Disassembly And Reassembly; Replacing The Integral Indicator - YOKOGAWA DPharp EJXC80A User Manual

6.4 Disassembly and
Reassembly
This section describes procedures for disassembly
and reassembly for maintenance and component
replacement.
Always turn OFF power and shut off and release
pressures before disassembly. Use proper tools for
all operations. Table 6.2 shows the tools required.
Table 6.2 Tools for Disassembly and Reassembly
Tool Quantity
Phillips 1
screwdriver
Slotted 1
screwdriver
Allen wrenches 3
Wrench 1
Torque wrench 1
Adjustable 1
wrench
Socket wrench 1
Socket driver 1
Tweezers 1
CAUTION
Precautions for ATEX Flameproof Type
Transmitters
• Flameproof type transmitters must be, as
a rule, removed to a non-hazardous area
for maintenance and be disassembled and
reassembled to the original state.
• On the flameproof type transmitters the two
covers are locked, each by an Allen head bolt
(shrouding bolt). When a shrouding bolt is
driven clockwise by an Allen wrench, it is going
in and cover lock is released, and then the
cover can be opened.
When a cover is closed it should be locked
by a shrouding bolt without fail. Tighten the
shrouding bolt to a torque of 0.7 N·m
Shrouding Bolt
Figure 6.2 Shrouding Bolts
Remarks
JIS B4633, No. 2
JIS B4648
One each, nominal 3, 4 and
2.5 mm Allen wrenches
Width across flats, 17 mm
Width across flats, 16 mm
Width across flats, 5.5 mm
.
{7 kgf·cm}
Shrouding Bolt
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<6. Maintenance>

6.4.1 Replacing the Integral Indicator

CAUTION
Cautions for Flameproof Type Transmitters
Users are prohibited by law from modifying the
construction of a flameproof type transmitter.
This would invalidate the agency approval for the
use of the transmitter in a rated area.
It follows that the user is prohibited from using
a flameproof type transmitter with its integral
indicator removed, or from adding an integral
indicator to a transmitter. If such modification is
absolutely required, contact Yokogawa.
This subsection describes the procedure for
replacing an integral indicator. (See figure 6.3)
■ Removing the Integral Indicator
1) Remove the cover.
2) While supporting the integral indicator with one
hand, loosen its two mounting screws.
3) Dismount the LCD board assembly from the
CPU assembly.
When doing this, carefully pull the LCD board
assembly straight forward so as not to damage
the connector pins between it and the CPU
assembly.
■ Attaching the Integral Indicator
1) Align both the LCD board assembly and CPU
assembly connectors and engage them.
2) Insert and tighten the two mounting screws.
3) Replace the cover.
Output terminal cable
Press
forward
Slide
switch
Integral
indicator
LCD board assembly
Mounting screw
Amplifier Cover
Figure 6.3 Removing and Attaching LCD Board
Assembly and CPU Assembly
6-4
Zero-
Boss
adjustment
screw
CPU assembly
Bracket
(for zero-adjustment
screw pin)
Zero-adjustment
screw pin
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IM 01C25W01-01EN