RJG 211M18, Product Manual

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Product Manual | Piezoelectric Load Washer Sensor 211M18 17
MAINTENANCE
CLEANING & DRIFT
REGULAR CLEANING
Pull sensors from the mold and clean out
the pockets and channels when a mold
is pulled for preventative maintenance.
Sensors must be installed in pockets free
from oil, dirt, grime, and grease.
RJG, Inc. recommends the following
cleaners:
• MicroCare MCC‑CCC Contact Cleaner C
• MicroCare MCC‑SPR SuprClean™
• Miller‑Stephenson MS‑730L Contact
Re‑Nu®
DRIFT
Piezoelectric sensors can drift negative
(‑) or positive (+). The acceptable drift
specification for RJG piezoelectric sensors
is 20 pC/minute. The easiest place
to monitor this is the eDART “Sensor
Locations” screen. Drift of ±20 pC in
sixty seconds indicates abnormal drift.
The cause of “Drift” is dirty/contaminated
connections. This could be the connection
at the sensor to cable or cable to adapter
case.
Properly clean all connection points with
an electronics grade contact cleaner. Allow
the sensors and cables to air‑dry before
reconnecting them. Do not blow them out
with a “shop” air line as this air usually
contains oil and other contaminants.
If drift continues, clean the sensors out
again with electronics grade cleaner
then bake them in an oven to remove the
contaminants (same method used at RJG).
It is recommended to bake the sensors/
cables at 100 ºC for sixty minutes.
If continuing to experience drift after this,
please contact RJG Sales for pricing and
lead time on replacement items.
TESTING & CALIBRATION
SENSOR TESTING
1. Sensor PreCheck
The Sensor PreCheck provides diagnostics
on typical sensor problems such as sensor
drift, preload, and zero shift, and can also
detect sensor installation errors caused
by improper pocket dimensions, damaged
wires, and damaged sensor heads. A test
report with sensor configuration can be
emailed or printed from the device. This
device allows testing of up to thirty‑two
sensors at one time and can verify that a
force was applied to the sensor.
2. eDART Software—Raw Data Viewer
The eDART Raw Data Viewer displays the
status of the sensor, either Valid, No Reply,
Stale, or Invalid.
• A Valid sensor has raw counts that
change when force is applied to the
sensor; this indicates a properly working
sensor.
• A No Reply sensor is not communicating
with the eDART; the sensor may be
unplugged.
• A Stale sensor indicates a sensor that is
unused.
• An Invalid sensor will indicate a Failure of
either Over‑range (Ovrng) or Under‑range
(Undrng). The Ovrng indicates the
sensor’s calibration has changed too
far in a positive direction, outside of the
upper specification. The Undrng indicates
that the sensor’s calibration has changed
too far in a negative direction, and the
sensor may report a number below zero
when load is applied.