Metek RCT 10 series, Инструкция по установке и эксплуатации

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Installation
7
2.3 Mounting the Electronic Unit (Continued)
The mounting location for the sensing element is often
determined by whether there is a suitable location inside
a vessel. An external side arm or stilling well can be
considered.
The following sensing element mounting and installation
instructions should be followed so that the equipment will
operate properly and accurately:
A. In applications requiring an insulated sensing
element, use particular care during installation.
There is always the danger of puncturing the
insulation, especially with the thin-walled sensing
elements.
B. Sensing elements should be mounted in such a
manner that they are not in the direct stream of
a filling nozzle or chute. If this is not possible, a
deflecting baffle should be installed between the
sensing element and the fill.
C. Do not take the sensing element apart or loosen the
packing glands. Follow instructions in Figure 2-3 .
D. Avoid installing the sensing element with any of
the common mistakes shown in Figure 2-4.
E. If a stilling well is used, ensure that "vent" holes
are large enough to allow free passage of both
air and process material. Holes should be 5/8" or
larger, 120
o
apart, every 2-3 feet along the length of
the stilling well.
F. Sensing elements that are mounted in agitated
vessels usually require brackets and supports to
control the position of the sensing element during
agitation. See Figure 2-5.
G. For non-metallic vessels without Drexelbrook self-
grounding sensing elements, choose one of the
grounding recommendations shown in Figure 2-6.