Mitsubishi Electric R60AD8-G - Page 52

50
1 FUNCTIONS
1.7 Input Signal Error Detection Function
Setting example
■Setting example of the input signal error detection
In the channel where the following values are set, an input error is detected when an analog input value exceeds 21.6mA or
falls below 0.8mA.
Assign the following values in a formula to determine the input signal error detection setting value from the input signal error
detection upper limit value and input signal error detection lower limit value.
• Input signal error detection upper limit value: 21.6mA
• Input signal error detection lower limit value: 0.8mA
• Offset value: 4.0mA
• Gain value: 20.0mA
For details on the calculation formula, refer to the following.
Page 43 Setting the input signal error detection upper or lower limit value
Thus, set 'CH1 Input signal error detection setting value/CH1 Input signal error detection lower limit set value' (Un\G142) to
the determined input signal error detection setting value (200 (20.0%)).
Thus, set 'CH1 Input signal error detection upper limit setting' (Un\G150) to the determined input signal error detection setting
value (100 (10.0%)).
The following figure shows the operation with the determined input signal error detection setting values.
Item Setting value
Mode Q compatible mode
Input range 4 to 20mA
Input signal error detection auto-clear enable/disable setting (Un\G162) Disable (1)
Input signal error detection extension/input signal error detection setting (Un\G47) Upper limit value/lower limit value different (1)
[Calculation of lower limit value]
=
= 200 (20.0%)
Input signal error detection setting value × 1000
4.0 - 0.8
20.0 - 4.0
[Calculation of upper limit value]
=
= 100 (10.0%)
Input signal error detection setting value × 1000
21.6 - 20.0
20.0 - 4.0
21.6mA
20mA
4mA
1.6mA
3.2mA
16mA
0.8mA
Input signal error detection
upper limit value
Gain value
Lower limit value of input
range (offset value)
Input signal error detection
lower limit value
Error
detected
Error
detected
(10.0% of 16mA)
(20.0% of 16mA)
(Gain value - Offset value)