Baker Hughes Masoneilan SVIII AP, Руководство по установке и обслуживанию

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Masoneilan SVI II AP Installation and Maintenance Manual =
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Internal Diagnostics
The SVI II AP performs internal self-diagnostics and hardware checks. When ValVue or HART
®
Handheld or the local display indicates that there are error messages write them down for
troubleshooting.
FAILSAFE Mode
Several of the internal diagnostics tests puts the SVI II AP into FAILSAFE mode if the errors
continue for a preset time. When the SVI II AP goes into FAILSAFE, the valve is driven to its
Failsafe position. It remains in that position until a technician clears the cause of the error and
resets the instrument. Reset is performed in two ways:
Connect a HART
®
modem and ValVue, and then click the RESET button.
or
Turn the power off and on.
To prevent the valve from moving after reset, put the controller in manual, and set the valve
position setpoint to the failsafe position 0% if ATO, 100% if ATC. You can set a special case of
FAILSAFE. You can set a Position Error Band and a Position Error Time 2 that forces the valve
to its failsafe position if the position error exceeds the band for a time longer than time 2. This
can be used on critical loops to force the process to trip if the positioner is unable to control
the valve.