Thermo Scientific RO-20, Operating Manual

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4-4 RB-XXX-XXXXXX E RO-20
Löw 08.10.2008
Caution The three 12V alkaline batteries holds the circuit components at 36 volts negative
with respect to the chassis. Never short any circuit point to chassis or damaged components
may result.
To remove the chamber face:
1. Pry off the clamp ring and lift off the face.
2. To remove the chamber assembly, push the desiccant package toward the rear and
separate the hose from the desiccant package.
3. Loosen (or remove) the four screws holding the chamber and rotate it until it is free.
4. Unplug the cable from the chamber. When the chamber’s electronic section is
exposed, it is best to short the center pin of the guarded feedthrough to the guard ring
to prevent static damage to the amplifier.
Caution Never short any part of the chamber circuit to the chamber body or damage to the
components may result. ▲
To remove the small battery/connector board from the chamber:
1. Remove the two screws and gently pull the board from the chamber.
2. As soon as the cable connector can be reached, hold it and unplug it from the
connector board. (Handle the cable gently.)
3. Remove the board.
To remove the center electrode disk from the chamber:
1. Gently unplug the cable between the chamber board and the small battery board.
Unplugging the cable removes the 36-volt bias between the disk and the chamber
walls.
2. With pliers, hold the center pin in the electronics section to keep it from turning and
unscrew the disk. Two small holes in the disk are provided to help rotate it.
To remove the chamber board assembly:
1. Gently unplug the cable that connects the assembly to the battery board.
2. Unsolder the connections to the guarded feedthrough assembly.
3. Remove the three nuts holding the board and lift it out.