Sierra 241-VTP, 240-VTP instruction manual Column One Hidden Diagnostics Values

Chapter 4 Troubleshooting & Repair Series 24-HP Instruction Manual

Column One Hidden Diagnostics Values

•f = vortex shedding frequency (Hz).

•fi = adaptive filter – should be approximately 25% higher than the vortex shedding frequency, this is a low-pass filter. If the meter is using the Filter Control (see below) in the manual mode, fi will be displayed as fm.

•G = gain (applied to vortex signal amplitude). Gain defaults to 1.0 and can be changed using the Gain Control (see below).

•A = Amplitude of vortex signal in Volts rms.

•A1, A2, A3, A4 = A/D counts representing the vortex signal amplitude. Each stage (A1-A4) cannot exceed 512. Beginning with stage A1, the A/D counts increase as the flow increases. When stage A1 reaches 512, it will shift to stage A2. This will continue as the flow rate increases until all 4 stages read 512 at high flow rates. Higher flow rates (stronger signal strength) will result in more stages reading 512.

•Kc, It, Kb = profile equation (factory use only). Model M23 only

•V = calculated average pipe velocity (ft/sec).

•Re = calculated Reynolds number.

•RTD1 = resistance value of integral RTD in ohms.

•RTD2 = optional RTD resistance value same as above

•Pe(v) = pressure transducer excitation voltage

•Pv(v) = pressure transducer sense voltage.

•Stnd = density of fluid at standard conditions

•Nrml = density of fluid at normal conditions

•Viscosity = calculated viscosity of flowing fluid

•Ck = calculated Ck at current operating conditions. Ck is a variable in the equation that relates signal strength, density, and velocity for a given application. It is used for noise rejection purposes. Ck directly controls the fi value (see above). If the Ck is set too low (in the calibration menu), then the fi value will be too low and the vortex signal will be rejected resulting in zero flow rate being displayed. The calculated Ck valun in this menu can be compared to the actual Ck setting in the cali- bration menu to help determine if the Ck setting is correct.

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