User`s manual

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MELSEC-Q

3 SPECIFICATIONS

3.2.6 Disconnection detection function

(1) When the analog output value falls to or below 1ma accuracy (1.0%) in the

output range of 4 to 20mA or user range setting 1, the disconnection detection flag

(buffer memory address 49: Un\G49) and disconnection detection signal (XD) turn

ON and disconnection is detected.

Disconnection is detected only on the channel set for D/A conversion enable and

D/A output enable.

(2) The disconnection detection flag (buffer memory address 49: Un\G49) and

disconnection detection signal (XD) turn OFF when the operating condition setting

request (Y9) or disconnection detection clear request (YD) turns ON.

(3) For the disconnection detection function, the disconnection detection/warning

output setting (buffer memory address 47: Un\G47) allows enable/disable of the

disconnection detection to be specified for each channel. To enable the

disconnection detection, write "0" to the bit position corresponding to the channel

number and turn ON the operating condition setting request (Y9). The default is

all-channel disable.

Output monitor value (mA)

Disconnection detection

signal (XD)

OFF ON

Disconnection detection

clear request (YD)

OFF

Disconnection detection flag

(buffer memory address 49

: Un\G49)

OFF ON

OFF

Disconnection assumed range

POINT

If the analog output value is 1mA or less at the user range setting 1, disconnection

is detected if disconnection has not occurred actually.

When the analog output value is 1mA or less, disable the disconnection detection

function.