CiDRA SONARtrac HD VF-100 User Manual

Page 79

Page 10-4

20638-02 Rev 01

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

below or above the maximum flow rate setting. Default is ‘Enable’,
where the 4-20mA output will go to min or full scale. If this option is
‘Disabled’, the meter will output as previously set up in ‘Out of
Range

’ when the meter goes below or above the flow rate range.

‘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 62

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:

- 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).