is disconnected
or Input is not connected.
Operation
On
Stop On Off
(4) In case of disconnection, disconnection flag of relevant channel will turn on and In case of
connection, disconnection flag of relevant channel will turn off.
Disconnection flag
Description Condition
XBM/XBC XEC
U0y.10.0 %UX0.y.160 Channel 0 disconnection
Off: Normal
On: Disconnection
U0y.10.1 %UX0.y.161 Channel 1 disconnection
U0y.10.2 %UX0.y.162 Channel 2 disconnection
U0y.10.3 %UX0.y.163 Channel 3 disconnection
※ The 'y' is a slot number equipped with a module.
(5) In case of disconnection, the input value displays the lowest value among each input range.
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