ABB RELION REF615R, Technical Manual

Page: 96 / 664

Shift selector
When the function is first enabled,
O1
is set to TRUE.
Each rising edge of the
SHIFT
input turns the presently asserted output
Ox
(x = 1...8) to
FALSE and turns the next higher enabled output to TRUE. Figure 36 shows a logic
diagram with all outputs enabled. If there is no higher enabled output,
O1
is set to TRUE.
Figure 37 shows a logic diagram with outputs O2, O7, and O8 disabled.
Only one output can be set to TRUE at a time. An internal variable, ASSRTD_OUT, is
updated to store the number of the asserted output. The range of ASSRTD_OUT is 1...8
and is available through the Monitored data view. Each time a rising edge on the SHIFT
input causes the output to change, an event is generated that includes the number of the
new asserted output.
The value ASSRTD_OUT is stored in a non-volatile memory. The value is used to set the
corresponding output to TRUE at initialization. If the
Operation setting is set from “Off”
to “On”, the value of ASSRTD_OUT is initialized to 1 and
O1
is set TRUE.
The outputs
O2
...
O8
can be disabled by setting the corresponding Ox enable (x = 2 to 8)
setting from “Enable” to “Disable”. Output
O1
has no corresponding setting and is always
enabled.
SHIFT
HOLD
RESET
O6
O7
O8
O5
O4
O3
O2
O1
GUID-83C51F78-42FF-4F05-A115-B08062D4D9C6 V1 EN
Figure 36: Logic diagram with all outputs enabled
Section 3
1MRS240050-IB C
Basic functions
90 REF615R
Technical Manual