Panametrics Sentinel User Manual page 60

Chapter 2. Initial Setup
2.6.1.4 Diagnostics
The diagnostics tab allows the user to display the following real time data, and to record some of the data as well
(refer to Figure 40 on page lxi):
• Flow Velocity: This is the un-averaged, instantaneous velocity.
• Sound Speed: This is the un-averaged, instantaneous speed of sound.
• Signal Max: This is the un-averaged instantaneous percent signal relative to the ADC reference.
• Delta T: This is the un-averaged instantaneous delta between up and down transmit time
• Delta T Offset: The Delta T Offset is an entry which belongs in the general tab. It is used to compensate for
system zero flow offset.
• Error: This display indicates the error number in the event that the meter has a error.
• Mode: There are three different regions at which the meter determines the topology for calculating the
transmit time. Each region is assigned a mode:
Mode 0: Phase mode
Mode 1: 2T to Fine/Course switch point = Chai
Mode 2: Bipolar Envelope
Mode 3: Unipolar Envelope
• % Error: The percent error indicates that the measurement system is rejecting reading due to error. It will
display the percent error which is proportion to the rejected data.
Up Stream/Down Stream:
• Signal: This is the signal strength in dB. The strength is inversely proportion to the receiver AGC gain level. The
signal strength is between 0 and 100.
• AGC: The AGC number is the DAC digital input value which controls the receiver gain control.
• Time: The transmit time is the total as seen from the DSP. It is the sum of: the time between the surface of the
two transducers, and Tw.
• P#: The P number is a point between 0 and 1024 on the receive window which is a function of the FIFO size.
60 Sentinel™ User's Manual