Cole Parmer 16 Series, Руководство по эксплуатации

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TROUBLESHOOTING
Display does not come on or is weak.
Check power and ground connections and supply voltage.
Pressure reading is approximately fixed either near zero or near full scale regardless of actual
line pressure.
The pressure sensor may be damaged. Damage due to excessive pressure is not covered by
warranty.
Displayed pressure is flashing and message POV is displayed:
Our pressure gauges and controllers display an error message (POV = pressure overrange) when a
the pressure exceeds the range of the sensors in the device. When any item flashes on the display, the
pressure measurement is not accurate. Reducing the pressure to within specified limits will return the
unit to normal operation and accuracy.
My controller does not respond to the set-point.
Check the control set up screen to be sure the Input parameter selection matches the set-point you
are trying to use. Also, be sure that the unit was ordered for the type of analog signal you are trying to
use.
After installation, there is no pressure.
Cole-Parmer PC Series Controllers incorporate normally closed valves and require a set-point to
operate. Check that your set-point signal is present and supplied to the correct pin and that the correct
input is selected under the Input list in the control set up mode screen. Also check that the unit is
properly grounded.
The pressure lags below the set-point.
Be sure there is enough pressure available. If either the set-point signal line and/or the output signal
line is relatively long, it may be necessary to provide heavier wires (especially ground wiring) to negate
voltage drops due to line wire length. An inappropriate PID tuning can also cause this symptom if the D
term is too large relative to the P term.
Controller is slow to react to a set-point change or imparts an oscillation to the flow.
An inappropriate PID tuning can cause these symptoms. Use at conditions considerably different than
those at which the device was originally set up can necessitate a re-tuning of the PID loop. Note: The
larger the volume pressured, the longer it takes to change the pressure in that volume.
The output signal is lower than the reading at the display.
This can occur if the output signal is measured some distance from the gauge/controller as voltage
drops in the wires increase with distance. Using heavier gauge wires, especially in the ground wire, can
reduce this effect.
My controller oscillates wildly and/or exhibits very different reactions to the set-point than I
expect.
Conditions considerably different than those at which the device was originally set up can necessitate
a re-tuning of the PID loop.
RS-232 Serial Communications is not responding.
Check that your gauge is powered and connected properly. Be sure that the port on the computer to which
the gauge is connected is active. Confirm that the port settings are correct per the RS-232 instructions
in this manual (Check the RS-232 communications select screen for current gauge readings). Close
HyperTerminal® and reopen it. Reboot your PC.