Pine Research MSR 636A, Руководство пользователя

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DRU10002 (REV 004 / JAN 2017)
the laboratory (via the “third prong”) offers a robust connection to the earth, then
this front panel connection can be used as an earth grounding point.
It is also very important to note that the chassis of the rotator control unit is in direct
contact with the earth ground connector. Thus, it is not possible to isolate the
control unit chassis from the “third prong” earth ground.
The chassis of the motor unit is also normally connected to the chassis of the
control unit, and thus, to earth ground. This connection is usually made in an
indirect fashion. Because the motor control cable (which connects the motor unit
to the control unit) is a shielded cable, the shield assures that the chassis of the
motor unit and the chassis of the control unit are electrically connected. And
because the control unit chassis is connected to earth ground, the motor unit
chassis is also in contact with earth ground.
Note:
Newer rotators have a shielded motor control cable which has HD-
15 connectors on each end of the cable. The shield line in this
cable assures that the chassis of the motor unit is in contact with the
chassis of the control unit. The chassis of the control unit is, in turn,
in contact with earth ground via the
“third prong” on the power
cord; thus, the motor unit chassis is also earth grounded.
Note:
Some older rotator models did not have a shielded motor control
cable. These older, unshielded motor control cables are easily
recognized because they are permanently connected to the
control unit. If working with one of these older rotators, it is
necessary to purposefully make a connection from the motor unit
chassis to the earth ground connection on the front panel of the
rotator control box.
4.5.3 A Typical Grounding Strategy
While the details of proper grounding for any given electrochemical experiment
may differ, a common approach when working with a rotating electrode cell is
to connect the chassis of all instruments involved in the experiment to the earth
ground at a common point. The earth ground connection on the front panel of
the rotator control box serves as a convenient common point for such a strategy.
There are two important grounding connections that should be considered in any
rotating electrode experiment.
The first important connection is to ground any metal clamps or cell supports near
the electrochemical cell (see Figure 4.12). If left ungrounded, these metal objects