By-Pass | Teledyne 3000ZA-3X instruction

Trace Oxygen Analyzer	Maintenance

(including the cell) the pressure will be at atmospheric pressure (analyzer vented to atmospheric pressure). Note, all other pressure drops in the sample path are insignificant at these flow rates. This insures that the cell operates at atmospheric pressure. At very high flow rates (off scale of flow-meter), pressure drops other than the restriction device could become significant, and result in pressurizing the cell.

Example 2: A 3000TA is configured for vacuum service as follows. The unmarked restrictor is placed in the sample vent port. The downstream end of the restrictor is then connected to a vacuum pump and by-pass valve. The by-pass valve is adjusted to provide a flow rate of 1 SLPM. The sample pressure between the pump and the restrictor will be approximately -7 inches of mercury, while the pressure in the balance of the sample system including the cell will be approximately at atmospheric pressure (provided the sample flow into the analyzer is not blocked).

BY-PASS:

To improve the system response, a by-pass can be added to increase the sample flow rate to the analyzer by a factor of ten. A by-pass typically provides a sample flow path around the analyzer of 2 - 18 SCFH.

CALIBRATION GAS:

3000 series analyzer requirements for units with Auto-Cal options are as follows:

The customer must supply control valves (or restrictors) for any SPAN or ZERO gas source which is attached to the Auto-Cal ports. The valve should be adjusted to the same flow rate as the sample gas. When restrictors are used, the gas pressure must be adjusted to achieve the proper flow rate.

OPERATION WITHOUT A RESTRICTOR DEVICE:

Operation without a restrictor device is not recommend as mentioned above. A 3000TA without any flow restrictor device was tested on 11-19-97. This results in a flow rate of 2.4 SLPM @ 1 PSIG. This is a cv of 0.023 for the standard sample system.

REFERENCE: FLOW_1.XLS & FLOW_2.XLS for information on flow rates at various pressures.


Teledyne Analytical Instruments	59

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Teledyne 3000ZA-3X operating instructions By-Pass

Contents

Model 3000ZA-3X 3000ZA-3X Specific Model Information Important Notice Safety Messages 3000ZA-3X Vii Table of Contents Testing the System Appendix Maintenance Model 3000ZA Rear Panel Model 3000ZA Front Panel Xii List of Tables Typical Applications Main Features of the AnalyzerIntroduction Overview Introduction 3000ZA-3X Model Designations Model 3000ZA Front Panel Front Panel Operator Interface Alphanumeric Interface Screen Function KeysData Entry Keys Digital Meter Display Standby Button Access DoorRear Panel Equipment Interface Optional ∙ 50-Pin Equipment Interface Port Principles of Operation Operational TheoryIntroduction ZrO2 Sensor Operational Theory 3000ZA-3X Sample System Zirconium Oxide Sensor Application Notes Electronics and Signal Processing Operational Theory 3000ZA-3X Component Location Electronic Block Diagram Mounting the Analyzer InstallationUnpacking the Analyzer Installation 3000ZA-3X Gas Connections Rear Panel Connections Installation3000ZA-3X Electrical Connections Zero in and Span in Optional Equipment Interface Connector Pin Arrangement Analog Output Connections Threshold Alarm Alarm Relay Contact Pins System Alarm Remote Calibration Connections Range ID Relay Connections Remote Probe Connections 2.3 RS-232 Port FET Series Resistance Commands via RS-232 Input Testing the System Installing the Zirconium Oxide Sensors Operation Keys Description Using the Data Entry and Function ButtonsStyle Conventions Escape Enter System Menu Menu/Screen StructureAnalyze Screen Hierarchy of Available Functions Enter New Password T a Password routineEnter Password T a Change Password Model Routine Logout Routine Filter Routine Analog-Out Adjust RoutineSelf-Test Routine 20mA Gain 20mA Limit False Track in Cal Yes Change Stream Auto-Calibration TimerSpan Menu Span Value Span TimerSpan Sensor Span Begin Begin Span? Span FinishSpan Auto Finish Span Begin Zero Value Zero MenuZero Finish Zero Begin Begin Zero? Zero TimerZero Timer 7 min Zero Begin AL-1 NON-LATCHING AL-1 20.00 ppm AL-2 Active Alarms MenuAlarm Active Alarm Polarity AL-1 80.00 ppm Alarm FailsafeAlarm Latching Alarm Setpoint Range Select Auto Range MenuRange Select Range Setpoints Manual Range Select Removing the Sensor MaintenanceRoutine Maintenance Sensor Replacement Maintenance 3000ZA-3X Sensor Block with Middle Sensor Installed Fuse Replacement Self-Test Result Display System Self Diagnostic Test Rear Panel Removal Remove only those screws marked with an Major Internal Components Troubleshooting Cleaning Trace Oxygen Analyzer Maintenance Maintenance 3000ZA-3X Teledyne Analytical Instruments Appendix Specifications Operating Temperature 5-35 C Qty Part Number Description Recommended 2-Year Spare Parts List 19-inch Relay Rack Panel Mount Drawing List Flow Rate Recommendations Application Notes Restriction Devices BY-PASS Conversions