Fluke 1502A manuale d’uso

1502A Thermometer Readout User’ s Guide Rev. 722101 ENG Hart Scientific[...]

Limited W arranty & Limitation of Liability Each product from Fluke Corporation, Hart Scientific Di vision ("Hart") is warranted to be free from de - fects in material and workmanship under normal use and s ervice. The warranty period is three years for the Thermometer Readout. The warranty period begins on the date of the shipment. P[...]

T able of Contents 1 Bef or e Y ou Start . . . . . . . . . . . . . . . . . . . . . . . . . . 1 1.1 Symbols Used . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 1.2 Safety Information . . . . . . . . . . . . . . . . . . . . . . . . . . 2 1.2.1 W arnings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 1.2.2 Cauti[...]

7 Digital Communications Interface . . . . . . . . . . . . . . . 23 7.1 Serial Interface . . . . . . . . . . . . . . . . . . . . . . . . . . . 23 7.1.1 Setting the Baud Rate . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23 7.1.2 Automatic T ransmission of Measurements . . . . . . . . . . . . . . . . . . . 24 7.1.3 T ime Stamp and Syst[...]

iii Figures Figure 1 Connecting a four-wire probe . . . . . . . . . . . . . . . . . . . . . . 12 Figure 2 1502A Front Panel . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13 Figure 3 1502A Back Panel . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14 Figure 4 Parameter Menu Structure . . . . . . . . . . . . . . . . . . . . . . . . [...]

iv T ables T able1 International Electrical Symbols . . . . . . . . . . . . . . . . . . . . . 1 T able 2 Matching Certif icate V alues to 1502A ITS-90 Coefficients . . . . . . . 18 T able 3 Setting Coef f icients Rtpw , a8, b8, a4, and b4 . . . . . . . . . . . . . . 19 T able 4 Setting Coef f icients Rtpw , a5, and b5 . . . . . . . . . . . . . . . [...]

1 Bef ore Y ou Start 1.1 Symbols Used T able 1 lists the symbol s that may be used on the i nstrument or in this manual and the meaning of each symbol. Symbol Description AC ( Alternating Current) AC- D C Batter y Complies with European Uni on Directiv es DC (Direct Current ) Double Insulated Electric Shock Fuse PE Ground Hot Surf ace (Bur n Hazard[...]

Symbol Description On Canadian Standards Associati on O VERV OL T AGE (Installat ion) CA TEGORY II , P ollution Degree 2 per IEC1010-1 r e - f ers to the le vel of Impulse Wit hstand V oltage protection provided. Equipment of O VERV OL T AGE CA TEGOR Y II is energy-consuming equipment to be suppl ied from the fix ed install ation. Examples include [...]

Before initial use, or after transport, or after s torage in humid or semi-hu mid en vironments, or anytime the instrument has not been ener gized for more than 10 days, the instrument needs to be energized for a "dry-out" period of 2 hours before it can be assumed to meet all of the safety requirements of the IEC 1010-1. If the product i[...]

Keep the probe wires clean and aw ay from fluids. 1.3 A uthoriz ed Service Centers Please contact one of the follo wing authorized Service Centers to coordinate service on your Hart product: Fluke Corporation, Hart Scientific Di vision 799 E. Utah V alle y Driv e American Fork, UT 84003-9775 USA Phone: +1.801.763.1600 T elefax: +1.801.763.1010 E-ma[...]

Fluke South East Asia Pte Ltd. Fluke ASEAN Regional Of fice Service Center 60 Alexandra T errace #03-16 The Comtech (Lobby D) 118502 SINGAPORE Phone: +65 6799-5588 T elefax: +65 6799-5588 E-mail: antng@singa.fluke.com When contacting these Service Cente rs for support, please hav e the following information av ailable: • Model Number • Serial N[...]

2 Intr oduction The 1502A is a low-cost high-accurac y dig ital thermometer readout designed to be used with 25 Ω and 100 Ω R TDs an d SPR Ts. Its unique co mbination of fea - tures makes it suitable for a wide variety of applicatio ns from laborator y mea - surement to industrial processes. Features of the 1502A include: • Measures 25 Ω and 1[...]

3 Specifications and En vir onmental Conditions 3.1 Specifications Resistance Range 0 Ω to 400 Ω , auto-ranging Resistance Accuracy, one year 1 0 Ω to 20 Ω : 0.0005 Ω 20 Ω to 400 Ω : 0.0025% (25 ppm) of reading Resistance Accuracy, short term 1, 2 0 Ω to 30 Ω : 0.0005 Ω 30 Ω to 400 Ω : 0.0015% (15 ppm) of reading Temperature Range 3 –[...]

Weight 2.2 lb. (1. 0 kg) Safety OVERVOLTAGE (Installation) CATEGORY II, Pollut ion Degree 2 per IEC 1010-1 1 Accuracy specificati ons apply within the r ecommended operating temper ature range. Accuracy l imits are increased by a factor of the temperature coefficient out side this range. 2 Short-term accuracy in cludes nonlinearity and noise uncert[...]

4 Quic k Start This section briefly explains the basics of setting up and operating your 1502A thermometer readout. 4.1 Unpac king Unpack the thermometer carefully and i nspect it for any damage that may ha ve occurred during shipment. If there i s shipping damage, notify t he carrier immediately . V erify that the follo wing components are present[...]

to pins 4 and 5. (Pins 1 and 5 source current and pins 2 and 4 sense the poten - tial.) If a shie ld wire is present it should be connected to pi n 3. A two-wire probe can al so be used with the 1502A. It i s connected by attaching one wire to both pi ns 1 and 2 of the plug and the other wire to both pins 4 and 5. If a shield wire is present it sho[...]

5 P ar ts and Controls 5.1 Fr ont P anel Buttons See Figure 2. The front panel buttons are used to select units of measurement, access operat - ing parameters, and alter operating parameters. The function of each button is as follows: C/Probe —This button selects units of degrees Celsius. In conjun ction with the Menu button, it selects the probe[...]

5.2 Rear P anel See Figure 3 . Serial Port - The DB-9 connector i s for interfaci ng the thermometer to a com - puter or terminal with serial RS-232 communications. Probe Connector - At the rear of the thermometer is t he probe connector . The probe must be connected for operation. Po wer Switch - The po wer switch is l ocated on the rear of the th[...]

6 General Operation This section e xplains basic operation of the 1502A Thermometer . 6.1 Selecting Units T emperature can be displayed in degrees Celsius (indicated with “ C ”), degrees Fahrenheit (indicated with “ F ”), or Kelvin (indicated with “ A ” for absolute). The resistance of the sensor can al so be displayed (indicated wi th [...]

1502A Thermometer Readout User’s Guide 16 Menu Sample Comm (Cal) Probe Set clock Set filter Set probe type Enter password Set time stamp Set current Set coefficients Set menu lockout Set baud rate Set power saver Set CAL0 Set sample period T est conversion Set CAL 100 Set duplex Set CAL 400 Set linefeed Factory reset Set GPIB address Set GPIB EOS[...]

when all the digits are correct. If the pa ssw ord is entered correctly the f irst pa - rameter in the menu will appear . 6.4 Selecting the Probe Characterization Before the 1502A can measure temperature accurately it must know ho w to cal - culate temperature from the resistance of the sensor . Y ou must select a con ver - sion type and enter the [...]

digit will flash. Use the U and D b uttons to change a d igit. Once th e sign and digits are correct, press Enter to accept the number . If you decide to cancel any changes you hav e made, you may do so by pressing the Ω / Exit button. This will immediately skip to the ne xt coef fi cient. If the coef ficient also requires an expone nt, it will ap[...]

Example 1: A PR T was calibrated to ITS-90 and its calibration certificate states v alues for coeff icients Rtpw , a4, b4, a8, and b8. Set the 1502A parameters wi th v alues from the certificate as follows. Example 2: A PR T was calibrated to ITS-90 and its calibration certificate states v alues for coeff icients Rtpw , a5 and b5. Set the 1502A par[...]

Example 3: A PR T was calibrated to ITS-90 and its calibration certificate states v alues for coeff icients R(273.16K), a6, b6, c6, and d. Set the 1502A parameters wit h val - ues from the certificate as follows: 6.4.4 Callendar -V an Dusen (R TD) Con version The R TD con version uses the Callendar -V an Dusen equation: [] () rt C Rt tt t Rt °= +?[...]

6.4.5 IPTS-68 Con version The IPTS-68 characterization con verts r esistance to temperature according to the International Practical T emperature Scale of 1968. The applicable coef fi - cients are R 0 (“ r0 ”), α (“ ALPHA ”), δ (“ dELtA ”), a 4 (“ A4 ”), and c 4 (“ C4 ”). Y o u can also select the temperature scale (“ SCALE [...]

Compare this temperature with th e temperatures listed on the p robe calibration report to verify t hat the coef f icients you entered are correct. 6.5 Filtering While measuring temperature, the readings may appear to v ary . This may be due to actual v ariations in temperature or elect rical noise internal to the 1502A. The filter helps to smooth [...]

7 Digital Comm unications Interface Remote communications allows an e x ternal de vice, such as a computer , to com - municate with the 1502A to obtain measurement data and cont rol its operati on. Communication is accomplished with v arious commands issued to the 1502A through the RS-232 port or optional IEEE-488 port. A full list of commands is g[...]

7.1.2 A utomatic T ransmission of Measurements The 1502A can be programmed to automati cally send measurements to a re - mote printer or termin al. The transmission interval is set using the “ SA PEr ” sample period parameter . This is set in the Comm menu after the baud rate pa - rameter . The disp lay will briefly indicate “ SA PEr ” and [...]

to the time stamp parameter . The display will br iefly show “ ti Sta ” then the time stamp state which is either O N or OFF . Use the U and D buttons to change the state and p ress Enter . ON enables transmission o f the time stamp and OFF disables it. The time stamp can also be set using the “ST” communications command. The command ST=ON&[...]

7.2.1 Setting the Ad dress The IEEE-488 bus requires that each de vi ce has a unique address. The default address of the 1502A is 22 b ut can be changed if necessary . The IEEE-488 ad - dress of the 1502A is set within the Comm menu after t he serial linefeed pa - rameter . (This menu option will not appear if the IEEE-488 interface is not installe[...]

27 7 Digital Communications Interface Remote Commands Command Description Measurement Commands T read measurement (includes label, unit , and time) F[ETCH?] r ead measurement value (SCPI compatible) SA[=[[[hh:] mm:]ss] read [or set] serial sample period U=C|F|K|O select units ST[=ON/OF] read [or set] t he time stamp CL[=hh:mm:ss] read [or set] the [...]

7.3.1.1 Reading T emperature The most recent temperature measurement can be read using the following command: T<EOS> reads the most recent measurement The syntax of the response is as follo ws: t:_nnnn.nnn_u or t:_nnnn.nnn_u_hh:mm:ss The _’ s represent space characters. The n ’ s represent the digit s of the measure - ment value. If fe we[...]

7.3.1.2 A utomatically T ransmitting Measurements By setting the sample period, the 1502A can be programmed to automatically transmit measurements from the RS-232 por t at specif ied intervals. The sample period can be set remotely using t he commands: SA=[[hh:]mm:]ss<EOS> sets the sample period SA=0<EOS> disables automatic transmission[...]

7.3.2.1 Selecting the Characterization The follo wing commands can be used to se lect the probe characterization and coeff icients: P=90<EOS> selects the ITS-90 characterization P=68<EOS> selects the IPTS-68 characterization P=R<EOS> or P=S<EOS> selects the standard Callendar-V an Dusen characterization R0=<value><E[...]

7.3.3.1 Setting the Filter The filter helps to reduce variations in the measuremen ts. The filter can be set remotely using the command: FI=<value><EOS> sets the f ilter time constant FI=0<EOS> disables the filter The value is the f ilter time constant in seconds. It must be between 0 and 60 in - clusiv e. A value of 0 disables th[...]

LF=OF<EOS> disables linefeed 7.3.5 Calibration Commands The following commands are used in calibrating the instrument. 7.3.5.1 Entering the P ass wor d In order to set the calibration parameters the passw ord must be issued f irst. The following command enables access t o the calibration parameters: *P A=2051<EOS> enables the calibratio[...]

ver. mmmmm,v .vv The m ’ s represent digits of the model number . The v ’ s represent the digit s of the firmw are versi on number . As an example, if the version number was 1.10 the response would be “v er .1502A,1.10". The following IEEE-488.2 a nd SCPI co mpatible command can be used to read the manufacturer , model number , serial nu[...]

8 Calibration Pr ocedure The 1502A uses a three-point calibration scheme with a quadrati c polynomial correction function to maintain the accura c y of its resistance measurement. The three calibration poin ts are at 0 Ω , 100 Ω , and 400 Ω . Three calibration pa - rameters determine the correction function: CAL0, CAL100, and CAL400. The CAL0 pa[...]

power . The *C0=<value><EOS>, *C1=<value> <EOS>, and *C4=<v alue><EOS> commands can be used to set the val ues of the CAL0, CAL100, and CAL400 parameters respecti vely . 8.2 Calibration Procedure Calibrati on requires four-wire 100 Ω and 400 Ω resist ors of 6.25 ppm uncer - tainty and a 0 Ω resistor (or short)[...]

9 Maintenance • The calibration instrument has been designed with the utmost care. Ease of operation and simplicity of maintenance have been a central theme in the product development. Therefore, with proper care the instrument should require very little maintenance. A void operating the instrument in an oily , wet, dirty , or dusty environments.[...]

10 T r oubleshooting In case you run into dif ficulty while operat ing the 1502A, this section provi des some suggestions that may help you solve the probl em. Belo w are se veral sit ua - tions that may arise follo wed by possible causes of the problem and suggested actions you might take . Incorrect T emperature Reading While attempting to measur[...]

• Stem conduction error . The problem may be that the actual temperature of the sensor is not what you expect. This is often the result of stem con - duction where heat flowing through the stem of the probe to ambient af - fects the temperature of the probe. It is very important that immersion probes be inserted to an adequately depth into the ma[...]

10.1.1.1 Imm unity T esting The instrument was t ested to the requirements for industria l locations. This al - lo ws the instrument t o be used in all types of locations from the l aboratory to the factory floor . Criterion C was used fo r Electrostatic Dischar ge (ESD, IEC 61000-4-2) and Electric F ast T ransit (EFT , Burst, IEC 61000-4-4). If th[...]