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Teledyne 4060 manual Proportional Temperature Controller PCB

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Maintenance	Series 4060

5.5.2 Proportional Temperature Controller PCB

Schematic No. B-30974 Assembly Dwg. No. B-30927

The temperature of the chamber to be controlled is regulated by a thermistor-directed electronic circuit. The thermistor and heating element are located in the chamber, and the balance of the circuit components are mounted on the temperature controller printed circuit board, which plugs into a connector on the motherboard.

The control temperature is determined by the value of resistor R3 and C3 on the temperature controller printed circuit board, selected (at the time of manufacture) from the chart on schematic B-30974 to provide the desired control point.

The thermistor used in the circuit is a negative temperature coefficient (NTC) device; as the chamber temperature increases, the resistance of the thermistor decreases, and vice versa.

The resistance of the thermistor in the circuit is compared with the value of resistor R3; when their resistance is equal, or when the resistance of R3 is less than that of the thermistor, the heating circuit is activated.

When a temperature deficiency is sensed by the thermistor, integrated circuit A1, acting as a zero-crossing switch, applies a pulsed signal to triac Q1, which in turn applies full wave power to the heating element.

IC A1 employs a diode limiter, a zero-crossing (threshold) detector, an on-off sensing amplifier (differential comparator), and a Darlington output driver (thyristor gating circuit) to provide the basic switching action. The DC operating voltages for these stages are provided by an internal power supply, with only capacitor C4 added externally.

The on-off sensing amplifier in this circuit is configured as a free- running multivibrator. This scheme adds proportional control, which takes over when the comparator inputs are at the design differential voltage.

Initially, when cold, the thermistor resistance is large, and the voltage at pin 7 is larger than that at pin 8. As the temperature of the controlled chamber begins to rise, the resistance of the thermistor decreases, thus reducing the voltage at pin 8. During this warm-up time

72	Teledyne Analytical Instruments

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Teledyne 4060 manual Proportional Temperature Controller PCB

Contents

DANGER INSTRUCTION, OPERATING AND MAINTENANCE MANUAL FORSERIES P/N M76417 DATE 06/29/10Warranty SeriesTeledyne Analytical Instruments Copyright 2010 Teledyne Analytical InstrumentsSafety Messages No SymbolThis manual provides information designed to guide you through the installation, calibration and operation of your new analyzer. Please read this manual and keep it available Additional Safety Information COMBUSTIBLE GAS USAGEDANGER Always purge the entire system before performing any maintenance and always leak check the system after removing any tubing or fittings on the sample system. See the procedures for purging and leak checking this instrument on the following pages Procedure for Removal of Internal Inaccessible Shock Hazards READ THIS MANUAL BEFORE OPERATING THE INSTRUMENT AND ADHERE TO ALL WARNINGS INCLUDED IN THIS MANUALTable of Contents 3.3 User Connections 4.5 Sample Pump 5.1.4 Collector Cable List of Figures Figure 2-1 Internal Temperature ControllersFigure 2-2 Typical Piping Diagram for the Model Figure 3-2 Equipment Interface Connector Pin ArrangementList of Tables Table 3-4 Alarm Relay Contact PinsTable 3-7 Pin out of 50 pin D-Sub Connector Table 3-8 Commands via RS-232 Input1.1 Main Features of the Analyzer Introduction1.2 Principle of Operation 1.3 Analyzer DescriptionFigure 1-1 Model 4060 Front Panel Interface Figure 1-2 Model 4060 Rear PanelSeries Introduction1.4 Applications  Gas purity certification  Detecting trace benzene in ambient air Detecting atmospheric pollutants Operational Theory 2.1 Introduction2.2 Modes of Operation 2.3 Analyzer Subsystems 2.3.1 Sample SystemFigure 2-1 Internal Temperature Controllers 2.3.2 Gas Flow Control System2.3.3 Fuel and Blanket Air Systems 2.3.4 Flame Ionization Detection CellFigure 2-2 Typical Piping Diagram for the Model SeriesOperational Theory Teledyne Analytical Instruments2.4 Detection Cell Figure 2-3 Flame Ionization Cell 2.4.1 Electrometer-Amplifier2.4.2 Anode Power Supply 2.4.3 Flame Guard Circuit2.4.4 Flame Ignition Circuit Installation 3.1 Unpacking the Analyzer3.2 Mounting the Analyzer 3.3 User Connections 3.3.1 Electrical Power Connections3.3.2 Electronic Connections Figure 3-1 Model 4060 Rear Panel with Optional Gas Manifold 3.3.2.1 PRIMARY INPUT POWERFigure 3-2 Equipment Interface Connector Pin Arrangement 0-1 VDC % of RangeTable 3-1 Analog Output Connections Table 3-2 Analog Concentration Output-ExamplePin Function ExamplesTable 3-3 Analog Range ID Output-Example Threshold AlarmTable 3-4 Alarm Relay Contact Pins Table 3-5 Remote Calibration Connections For exampleTable 3-6 Range ID Relay Connections 2. When the CRC closes, remove the span commandTable 3-7 Pin out of 50 pin D-Sub Connector 3.3.2.10 RS-232 PORTTable 3-8 Commands via RS-232 Input Table 3-9 Required RS-232 Options3.3.3 Gas Connections Figure 3-3 Gas Connections USE WATER PUMPED AIR WITH THC LESS THAN 0.1 PPM. DO NOT USE OIL PUMPED AIR UNDERANY CIRCUMSTANCES FUEL3.4 Placing the System in Operation Operation 4.1 Equipment4.2 Preliminary Power-Off Check List 4.3 Activating the Support Gases4.4 Flame Ignition 4.3.1 Air4.3.2 Carrier Gas 4.3.3 Span Gas4.5 Sample Pump 4.6 Analyzer Operation4.4.1 Verification of the Flame Guard Circuit 4.4.2 Ignition and/or Flame Guard Circuit FailureCaution ALARM SUPPRESSION Refer to the Addendum and Testing 4.6.1 Default ParametersAlarms PasswordExample Analysis Mode or Setup Mode4.6.3 Navigation and Data Entry 4.6.3.2 ENTER4.6.3.3 ESCAPE 4.6.4 Menu Structure3. MODIFIABLE ITEM screens have a flashing value somewhere in the line 4.6.5 Span Note The self diagnostics will interrupt analysis temporarily 4.6.8 System Self-Diagnostic Test4.6.6 ALT-SPAN 4.6.7 The Model Screen4.6.9 The Alarms Function AL-1 DEFEATED AL-1 HIGH AL-1 NON-FAILSAFE AL-1 NON-LATCHING AL-1 20.00 ppb AL-2 ACTIVE AL-2 LOW AL-2 FAILSAFE AL-2 LATCHINGAL-2 50.00 ppb RELEASING A LATCHED ALARM When alarm conditions are present, the main analysis screen will have one or both of the following messages AL-1, AL-2 followed by the instruction ENT/ACK . Pressing ENTER will release a latched alarm. That is, if there will not be an alarm condition until the analysis concentration is again violating the trip point. Furthermore, the alarms will be suppressed until the analysis value is updated, so even though the screen may be reporting a value that should cause an alarm, until the analyzer again enters SAMPLE MODE, no alarm condition will reoccur 4.6.11 Analog Output Adjustment 4.6.10 The Range FunctionRange Select Man Man Rng R1 R1 0-100.00ppb R2 0- 1.00ppm R3 0- 10.00ppmNote Before setting up an AUTOCAL, be sure you understand 4.6.14 Setting up an AUTO-CAL4.6.12 Linearization 4.6.13 Changing StreamAUTOCAL PASSWORD AS3d 20h AUTO SPAN Enabled Span in 11 days Span in 6 hours4.6.16 Group Setup 4.6.17 Password Protection4.6.15 Timing ENTERING A PASSWORD PASSWORDENTER PASSWORD SCREEN CHANGE PASSWORD SCREENENTER NEW PASSWORD SCREEN REPEAT PASSWORD ENTRY SCREEN 4.6.18 Logging OutRestrict Access? ENTER=Yes ESCAPE=NO 4.6.19 StandbyEnter Pressing Enter places the instrument in STANDBY Operation SeriesTeledyne Analytical Instruments Maintenance & Troubleshooting Work with one hand only5.1 Measuring Circuit Electrical Checks 5.1.1 Anode Voltage Check5.1.3 Printed Circuit Board Replacement 5.1.2 Electronic Stability5.2 Temperature Control Electronic Check 5.1.4 Collector Cable5.3 Ignition and/or Flame Guard Circuit Checks 5.4 Sampling System 5.5 Printed Circuit Board Descriptions 5.5.1 Flame Guard and Anode Power Supply PCB5.5.2 Proportional Temperature Controller PCB 5.5.3 Electrometer-Amplifier PCB The stability of the electrometer circuit can be tested as follows A.1 Specifications and Initial Settings AppendixA.2 Recommended Spare Parts List Analytical InstrumentsA.3 Drawing List PC Board AssembliesAppendix SeriesTeledyne Analytical Instruments B1 Addendum and Testing Results Appendix B