Bird Technologies 8630B Series - Manual (Page 49)

Maintenance
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Model 8731-101 Load (used in Model 8631 and 8631B), 3-1/8 inch EIA
flanged and Model 8738-101 Load (used in Model 8638 and 8638B), 3-
1/8 inch unflanged input connector.
1. Loosen and remove the 3/8-16 hex nut, and the 3/8" split
lockwasher with a 9/16 socket or nut driver while holding the
center conductor stationary.
2. Remove the center conductor and the insulator, for Models 8731
and 8738.
3. Remove the resistor fitting by pushing the exposed threaded end of
the fitting into the outer flow tube. The resistor fitting and any
broken pieces of resistor will fall from the opposite end of the outer
flow tube.
4. Inspect all internal parts and O-Ring seals for damage. The metal
parts may be discolored or oxidized and may be cleaned by rubbing
them with fine abrasive cloth or silvercleaner. The Teflon parts
can be cleaned with detergent and water. If any of the internal
parts are damaged, they must be replaced to ensure proper
electrical and/or thermal performance of the load.
5. Insert the replacement resistor into the resistor fitting. If the
fitting is loose press the slotted finger contacts together slightly
and try the resistor again. Continue this procedure until a snug fit
is obtained.
6. Reassemble the input center conductor assembly by first replacing
the outer flow tube seal O-Ring, if necessary.
7. Insert the resistor fitting in position in the outer flow tube.
8. Replace insulator and center conductor for Models 8731 and 8738.
Tighten in place with the 3/8-16 hex nut and 3/8" split lockwasher.
Final Assembly 1. Replace the input center conductor assembly by lowering it into
the flanged end of the load housing assembly, and pressing it into
place.
2. Remount the outer conductor assembly, for Models 8730, 8731 or
8738, by placing the flange with the threaded holes against the
flange of the housing assembly. Tighten the six 1/4-20 x 5/8" hex
head cap screws securely.
3. Continue with the Resistor Replacement Instructions, given
earlier in this chapter.
Any maintenance or service procedure beyond the scope of those
provided in this section should be referred to a qualified service
center.