Omega 865, User Manual

Page 1: ...http www omega com e mail info omega com User sGuide Model 865 and 866 Digital Thermometers ...

Page 2: ...ree in France 0800 4 06342 e mail france omega com Germany Austria Daimlerstrasse 26 D 75392 Deckenpfronn Germany Tel 49 07056 3017 FAX 49 07056 8540 Toll Free in Germany 0130 11 21 66 e mail germany omega com United Kingdom 25 Swannington Road P O Box 7 Omega Drive ISO 9002 Certified Broughton Astley Leicestershire Irlam Manchester LE9 6TU England M44 5EX England Tel 44 1455 285520 Tel 44 161 777...

Page 3: ...2 Operating Procedures 2 3 2 1 Model 865 2 3 2 2 Model 866 3 SECTION 4 THEORY OF OPERATION 4 SECTION 5 SERVICE INFORMATION 6 5 1 Performance Accuracy Check 6 5 2 Disassembly 7 5 2 1 Special Handling of Static Sensitive Devices 7 5 2 2 Disassembly Instructions 8 5 2 3 Battery Replacement 10 5 3 Calibration 10 5 4 Troubleshooting 11 5 4 1 DC Voltage Checks 12 5 4 2 A D Measurements 12 5 4 3 Waveform...

Page 4: ...C on one range with a resolution of 0 1 C 1 2 FEATURES High Accuracy Resolution Repeatability to 0 1 Highly Versatile Many applications with different probe configurations probes not supplied Continuous Automatic Linearization Dual slope A D Warning Indication Overrange Open Sensor Low Battery Long Life Battery 9 V Alkaline MN 1604 Rugged Construction Heavy Duty ABS Plastic Housing SECTION 2 BEFOR...

Page 5: ...temperatures are given in the optional accessories section Do not touch the probe tip when measuring excessively high or low temperatures 3 2 OPERATING PROCEDURES 3 2 1 Model 865 See Figure 3 1 1 Turn power on by selecting the desired range 2 Insert appropriate temperature probe into the input jack 3 Touch the probe tip to the material to be measured and read the display in degrees Fahrenheit NOTE...

Page 6: ...jack 3 Touch the probe tip to the material to be measured and read the display in degrees Celsius NOTE An open sensor is indicated by a reading on the display of greater than 100 0 Overrange is indicated by blanking of the three least significant digits Low battery 10 life remain ing is indicated by LO BAT on the display 3 Figure 3 1 Model 865 Control Layout ...

Page 7: ...ows through the sensor is inversely proportional to the resistance of the sensor Ohm s Law U104B and associated resistors minimize the on resistance of the gates of U101A and B The input signal must be conditioned by the Log Ratio amplifier before being digitized by the A D converter The Log Ratio amplifier operates on two phases the signal phase and the zero phase Each phase has a duration equal ...

Page 8: ...nnected from the sensor and connected to a zero reference resistor RZ The current that flows through RZ also flows in the collector of Q101 The output voltage of U104C is connected REF LO on U102 by way of C106 and U103B see Schematic Diagram 866 106 or 865 106 The voltage that is applied to the input of U104A and across C111 is the difference between the output voltage of U104C and the voltage th...

Page 9: ...hown in Figure 5 1 2 Follow Table 5 1 to verify instrument performance NOTE The LO of the resistance box must be connected to the LO sleeve of the 0 phone jack The HI of the resistance box must by connect ed to the HI tip of the 0 phone jack Figure 4 2 Zero Phase Figure 5 1 Calibration Setup ...

Page 10: ...erminals pins etc 4 PC boards must be grounded to bench while inserting devices 5 Use anti static solder suckers 6 Use grounded tip soldering irons 7 After devices are soldered or inserted into sockets they are protected and normal handling can resume Step Setting Decade Resistance Allowable Reading 1 200 F 75 750 ohms 39 4 to 40 6 2 200 F 255 700 ohms 68 8 to 71 2 3 200 F 19 220 ohms 00 5 to 00 5...

Page 11: ...the case above the display and gently lifting it away from the display 3 Remove the battery 4 Remove the standoff that secures the PC board to the case It is located in the center of the PC board 5 Remove the switch cover for the Model 866 and for the Model 865 6 Lift the PC board out of the top cover front panel When removing the LCD from the PC board be careful not to spread the four retaining h...

Page 12: ...n reassembling the instrument be sure to reinstall the switch cover Common mode voltage may be present on the switch creating a hazard if the cover is not reinstalled 9 Figure 5 2 Models 865 and 866 Exploded View ...

Page 13: ...he instrument off and remove the input probe from the instrument before remov ing the bottom cover Figure 5 3 Battery Installation 5 3 CALIBRATION Calibration should be performed yearly or whenever the performance verification procedure indicates that the instrument is out of specification under laboratory conditions having an ambient temperature of 23 C63 C and a relative humidity of less than 80...

Page 14: ...p the equipment as shown in Figure 5 1 2 Turn on the instrument 3 Perform calibration refer to Table 5 2 or Table 5 3 as applicable 4 Verify correct calibration Refer to paragraph 5 1 performance accuracy check 5 Reinstall the bottom cover Step Range Input Adjustment Reading A 200 F 19220 ohms R111 00 0 6 0 counts B 200 F 220 8 ohms R110 190 0 6 0 counts C 300 F 43 ohms R112 300 6 0 counts D R110 ...

Page 15: ...the Model 865 and 150 C for the Model 866 NOTE All the measurements in steps 2 through 5 are referenced to analog common 2 Measure the voltage at U102 pin 31 IN HI and record the value 3 Measure the voltage at U102 pin 30 IN LO and record the value 4 Measure the voltage at U102 pin 35 REF LO and record the value 5 Measure the voltage at U102 pin 36 REF HI and record the value 6 Calculate the displ...

Page 16: ...cks in Table 5 5 13 Step Item Component Waveform 1 Referenced to analog ground U102 pin 40 OSC 1 2 U102 pin 39 OSC 2 3 U102 pin 38 OSC 3 Same as step 2 4 U102 pin 27 INTEGRATOR with negative full scale input of approximately 1900 counts 5 U102 pin 21 Backplane TABLE 5 5 WAVEFORM CHECKS ...

Page 17: ...18 TO 28 F 1 year 150 F 40 0 to 150 0 0 1 6 0 3 rdg 0 3 C 55 0 to 40 1 0 1 6 0 3 rdg 0 6 C ACCURACY Includes repeatability temperature coefficient 65 to 82 F time stability 1 year and linearization conformity errors Excludes probe errors how ever probe errors around 32 F may be compensated by an internal adjustment REPEATABILITY 0 2 F typical for 1 week at constant ambient temperature TEMPERATURE ...

Page 18: ...igit LCD O 5 13 mm height Polarity and decimal point indication CONVERSION RATE 1 5 readings per second OPEN SENSOR INDICATION Display reads between 100 and 199 OVERRANGE INDICATION 3 least significant digits blanked MAXIMUM COMMON MODE VOLTAGE 42 V peak to earth COMMON MODE REJECTION Model 865 Less than 0 01 F volt at dc 50 and 60 Hz 2kV unbalance LO driven COMMON MODE REJECTION Model 866 Less th...

Page 19: ...Y LIFE CONTINUOUS 350 hours typical with alkaline battery 200 hours typical with carbon zinc battery BATTERY INDICATOR Display indicates LO BAT when less than 10 of life remains DIMENSIONS WEIGHT H 6 30 160 mm x W 2 70 69 mm D 1 20 31 mm Net weight 7 5 oz 210 gm CONSTRUCTION Heavy duty ABS plastic housing OPTIONAL ACCESSORIES Any OMEGA thermistors with 2252 ohms are suitable See the ON series or t...

Page 20: ...quid Crystal Display G4 J1001 1 4 Phone Jack A1 J1002 Battery Clip E1 J1003 Battery Clip F1 Q101 NPN Transistor MPS8099 C2 R101 Resistor 910 kilohms 5 1 4W Composition E2 R102 Resistor 5 4 kilohms 0 1 1 8W Metal Film D4 R102 Jumper R103 Factory selected part of 865 600 B 6 R104 Resistor 4 6 kilohms 0 1 1 8W Metal Film D3 R104 Resistor 10 kilohms 0 1 1 8W Metal Film D3 R105 Resistor 44 kilohms 0 1 ...

Page 21: ... Multiplexer 4053 SEV U102 3 1 2 Digit Low Power A D converter ICL7136CPL F2 U103 Triple 2 Channel Analog Multiplexer 4053 SEV U104 Quad Low Power J FET LF44CN SEV U105 Current Source LM334 E4 VR101 6 2V Zener Diode 1N753 C1 Model 865 Model 866 Figure 6 1 Component Layout ...

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Page 24: ...r otherwise shall not exceed the purchase price of the component upon which liability is based In no event shall OMEGA be liable for consequential incidental or special damages CONDITIONS Equipment sold by OMEGA is not intended to be used nor shall it be used 1 as a Basic Component under 10 CFR 21 NRC used in or with any nuclear installation or activity or 2 in medical applications or used on huma...

Page 25: ...wheel Systems M U Totalizers Batch Controllers pH CONDUCTIVITY M U pH Electrodes Testers Accessories M U Benchtop Laboratory Meters M U Controllers Calibrators Simulators Pumps M U Industrial pH Conductivity Equipment DATA ACQUISITION M U Data Acquisition Engineering Software M U Communications Based Acquisition Systems M U Plug in Cards for Apple IBM Compatibles M U Datalogging Systems M U Record...