Functions Of Special Auxiliary Relays And Special Data Registers - Delta Electronics AH500 Manual

A H 5 00 M o ti on C on tr ol M od ul e Ma nua l
3.13 Functions of Special Auxiliary Relays and Special
Data Registers
1.
Op e ra tio n
fla gs
SM000~SM003
2.
3.
4.
1.
Wat ch d o g
time r
2.
SR000
3.
4.
3 - 2 8
SM000: If the module runs, SM000 will be a normally-open contact (Form
A contact). When the module runs, SM000 is ON.
SM000
If the module r uns , SM000 will
be a nor mally- open contac t.
SM001: If the module runs, SM001 will be a normally-closed contact
(Form B contact). When the module runs, SM001 is OFF.
SM002: A positive-going pulse is generated at the time when the module
runs. The width of the pulse is equal to the scan cycle. If users
want to initialize the module, they can use the contact.
SM003: A negative-going pulse is generated at the time when the module
runs. The width of the pulse is equal to the scan cycle.
T he modul e runs.
SM000
SM001
SM002
SM003
The watchdog timer is used to monitor a scan cycle. If the scan cycle is
greater than the watchdog timer value, the ERROR LED indicator on the
module will be turned ON, and all the output devices will be turned OFF.
The watchdog timer is initailly set to 200. If the program is long, or the
operation is complex, users can change the watchdog timer value by
means of the instruction MOV. In the example below, the watchdog timer
value is changed to 300.
SM002
0
Initial pulse
The maximum value which can be stored in the watchdog timer is 32,767.
However, the larger the watchdog timer value is, the more time it takes to
detect any operation error. As a result, if there is no complex operation
resulting in a scan cycle longer than 200 milliseconds, it is suggested that
the watchdog timer value should be less than 200.
If an opration is complex, the scan cycle may be long. Users can check
whether the scan cycle is greater than the value stored in SR000 by
monitoring SR010~SR012. If the scan cycle is greater than the value
stored in SR000, the users can change the value in SR000.
T he module is running.
Y0.0
Y0.0 is ON.
Scan cycl e
SR000
MOV K300