Lake Shore Cryotronics 121, Руководство пользователя

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14 CHAPTER 2: Installation
2.7.5 Lowering Measurement Noise
Good instrument hardware setup technique is one of the least expensive
ways to reduce measurement noise. The suggestions fall into two cate-
gories: (1) do not let noise from the outside enter into the measurement,
and (2) let the instrument isolation and other hardware features work to
their best advantage. Here are some further suggestions:
D
Do not connect sensor leads to earth ground or chassis
D
Use twisted shielded cable outside the cooling system
D
Attach the chassis to the cable shield and to earth ground if possible
D
Use twisted wire inside the cooling system
D
Consider ground strapping the instrument chassis to other instru-
ments or computers
D
Tie all ground points at one common point to avoid ground loops
D
For demanding applications, the display can be turned off
2.8 Rack Mounting
The Model 121 can be easily mounted using the panel mount brackets
included. The Model 121 fits in a 91 × 44 mm (3.6 × 1.7 in) cutout. To
panel-mount the instrument, unplug the unit and use a
1/bg
-inch hex
wrench to remove the two set screws holding the brackets in place.
Remove the two panel mount brackets by sliding them towards the rear
of the unit. Place the unit into the panel cutout. Slide the two panel
mount brackets back into the case of the instrument. Reinstall the two
set screws and tighten them until the instrument is secure.
FIGURE 2-7 Rack mounting