705-5100-111 Datasheet, PDF (4/28 Pages) Magnetrol International, Inc. – Eclipse® Enhanced Model 705 Guided Wave Radar Level Transmitter

PROBE OVERVIEW
SINGLE ROD PROBES
Single element GWR probes act quite differently from Coaxial and
Twin element designs. The pulses of energy develop between the
center rod and the mounting nut or flange; the pulse propagates
down the rod as it references its ground at the top of the tank. The
efficiency of the pulse “launch” is directly related to how much
metallic surface exists around it at the top of the vessel.
Figure 3 shows the single element design and how the pulse
expands into a teardrop shape as it propagates away from the top
of the tank (ground reference). This Single element configuration
is the least efficient of the three with minimum dielectric detection
approximately ε_r > 10. This dielectric performance improves con-
siderably (ε_r > 1.9) when the probe is installed between 2–6"
(50–150 mm) of a metal tank wall or in a cage/bridle. Because the
design is the “open”, it exhibits two strong tendencies. First, it is
the most forgiving of coating and buildup. (The PFA-insulated
probe is the best choice for severe coating). Secondly, it is most
affected by proximity issues. It is important to note that a parallel
metal wall INCREASES its performance while a singular, metal
object protruding near the probe may be improperly detected as a
liquid level.
HYGIENIC MODEL 705
Eclipse 705 is available with a deep drawn housing and a 0.4 µm
(RA 15) finished single rod GWR probe for use in ultra clean envi-
ronments.
For more details – refer to bulletin 57-110.
Figure 3
Single Rod Probe
3_{⁄4" Hygienic Connection without bend}
0.25 inch diameter probes suitable for use in smaller
vessels where space is at a premium. Available in
lengths up to 72 inches.
1¹â„2" Hygienic Connection with bend
316 SS probes can be bent to avoid internal obstructions
such as agitator blades and spray balls, and to insure
lowest possible level detection.
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