CiDRA SONARtrac GVF-100 - Manual (Page 82)

Copyright © 2006 CiDRA Corporation Page 10-6
20675-01 Rev 02
Connect reference meter to
the 4-20 Loop and enter the
meter value below.
NOTE: You must first perform 4mA Trim first
Press ENTER to Continue
‘4mA and 20mA Trim’ – allows user to adjust the transmitter 4-20mA
outputs to match the plant standard or loop control. The following
message screen will appear when this menu item is selected.
Figure 61 4-20mA Trim Message box
Press ‘ENTER’ to clear the warning and ‘ENTER’ to input the current
value measured on the reference meter. Press ‘ENTER’ to complete
the input and repeat for the 20mA menu selection. These
measurements will calculate and apply an offset and slope (can be
viewed on the ‘INFO>CONFIGURATION>4-20mA Channel 1 (or 2)’
screen) for the selected channel.
•
Pulse
The SONARtrac Pulse Output utilizes a solid-state relay closure to
output a pulse train. The solid-state relay is rated for +30VDC to
–10VDC, 100mA maximum. An external user supplied power source
(pull-up) is connected to the (+) and (-) terminals under the word
“Pulse” on the terminal board. The Pulse Output can be configured to
output a pulse frequency or a number of pulses for one of the
following measurements:
- Speed of Sound (SOS) : Outputs a frequency corresponding to
SOS.
- Gas Volume Fraction (GVF) : Outputs a frequency corresponding
to GVF.
- Flow Rate (VF) : Outputs a frequency corresponding to flow rate.
- Flow Rate % : Outputs a frequency corresponding to % of VF full-
scale range.
- Total Flow (Totalizer) : Outputs a series of pulses corresponding
to the total number of flow units counted over the previous update
interval.
Menu options for configuring the output include a multiplier, a pulse
width, and a low cut setting (see descriptions below).
‘Multiplier’ - A factor used to scale the pulse output where:
scaled pulse quantity = (pulse output parameter) / multiplier value
‘Pulse Width’ - Sets the width of the Pulse output in seconds (0.5ms,
1ms, 20ms, 33ms, 50ms, 100ms).