Fisher-Rosemount 3095FT, Руководство пользователя

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5-15
Troubleshooting and Maintenance
Connecting the Electrical
Housing to the Sensor 7. Remove the cable connector from its position inside the internal
shroud, and attach the cable to the electronics board.
8. Align the post-receptacle connectors with the posts inside the
electronics housing.
9. Insert the electronics board into the housing and tighten the
captive mounting screws.
10. Replace the electronics housing cover. Metal to metal contact is
preferred.
Reassembling the Process
Sensor Body 11. Visually inspect the Teflon sensor module O-rings. If the O-rings
are undamaged, they may be re-used. If the O-rings show signs of
damage, such as nicks or cuts, or if there is any doubt about their
sealing ability, replace them with new O-rings. Use the following
steps:
a.Remove the damaged O-rings by carefully prying them from the
O-ring grooves. Take care not to damage the surface of the
isolating diaphragm during this process.
b.Replace the damaged O-rings by fitting new O-rings into the
O-ring grooves.
12. Install the process flange on the sensor module. To hold the
process flange in place, install the two hex head alignment
screws. These screws are not pressure retaining and need only be
finger tight. Do not overtighten; this will affect the module/flange
alignment.
13. Install the appropriate flange bolts using Figure 4-4 as a
reference:
• For installations requiring a
1
/
4
–18 NPT mounting, install the four
1.75-inch process flange bolts. First finger-tighten the bolts. Then
tighten the bolts incrementally in a cross pattern until they are
securely tightened to 650 in-lb (300 in-lb for stainless steel bolts).
After tightening, the bolts should protrude through the top of the
module housing.
• For installations requiring a 1 /
2
–14 NPT mounting, hold the
optional flange adapters and flange adapter O-rings in place
while finger-tightening the four 2.88-inch process flange/adapter
bolts. Tighten the bolts in a cross pattern following the procedure
outlined above. (Use two 2.88- inch bolts and two 1.75-inch bolts
for gage pressure configurations.) After tightening, the bolts
should protrude through the top of the module housing. If the
bolts do not extend all the way through the module housing, you
have used a bolt of incorrect length. Replace the bolt with one of
the correct length, and repeat the procedure.
Explosions can cause death or serious injury. Both
transmitter covers must be fully engaged to meet explosion-
proof requirements.