Emergency Locking
3 Emergency Locking
3.1 Equipment Required
You will require the following:
1. A clean environment in which to work, including suitable ESD equipment
(dissipative surface, wristband, etc.);
2. A 2mm hexagonal driver;
3. A medium-sized, flat-bladed screw-driver;
4. A soldering iron; and
5. A permanent marker.
3.2 Sensor disassembly.
Caution:
Seismometers and accelerometers contain extremely sensitive
mechanical components. Only open the casing of an instrument in a
clean environment and take precautions to prevent any ingress of dust
into the body of the instrument.
Caution:
The circuit boards contained within the instrument include
components which can be damaged by electrostatic discharge. Always
work on a properly grounded dissipative surface and wear a suitable
grounded wristband. Ground yourself by touching an earthed conductor
before handling any of the circuit boards.
To gain access to the sensor components, it is first necessary to remove the lid of the
instrument, along with any associated electronics, and the outer sleeve.
The instrument lid is secured using a number of small screws located around the top,
outside edge. The lid extends a short way down inside the cylindrical casing and
two 'O'-rings provide sealing between the lid and the cylinder. The seal thus formed
can make it difficult to remove the lid due to the differential pressure between the
inside and the outside of the casing. A pressure-relief screw is provided for this
reason.
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Issue B - January, 2017
