Eclipse 705 Installation And Operating Manual page 29

MAINTENANCE
TROUBLESHOOTING APPLICATIONS: Single Rod type GWR probe
Most frequent application problems that may occur, media
buildup on the probe and stratification, are covered here.
Significant buildup on the probe is not a problem in most
cases–Eclipse circuitry typically works very effectively.
• Nozzles (only for 7MF/7MH/7MJ/7M1/7M2)
Nozzles can create false echoes that can cause diag-
nostic messages and/or errors in measurement. If end
of probe high «Eop High» is displayed when first con-
figuring the instrument:
1. Ensure the probe length «Prb Ln» as entered in the
software is equal to the actual probe length (see page
12, item 9). This value must be changed if the probe
is cut shorter from the original length.
2. Increase the blocking distance «BlockDis» value
until the message is eliminated; 20 mA point may
need to be lowered.
3. Increase the dielectric range a small amount or
decrease the sensitivity to aid in reducing echoes in
nozzle. Increasing the dielectric settings may cause
instrument to lose level of lower dielectric media; con-
sult factory.
• Obstructions (only for 7MF/7MH/7MJ/7M1/7M2)
If the level reading repeatedly locks on to a specific level
higher than the current level, it may be caused by a
metallic obstruction. Obstructions in the vessel (e.g.
pipes, ladders) that are located close to the probe may
cause the instrument to show them as level.
1. Refer to the Probe Clearance Table
2. Increase the dielectric range a small amount or
decrease the sensitivity to aid in reducing disturbing
echoes in nozzle. Increasing the dielectric settings
may cause instrument to lose level of lower dielectric
media; consult factory.
• Coating/build-up (only for 7MF/7MH/7MJ/7M1/7M2)
The Eclipse 705 wih Single Rod Probe was designed to
®
operate effectively in the presence of media building up.
Some expected error may be generated based upon the
following factors:
¨ Dielectric of the media that created the coating
≠ Thickness of the coating
Æ Length of the coating above the present level
In case build up is picked up as level, increase the
dielectric range a small amount or decrease the sensi-
tivity.
• Coating/build-up (only for 7M5/7M7)
Continuous film coating is where the media forms a thin
continuous coating on the probe. Eclipse
to measure effectively with some degradation in perfor-
mance. The degradation is proportional to the dielectric
of the media and the thickness of the coating up to a
degree that the unit will see coating as a level. Higher
dielectric media (eg. water based) will show sooner as a
level at the location of the build up.
Probe clearance table
Distance to probe
< 150 mm (6")
> 150 mm (6")
> 300 mm (12")
> 450 mm (18")
will continue
®
Nozzles
• 2" diameter minimum
• Ratio of diameter: length should be > 1:1
If not, set blocking distance at 2 x nozzle height
• Do not use pipe reducers (restriction)
Obstruction
Acceptable objects
Continuous, smooth, parallel,
conductive surface (e.g. metal
tank wall); probe should not touch
tank wall
< 1"/DN25 diameter pipe and
beams, ladder rungs
< 3"/DN80 diameter pipe and
beams, concrete walls
All remaining objects
≠
Coating Build-up
Æ
¨
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