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GE Oil & Gas
Table 9: Operational Specifications
Accuracy
+/- 0.5% (t/-0. 10% or less) Full Span
Hysteresis and Deadband
+/- 0.3% Full Span
Repeatability
+/- 0.3% Full Span
Conformity
+/- 0.5% Full Span
Start-Up Drift
Less than 0.02% in first hour
Long Term Drift
Less than 0.003% per month
Position Travel Limits
Rotary: 18 - 140°
Reciprocating: 0.25” - 2.5“ (6 mm - 64 mm)
Note:
Above 2.5” (64 mm) consult factory for mounting
instructions.
Flow Characteristics
Applied in addition to the control valve’s inherent charac-
teristic.
Linear
Equal Percentage (of 50:1 or 30:1)
Camflex
Quick Opening (inverse of 50:1 equal percentage)
User Configurable
Tight Shut Off (0 -20% of input)
Position Auto Tune
SVI II AP performs automatic determination of the opti-
mal valve position control parameters. In addition to P, I,
D, the position algorithm uses damping, symmetry for
exhaust and fill time constants, dead zone and magni-
tude characterization parameters. Auto Tune is opti-
mized for 5% step changes with negligible overshoot.
After the Auto Tune process is completed, the user can
further adjust the positioner tuning parameters to more
conservative or to more responsive values.
Proportional gain: 0 to 5, displayed as 0 to 5000
Integral time: 0 to 100 seconds - displayed as 0 to 1000 (1/
10s)
Derivative time: 0 to 200 milliseconds
Dead Zone: 0 to +/-5% (0 to 10% deadband)
Padj: +/- 3000 (depends on P)
Beta (non-linear gain factor): -9 to +9
Stroking Time: 0 to 250 seconds
Position compensation coefficient: 1 to 20
Boost: 0 to 20
Full open position adjustment
60 to 100% of actual stop
Start Up Time (from no power)
Less than 200 ms
Minimum current to maintain HART
®
3.0 mA
HART
®
Command #3 Mapping
HART
®
4-20 mA input signal
PV = Valve Position, 0-100%
SV = Actuator Pressure (P1-P2) (N/A for standard diagnostic
version; units sends zero)
TV = Supply Pressure
QV = P2 for double acting units (N/A for standard diagnos-
tic version; units sends zero)
HART
®
6 Commands
Cmd 9 - Reads device vars w/status.
Cmd 33 - Reads device variables.