MJ Research PTC-0200, Operation Manual

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Operation
material can interfere with the proper seating of a microplate or tubes,
which would prevent the inner lid from exerting uniform pressure
on the loaded microplate or tubes.
2. Open the Hot Bonnet. Turn the blue thumbwheel all the way counter-
clockwise to completely raise the inner lid.
3. Load either a microplate or at least eight individual tubes into the
sample block. The inner lid pivots around a central point, so it is im-
portant to distribute individual tubes evenly: Load at least four tubes
in the center of the block and at least one tube in each of the four
corners of the block. If using a sealing film or mat, apply it to the
loaded microplate according to the manufacturer’s directions.
4. Close the Hot Bonnet by pressing down on the top lever. Turn the
thumbwheel clockwise to lower the Hot Bonnet’s inner lid onto the
loaded microplate/tubes. The thumbwheel turns easily at first since
the inner lid has not yet come into contact with anything. Stop turn-
ing the thumbwheel when you feel increased resistance, which indi-
cates that the inner lid has touched the microplate/tubes.
5. Open the Hot Bonnet. Turn the thumbwheel clockwise an extra half
to three-quarters of a turn to set an appropriate lid pressure.
Caution: Caution:
Caution: Caution:
Caution: Do not turn the thumbwheel more than three-quarters of a
turn. This can make it hard or impossible to close the lid
and puts excessive strain on the latch holding the lid closed.
An extra half to three-quarters of a turn ensures the correct pressure for
most types of reaction vessels. Some empirical testing may be required
to determine the optimum pressure required for certain vessels. Once
this pressure has been determined, the thumbwheel position that deliv-
ers it may be marked with a colored marking pen or piece of tape.
Note: Note:
Note: Note:
Note: As an aid in gauging how much the thumbwheel has been
turned, mark it at the quarter turn positions, or every sixth “bump”
on the thumbwheel (there are 24 total “bumps”).
6. Close the Hot Bonnet.
Loading Sample Vessels into the Block
When using a small number of tubes, they should all be placed in the
center of the block, to ensure uniform thermal cycling of all samples. Also
load at least one empty tube in each corner of the block, to ensure that the
Hot Bonnet exerts even pressure on the sample tubes (see “Adjusting the