Azbil SVX100, Руководство пользователя

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20
The following valve actuator characteristics are automatically detected during autosetup:
„
Zero and span adjustment
(However, as a default, the span point is taken to be 0% of the overstroke. If a span adjustment
is performed after auto-setup completes, change the overstroke value and save the changed
value.)
„
Actuator operation setup
„
Lower Range Value (LRV) and Upper Range Value (URV) of input signal
If actuator operation is reverse operation: LRV = 4 mA, URV = 20 mA
If actuator operation is direct operation: LRV = 20 mA, URV = 4 mA
„
Actuator size setting
„
Hysteresis setting
WARNING
While auto-setup is running, the valve cycles from open to closed. Take appropriate
measures to prevent injury to personnel and adverse effects on the process.
SVX setting
If the valve action parameters set up for the SVX in Table 3-1 is the reverse values, Refer to
“4-4-3: Valve system” on page 36, in this document and set the valve action to the reverse
settings.
If the valve action parameters set up for the SVX in Table 3-1 is the direct values, no further
parameter settings are required. (The SVX is shipped from the factory set to direct mode.)
It is recommended that auto-setup and initial calibration of your SVX be performed using the
zero and span adjustment switches on the SVX.
You can also use a portable communicator to initiate auto-setup and initial calibration.
Because auto-setup and zero and span calibration must be observed for accurate valve
positioning, these two steps will typically be performed by zero and span adjustment switch.
Other functions including loop test, valve travel inquiry and tag number assignment require
an a communicator.
Table 3-1. SVX setting
Lever
Valve
Direction
Input signal
SVX Setting
Actuator
Action
Valve
Action
20
20
Up
Down
Up Down
Shut

Open
Direct
Close: 20 mA,
Open: 4 mA
Reverse Reverse
Reverse
Close: 4 mA,
Open: 20 mA
Direct Reverse
Open

Shut
Direct
Close: 20 mA,
Open: 4 mA
Direct Direct
Reverse
Close: 4 mA,
Open: 20 mA
Reverse Direct