Omega FMA 5400A - Full Scale Flow Adjustment; 25% Flow Adjustment; 75% Flow Adjus7.3.16 100% Flow Adjustment; LCD Display Scaling

28
7.3.12 Full Scale Flow Adjustment
Fully open the flow regulator upstream of the FMA 5400A/5500A. Increase the inlet
pressure to 20 psig. Apply a +5.00 Vdc (100% full scale flow) setpoint reference.
Using the calibrator check the flow rate. If necessary, adjust R33 to match the
desired full scale flow rate. [In control mode, turning R33 clockwise will decrease
the flow. Conversely, turning R33 counterclockwise will increase the flow through
the FMA 5400A/5500A.]
7.3.13 25% Flow Adjustment
Change the setpoint to 1.25 Vdc to control at 25% of full scale flow. Check the
flow rate indicated against the flow calibrator. If the flow is not within ±0.75%
of full scale, re-adjust the setting for potentiometer [R33], until the flow output is correct.
7.3.14 50% Flow Adjustment
Change the setpoint to 2.50 Vdc to control at 50% of full scale flow. Check the
flow rate indicated against the flow calibrator. If the flow is not within ±0.75%
of full scale, re-adjust the setting for potentiometer [R38], until the flow output is correct.
7.3.15 75% Flow Adjustment
Change the setpoint to 3.75 Vdc to control at 75% of full scale flow. Check the
flow rate indicated against the flow calibrator. If the flow is not within ±0.75%
of full scale, re-adjust the setting for potentiometer [R39], until the flow output is correct.
7.3.16 100% Flow Adjustment
Change the setpoint to 5.00 Vdc to control at 100% of full scale flow. Check the
flow rate indicated against the flow calibrator. If the flow rate is not within ±0.75%
of full scale, re-adjust the setting for potentiometer [R40], until the flow output is correct.
Repeat steps 7.3.13 to 7.3.16 at least once more.
7.4 LCD Display Scaling
It may be desirable to re-scale the output reading on the LCD readout supplied
with certain model FMA 5400A/5500A transducers. Re-calibration for a new flow
range or different engineering units are two examples of when this may be nec-
essary.
7.4.1 Access LCD Display Circuit
Carefully remove the LCD from the FMA 5400A/5500A or panel mounted surface.
Remove the aluminum housing on the side of the connection cable. Slide the LCD
assembly out of the aluminum housing.