Hazardous Area Oxymitter DR

Instruction Manual

IB-106-340CDR Original Issue January, 2002

g.If the contact assembly is damaged, replace the strut or the contact pad. Instructions for replacing the contact pad are in the cell re- placement kit.

h.Remove and discard the corrugated seal. Clean the mating faces of the probe tube and retainer. Remove burrs and raised surfaces with a block of wood and crocus cloth. Clean the threads on the retainer and hub.

i.Rub a small amount of anti-seize compound on both sides of the new corrugated seal.

j.Assemble the cell and flange assembly, cor- rugated seal, and probe tube. Make sure the calibration tube lines up with the cali- bration gas passage in each component. Apply a small amount of anti-seize com- pound to the screw threads and use the screws to secure assembly. Torque to

4 N·m (35 in-lbs).

k.Install the termination housing per the instructions in paragraph 4-5steps c through e.

l.Apply anti-seize compound to the threads of the cell assembly, hub, and setscrews. Re- install the hub on the cell assembly. Using pin spanner wrenches, torque to 14 N·m

(10 ft-lbs). If applicable, reinstall the vee de- flector, orienting apex toward gas flow. Se- cure with the setscrews and anti-seize compound. Torque to 2.8 N·m (25 in-lbs).

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

n.Reinstall the probe and gasket on the stack flange.

o.Follow the instructions in paragraph 4-3bto install the Hazardous Area Oxymitter DR into the stack or duct. If there is an abrasive shield in the stack, make sure the dust seal gaskets are in place as they enter the 15° reducing cone.

p.Turn on power and monitor thermocouple output. It should stabilize at 29.3+0.2 mV.

Set reference air flow at 56.6 l/hr (2 scfh). After the Hazardous Area Oxymitter DR sta- bilizes, calibrate the unit. If new components have been installed, repeat calibration after 24 hours of operation.

4-8 CERAMIC DIFFUSION ELEMENT REPLACEMENT

NOTE

This refers to the ceramic diffusion element only.

a.

General

 

 

The diffusion element protects the cell from

4

 

particles in process gases. Normally, it does

 

 

not need to be replaced because the vee

 

 

deflector protects it from particulate erosion.

 

 

 

 

In severe environments, the filter may be

 

 

broken or subject to excessive erosion. Ex-

 

 

amine the ceramic diffusion element when-

 

 

ever removing the probe for any purpose.

 

 

Replace if damaged.

 

 

Damage to the ceramic diffusion element

 

 

may become apparent during calibration.

 

 

Compare probe response with previous re-

 

 

sponse. A broken diffusion element will

 

 

cause a slower response to calibration gas.

 

 

Hex wrenches needed to remove setscrews

 

 

and socket head screws in the following

 

 

procedure are available as part of a Probe

 

 

Disassembly Kit, Table 7-1.

 

b.

Replacement Procedure

 

 

1. Follow the instructions in paragraph

 

 

4-3ato remove the Hazardous Area

 

 

Oxymitter DR from the stack or duct.

 

2. Loosen setscrews, Figure 4-5,using hex wrench from Probe Disassembly Kit, Table 7-1,and remove vee deflec- tor. Inspect setscrews. If damaged, re- place with stainless setscrews coated with anti-seize compound.

Rosemount Analytical Inc. A Division of Emerson Process Management

Maintenance and Service 4-7

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Emerson oxymitterdr hazardous area in-siu oxygen probe Ceramic Diffusion Element Replacement, Replacement Procedure