User's Manual Part 3

♦353♦ MEGAM.O.L.E.® Help System Guide
6.2. MEGAM.O.L.E.®
This section describes problems that can occur with M.O.L.E. profiler hardware.
Hardware Problems:
Wrong or erratic temperature readings:
• Open or intermittent thermocouple, cable, or connector: Individual channels
being detected as “Open” on the profile plot will indicate this. Check
thermocouple wires and insulation. Also, check the connectors visually for
damage or loose connections. Tighten all the connections and check with an
ohmmeter or millivolt meter if available or substitute a thermocouple that you
know works properly.
• Shorted thermocouple, cable, or connector: This is harder to find. A shorted
thermocouple connector or cable creates a new thermocouple junction at the
location of the short; therefore, actual temperatures are recorded, but not the
ones desired. If the short is intermittent, the recorded temperatures may jump
between that of the thermocouple and that of the shorted location. Visually check
for shorts inside of connectors and for damaged insulation on the wires. Repair
or replace any suspicious components.
• Wrong type thermocouple, connector, or wire: Wrong thermocouple types will
give consistently wrong readings, either always high or always low. Wrong
connectors or wrong wire types (used as an extension) create extra
thermocouple junctions and uncontrolled temperature offsets. Use only Type K
thermocouple wires, and connectors.
• Thermocouple connector wired backwards: Typically causes high
temperatures to read as negative (e.g., -150°F.). Should be Yellow=Ch, Red=Al.
• Low power pack charge: Charge the power pack.
• Conductive contamination inside the M.O.L.E. profiler or I/O Module:
Although unlikely, this is known to cause “spikes” (abrupt jumps in value) in the
recorded temperatures. Other kinds of errors are also possible.
• Incorrect calibration: If the recorded temperatures for all of the active channels
are wrong in the same direction (e.g., all too high), then possibly the I/O Module
has incorrect calibration. Refer to topic Service>MEGAM.O.L.E.>Calibration
Information for cautions and procedures, or return the M.O.L.E. profiler to ECD
for re-calibration.
• Internal temperature effects: If the M.O.L.E. profiler and it's components has
been subjected to an internal temperature in excess of the published
specifications. Temperatures outside the specified operating range may cause
incorrect readings and shorten Power Pack life. Internal temperatures in