Emerson B-106-300NH instruction manual Replacement of Contact Thermocouple Assembly

Instruction Manual

Appendix A Rev. 3.8 July 2002

World Class 3000

11.Wipe a heavy layer of anti-seize com- pound onto the threads and mating surfaces of the diffusion hub and retainer.

12.Assemble retainer and diffusion hub with two pin spanner wrenches. Torque to 10 ft-lbs (14 N·m).

13.On systems equipped with abrasive shield, install dust seal gaskets with joints 180° apart.

14.Reinstall vee deflector, orienting apex toward gas flow. Apply anti-seize com- pound to setscrews and tighten with hex wrench.

15.Reinstall probe on stack flange.

16.Turn power on to electronics and monitor thermocouple output. It should stabilize at 29.3 ±0.2 mV. Calibrate probe per Instruction Bulletin applica- ble to your electronics package.

A-13 REPLACEMENT OF CONTACT AND

THERMOCOUPLE ASSEMBLY

Use heat resistant gloves and cloth- ing when removing probe junction box and inner probe assembly. Do not at- tempt to work on these components until they have cooled to room tem- perature. Probe components can be as hot as 800°F (427°C). This can cause severe burns.

Disconnect and lock out power before working on any electrical components. There is voltage up to 115 Vac.

a.Disconnect and lock out power to electron- ics. Using heat resistant gloves and cloth- ing, remove probe junction box cover.

Squeezing tabs on hose clamps, remove hoses from probe junction box, Figure A-21.Remove four screws in corners of probe junction box. Pull probe junction box and in- ner probe assembly free from probe tube. Set on bench and allow to cool to room temperature.

b.Disconnect cell extension wire (orange), thermocouple wire (red alumel), and ther- mocouple wire (yellow chromel) by cutting bomb tail connections from the terminal strip, Figure A-18.

c.Remove two screws, Figure A-21,lock- washers, and flat washers that connect probe junction box to inner probe assembly. Pull heater, V-strut and backplate assembly away from probe junction box. Inspect all O-rings and insulating gasket; replace if worn or damaged.

PROBE JUNCTION BOX TO HEATER,

STRUT, AND BACKPLATE

ASSEMBLY SCREW

PROBE JUNCTION BOX

INNER PROBE ASSEMBLY

TO PROBE TUBE SCREWS

PROBE

JUNCTION

BOX

HOSE

CLAMP

HOSE

21240027

Figure A-21. Probe Junction Box Mechanical

Connections

A-20 Appendices Rosemount Analytical Inc. A Division of Emerson Process Management