Emerson 4000 manual Check Valve Replacement, Pressure Regulator Optional Maintenance

Oxymitter 4000

Instruction Manual

IB-106-340 Rev. 3.0 December 2003

When installing the pressure switch, do not overtighten. Damage to the solenoid may occur.

9.Install new pressure switch (12). Be careful not to overtighten. Connect the leads to the proper terminals on the pressure switch.

10.Carefully install the board and spacer assembly into manifold (5) by aligning spacers (9) with the mounting holes on the manifold and securing with screws (11). Ensure o-rings (8) are installed between the spacers and the manifold surface.

11.Install manifold cover (14), and secure with manifold cover lock (6) and screw

(7).

12.Turn on the calibration gases at the cylinders.

e.Check Valve Replacement

Check valve (19, Figure 9-15)may stick or become plugged over time. Replace when necessary. If condensation deposits are noted upon removal, consider insulating the check valve.

f.Pressure Regulator (Optional) Maintenance

1.Pressure Adjustments. Reference air pressure regulator (8, Figure 9-15)is factory set to 20 psi (138 kPa). Adjust using the knob on top of the pressure regulator if necessary.

Do not use fingers to release valve stem. The valve may release air at high pressures and cause injury.

2.Condensation Drain. To drain excess moisture from the filter bowl of refer- ence air pressure regulator (8), use a screwdriver or comparable tool to peri- odically release valve stem on the bot- tom of the regulator.

g.Flowmeter Adjustments

1.Calibration Gas Flowmeter. Calibration gas flowmeter (17, Figure 9-15)regu- lates the calibration gas flow and must be set to 5 scfh. However, only adjust the flowmeter to 5 scfh after placing a new diffusion element on the end of the Oxymitter 4000. Adjusting the flowme- ter at any other time can pressurize the cell and bias the calibration.

In applications with a heavy dust load- ing, the O2 probe diffusion element may become plugged over time, caus- ing a slower speed of response. The best way to detect a plugged diffusion element is to note the time it takes the Oxymitter 4000 to return to the normal process reading after the last calibra- tion gas is removed and the calibration gas line is blocked off. A plugged ele- ment also can be indicated by a slightly lower reading on the flowmeter.

Change the diffusion element when the calibration gas flowmeter reads slightly lower during calibration or when the re- sponse time to the process flue gases becomes very slow. Each time the diffu- sion element is changed, reset the cali- bration gas flowmeter to 5 scfh and calibrate the Oxymitter 4000. For more information on changing the diffusion element, refer to paragraph 12.

2.Reference Air Flowmeter (Optional). Reference air flowmeter (16, Figure

9-15)regulates the reference air and must be set to 2 scfh. Adjust the flow with the knob on the bottom of the ref- erence air flowmeter when necessary.

Rosemount Analytical Inc. A Division of Emerson Process Management Maintenance and Service 9-23