Shimadzu GC-2014 Service Manual

Chapter 7 Troubleshooting
GC-2014 Service Manual
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7.1.1.4 Precautions for Flowrate Control Settings (DetAPC)
(1) The pressure or flowrate fluctuates.
 Check that [I time] = "10", [P term] = "50", and [I term] = "20".
If not, enter these values and press the pf4 key to write them in the ROM.
 Check that the source pressure is not fluctuating.
 If the source pressure is shared (e.g., the helium carrier gas is used for the
detector's make-up gas and carrier gas), check for pressure fluctuations in
the other line.
(2) The pressure or flowrate is lower than the setting.
 Check for leaks in the line.
 Check that the source pressure (i.e., the primary pressure) has attained a
sufficient level.
 Check that [I time] = "10", [P term] = "50", and [I term] = "20".
If not, enter these values and press the pf4 key to write them in the ROM.
 Check the [Offset] and [Gain] values for the pressure.
The offset value is normally in the range 32,000 to 33,500 and the gain
value is normally in the range 3,000 to 10,000. If the offset value is well
outside this range, perform offset calibration. (The method is described in
the GC-2014 instruction manual.) If the gain value is well outside this range,
obtain the correct value from Shimadzu Corporation's Quality Assurance
Department. At this time, provide notification of the serial number and lot
number displayed on the side of the AFC.
 Check the settings to confirm that, for example, APC is not off and that the
ignition operation has not been forgotten.
If "0" is displayed as the valve voltage, this indicates that there is no voltage
being supplied from the control system to the valve that is attempting to
supply gas.
(3) The pressure or the linear velocity is higher than the setting.
 Check that [I time] = "1", [P term] = "50", and [I term] = "20".
If not, enter these values and press the pf4 key to write them in the ROM.
 Check the [Offset] and [Gain] values for the pressure.
The offset value is normally in the range 32,000 to 33,500 and the gain
value is normally in the range 3,000 to 10,000. If the offset value is well
outside this range, perform offset calibration. (The method is described in
the GC-2014 instruction manual.) If the gain value is well outside this range,
obtain the correct value from Shimadzu Corporation's Quality Assurance
Department. At this time, provide notification of the serial number and lot
number displayed on the side of the AFC.
Also, it may be possible to stop fluctuation by changing the P term or the I term (to a
value several times, or a fraction of, the original value). Use this method to stop
fluctuation in urgent cases.

Shimadzu GC-2014 Specifications

General

Type	Gas Chromatograph
Display	LCD
Maximum Heating Rate	120°C/min
Data Acquisition	Digital
Maximum Number of Detectors	4
Weight	Approx. 45 kg
Carrier Gas	Helium, Nitrogen, Hydrogen
Detector Options	FID, TCD, ECD, FPD
Injection Port	Split/Splitless, On-column
Gas Control	Electronic Flow Control (EFC)
Temperature Programming Rate	0.1 to 120 °C/min
Power Requirements	230 V AC, 50/60 Hz
Detector Temperature Range	Up to 400°C (depending on detector type)