GE PanaFlow HT, Руководство пользователя

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Chapter 3. Initial Setup and Programming
40 PanaFlow HT User’s Manual
3.6 User Preferences
CAUTION! Changing program parameters could result in an inaccuracy in the flow measurement, which
could violate the functional safety of the product. Always use caution when changing
parameters at the SIL User Level. These parameters, which are functional safety related, shall
be entered and validated by a suitably skilled and qualified person (Authorized User).
Note:
Any changes made at SIL User Level must be followed by a validation step. There are two components to the
validation process.
1. Review parameter changes before committing them to the flowmeter. This process happens automatically by the
programming interface (display/keypad, Vitality software, or HART). Be sure program parameters are correct
before issuing the Commit command.
2. After returning to Measure mode, review the measurement parameters in Table 2 below to verify they are in an
acceptable range. This completes the validation process.
Table 2: Criteria for SIL Requirements
Measurement Expected Actual Criteria Verdict (P/F)
Ch1 Sound Speed < 0.5% difference
Ch1 Velocity < 0.5% difference
Ch1 Up Amp Discriminator > 14 and < 32
Ch1 Dn Amp Discriminator > 14 and < 32
Ch1 SNR Up > 10 > 5
Ch1 SNR Dn > 10 > 5
Ch1 Active TWup Within ±15% of the static TW value.
Ch1 Active TWdn Within ±15% of the static TW value.
Ch1 Error Status 0x00000000 0x00000000
Ch1 Error # 0 < 8
Ch2 Sound Speed < 0.5% difference
Ch2 Velocity < 0.5% difference
Ch2 Up Amp Discriminator > 14 and < 32
Ch2 Dn Amp Discriminator > 14 and < 32
Ch2 SNR Up > 10 > 5
Ch2 SNR Dn > 10 > 5
Ch2 Active TWup Within ±15% of the static TW value.
Ch2 Active TWdn Within ±15% of the static TW value.
Ch2 Error Status 0x00000000 0x00000000
Ch2 Error # 0 < 8
Composite Velocity < 0.5% difference
Composite Volumetric < 0.5% difference
SIL Output mA 4 mA <= x <= 20 mA