Emerson Process Management OXYMITTER 4000 - Manual (Page 135)

Instruction Manual
IB-106-340C Rev. 4.1
July 2004
Rosemount Analytical Inc. A Division of Emerson Process Management Maintenance and Service 9-17
Hazardous Area Oxymitter 4000
12. If previously removed, install the entire
electronics per paragraph 9-4b, steps
4 and 5.
13. Follow the instructions in paragraph
2-1b to install the Hazardous Area
Oxymitter 4000 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.
i. Ceramic Diffusion Element Replacement
NOTE
This procedure applies to the ceramic
diffuser element only.
1. General
The diffusion element protects the O
2
cell from particles in process gases.
The element does not normally 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.
Examine the ceramic diffusion element
whenever removing the probe for any
purpose. Replace if damaged.
Damage to the diffusion element may
become apparent during calibration.
Compare probe response with previous
response. A broken diffusion element
will cause a slower response to cali-
bration 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 11-1.
2. Replacement Procedure
(a) Follow the instructions given in
paragraph 9-4a to remove the
Hazardous Area Oxymitter 4000
from the stack or duct.
(b) Loosen setscrews, Figure 9-10,
using hex wrench from Probe
Disassembly Kit, Table 11-1 and
remove vee deflector. Inspect
setscrews. If damaged, replace
with stainless setscrews coated
with anti-seize compound.
(c) On systems equipped with abra-
sive shield, remove dual dust seal
gaskets.
(d) Use spanner wrenches from the
Probe Disassembly Kit, Table
11-1, to turn hub free from retainer.
(e) Put the hub in vise. Break out old
ceramic diffusion element with
chisel along cement line and 9.5
mm (3/8 in.) pin punch through
cement port.
(f) Break out remaining ceramic diffu-
sion element by tapping lightly
around hub with hammer. Clean
grooves with pointed tool if neces-
sary.
(g) Replace ceramic diffusion element
using the ceramic diffusion ele-
ment replacement kit in Table
11-1. This consists of a diffusion
element, cement, setscrews, anti-
seize compound and instructions.
(h) Test fit replacement ceramic diffu-
sion element to be sure seat is
clean.
Do not get cement on ceramic diffu-
sion element except where it touches
the hub. Any cement on ceramic diffu-
sion element blocks airflow through
element. Wiping wet cement off of the
ceramic only forces cement into
pores. Also do not get any cement
onto the flame arrestor element.
(i) Thoroughly mix cement and insert
tip of squeeze bottle into cement
port. Tilt bottle and squeeze while
simultaneously turning ceramic
9