FDI P2131, Техническое руководство, Страница: 90 / 161

4.3.1 Replacing the HTS ‐ 1 RTD Sensors
1. Turn OFF the SMU, disconnect power, and ensure pressure in the chamber and jacket is
at 0 psig.
2. Remove the Back Lower Panel, Heater Assembly Cover, and Heater Block Enclosure by
removing 10 pan head screws. (Reference Section 4.3.17)
3. Disconnect the 3 incoming heater wires by using 3/8” wrench to counter ‐ torque and 3/8”
socket to loosen nuts. Heater element nuts are torqued to 35 in ‐ lbs.
4. Disconnect the white RTD Connector in bottom of heater box.
5. Remove 8 white heater stud caps (After S/N’s AFS ‐ 0340).
6. Remove the 8 heater plate nuts with a 9/16 socket. Remove the lock, flat, and isolation
washers. The heater plate nuts are torqued to 120 in ‐ lbs.
7. Use a rubber mallet to pry the heater plate away from the heater flange.
8. Slide the Heater Element Assembly out of the jacket.
9. Compress the springs and slide the springs off the end of both RTD’s.
10. Remove both RTD’s by loosening Swagelok nut and sliding out. Discard old RTD’s.
11. Install new RTD’s by inserting into Swagelok fitting and tightening nut finger tight then
1/4 turn. The long RTD is installed in the right fitting, on right leg of center heater element.
The short RTD is installed in the center fitting, on left leg of center heater element.
12. On the long probe, compress and slide a spring to the center of the probe. On both the
long and short probe, compress and slide the springs over the end of the RTD’s until
approximately 3/8” of the RTD probe extends beyond the spring.
13. Reinstall Heater Element Assembly by following steps 1 ‐ 4 in reverse order. Ensure
isolation bushings are reused. Ensure blue isolation washers are reused.
NOTE : Always reuse the blue isolation washers against heater plate when reinstalling
heater plate.
Isolation Bushings
RTD’s
S/N’s AFS ‐ 0001 through 0286
Wiring Configuration
S/N’s after AFS ‐ 0286
Wiring Configuration
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