Figure 27: Out With Lockval"Lock; Figure 28: Out With Lockval "No Lock - Honeywell SLG 700 Option Manual

A configuration error shall be set in BLOCK_ERR and the actual mode of the block shall go to Out of
Service if the X values have any of the following conditions:
X21 < X11, X12 <= X11, X22 <= X21.
The parameter LOCKVAL provides an option to specify whether OUT_1 remains at its ending level
when control is switched to OUT_2, or goes to Y11. If LOCKVAL is "LOCK", OUT_1 remains at its
ending value when X is greater than X12. If LOCKVAL is "NO LOCK", then OUT_1 goes to Y11
when X is greater than X12. Some hysteresis in the switching point may be required because the
output may change by a full stroke of the valve. HYSTVAL contains the amount of hysteresis. If X <=
X12-HYSTVAL, OUT_1 may be determined by the calculated y value. If X12-HYSTVAL < X < X12
and X has not reached X12 since it was less than X12-HYSTVAL, OUT_1 may be determined by the
calculated y value. If X transitioned from a value > X12 to a value where X12-HYSTVAL < X < X12,
then the value of OUT_1 is determined by the LOCKVAL setting. If X12 < X, OUT_1 may be
determined by the LOCKVAL setting.
In the following example LOCKVAL ="LOCK":

Figure 27: OUT with LOCKVAL"LOCK"

In this example LOCKVAL= "NOLOCK"

Figure 28: OUT with LOCKVAL "NO LOCK"

Rev.5 FOUNDATION Fieldbus Option User's Manual Page 111