TH u ND ER s c IE NTI FI c CORPORATION

Transcription

1 f TH ND ER s c E NT F c CORPORATON. ELECTRONC PSYCHROMETER MODEL 4A - MP RELATVE HUMDTY AND TEMPERATURE MEASUREMENT SYSTEM OPERATNG AND SERVCE MANUAL _J DATE Jne 17, WYOMNG, S.E. ~ : j. ALBUQUERQUE, NEW MEXCO TEL. (505)

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4 TABLE OF CONTENTS \ i ( "..._,,. WARRANTY SPECFCATONS/FEATURES.... GENERAL DESCRPTON... PRE-OPERATONAL NSPECTON. SET-UP/TURN-ON PROCEDURES PROGRAMMNG THE SYSTEM FOR: MANUAL OPERATO~..... HARDCOPY (PRNTER) OUTPUT AUTO MODE OPERATON CHANGNG THE: HARDCOPY TME NTERVAL PRESSURE TME.. DATE.. SWTCHNG TO: 0 c.. o F. SUMMARY OF COMMANDS: DSPLAY FUNCTONS ON/OFF FUNCTONS SET FUNCTONS PROBE ~CK CHANGEOUT NSTRdCTONS FACTORY CERTFCATON SERVCE ' PAGE DRAWNGS L) --\_) M83Cl29 DE83C023 S86D016 S83Al30 S83Bl31 FRONT PANtL DETAL (4A~lMP) PSYCHROMETER PROBE DETAL DRAWNG PSYCHROMETER SCHEMATC DAGRAM DSPLAY BOARD SCHEMATC DAGRAM PROBE AND CABLE WRNG DAGRAM i

5 ; l \._ j WARRANTY Thnder Scientific Corp0ration warrants each instrment of its manfactre to be free from. defect in ma_terials and workmanship. The limit of liability nder this warranty is to repair or replace any part thereof which shall within one year after delivery t0 the original prchaser, and retrned by the original prchaser, prove to be defective after examination by s. This warranty specifically excldes the probe sensors, which may become damaged or broken de to wick changes. is covered by insrance and will be honored if within one week of receipt of the instrment. m.st be athorized by the fact0ry. Shipping damage report is made Warranty retrns ( ) WARNNG -- Calibration seals have been applied to the instrment case, cable, and probe. Shold the instrment and/or associated components be opened or tampered with, or if the seals are broken, Thnder Scientific Corporation accepts no responsibility for calibration and this warranty is void.

6 (j v. i 4A-1MP - MCROPROCESSOR BASErr WET BULB, DRY BULB PSYCHROMETER SPECFCATONS Relative Hmidity (RH) Measrement Range: Garanteed Accracy: Typical Accracy: Temperatre Measrement Range: Garanteed Accracy: Typical Accracy: Readot: Digital Display: Printer nterface: Printer (optional) 1% RH to 100% RH +1% indicated RH +,5% indicated RH 0~100 c / F +.3 C / +.5 F +.1 C / +.2 F 0 c or F (ser selectable),01%rh and.01 Resoltion Trendcom Parallel (std) Centronics Parallel (opt) RS-232C Serial (opt) Trendcom 200 High Speed ntelligent Printer ( ) * FEATURES Z-80 Central Processing Unit, atomatically comptes percent relative hmidity and both temperatre and dewpoint in C and 0 1''. * 3 compter/printer interface options: 2 parallel, 1 serial. * Battery backed-p real time clock. * Timed printer otpt mode allowing ser selectable intervals from 1 minte to 24 hrs in 1 minte increments. * Atomatic Mode capability enables probe aspirator for 1 * * minte prior to each printot. Fll fnction display capability. Not ssceptible to contamination by chemicals or long term exposre to high temperatre and relative hmidity. * Certification of Traceability direct to the National Brea of Standards. 2

7 , ' \.. ) (; GENERAL DESCRPTON The Thnder Scientific Model 4A-l-MP is a microprocessor based Laboratory Standard Psychrometer designed for precise measrement of air temperatre and relative hmidity. The 4A-l-MP ses a 2-blb measrement dry matched pair calibrated Platinm (PRT's) operating nder a controlled referred to as the dry blb, is temperatre. The other PRT, the wet weaved wick (or sock) to facilitate an of distilled water from a reservoir measres a depression temperatre. system employing wet and Resistance Thermometers air velocity. One PRT, sed for sensing air blb, ses a specially nimpeded capillary flow below. The wet blb The signals from the PRT's are converted to digital format, read by the micro~rocessor, linearized, and then converted to actal temperatre data in both degrees c and degrees F. The data is then sed to calclate Percent Relative Hmidity and Dew Point Temperatre. Front panel display of any of the above data is selected by ser inpt at the keyboard. The pper display is the data readot device, and the lower display indicates which data or other fnction is crrently enabled. Upon selection of data otpt to this real-time LED display, crrent readings are pdated 4 to 5 times each second, allowing for fast system response to any changes in the sampled environment. Printer otpt, enabled from the keyboard, allows for hardcopy printots of all crrent psychrometric data. Printer otpt is at ser selectable timed intervals ranging from a 1 minte minimm to a 24 hor maximm, or at any 1 minte increment in between. An Ato Mode featre is also inclded which, when enabled, will pt the probe in synchronos operation with the printer. n this mode, the probe aspirator will atomatically rn prior to any sample for hardcopy otpt. After printot, the aspirator will be disabled and will remain off ntil the next sample time is reached. The Model 4A-l-MP is a precise laboratory instrment and, if handled accordingly, will provide years of excellent service. Q) Q_/ 3

8 ' \ PRE-OPERATONAL NSPECTON The 4A-l-MP Psychrometer is shipped from Thnder Scientific Corp (TSC) calibrated and basically ready for operation. Any damage from shipment shold be reported to TSC within one week of receipt. Prior to each se, the following inspection shold be performed: 1 ) nventory.. enclosed. Ensre all necessary parts and components are 2) nspect the probe for cl~anliness. Pay particlar attention to the wick on the wet blb. f the wick OUT NSTRUCTONS. 3 ) nspect the main psychrometer nit. Ensre the system is clean, that all screws and connetting hardware are tightened, and that all k~ys operate smoothly withot binding or sticking. 4) nspect cables for wear. nicks, cts, or frays, easily withot binding. Cables shold be free from any and all connectors shold mate reqires changing see the section titled PROBE WCK CHANGE -,/.- v ( \ 4

9 SYSTEM SET-UP/TURN-ON PROCEDURES 1) Remove the black probe hosing from its styrofoam holder in the display panel. This hosing contains the Platinm Resistance Thermometers (PRT's). A clean wick. is installed from the factory on the wet blb sensor. To the rear of the hosing is the aspirator motor which draws air over the PRT's. 2) Remove the knrled filler cap on the bottom of the probe hosing. 3) Fill the reservoir with pre distilled water. (N.ever se tap water as this will contaminate the w,ick.). ( ) \..._;' 4) 5) Replace the filler cap and finger tighten, then gently shake excess water from inside the white probe cylinder. Check for leaks arond the bottom edge of the hosing. Finger tighten the knrled knob as necessary. Place the probe in the environment to be tested and then rote and connect one end of the white 12 foot power/signal cable to the connector on the front of the probe hosing. Connection to the probe shold be smooth, as excessive force cold misalign and damage the connectors. 6) Connect on the smooth. the other end of the cable to the mating connector display panel. Connection here shold also be 7) Connect printer (optional) to the mltipin connector directly above the probe cable. 8) Connect the 6 foot AC power cable to the jack. in the display panel and then to a 120 VAC sorce. 9) Trn on the main power switch. 10) The pper display shold show the time in military format, with a blinking decimal point in the middle (the seconds indicator). 11) The lower display shold show Program 7, the time). P--7 (meaning Display 12) Psh the LED TEST btton and ensre that all segments and all 4 decimal points of each display light p. TURN ON S COMPLETE. 5

10 \.,;; \_j PROGRAMMNG THE SYSTEM FOR MANUAL OPERATON The 4A-l-MP is a. versatile instrment and therefore reqires some inpt from the ser. The ser m~t perform at least the following minimm reqirements to operate in manal mode: * Ensre the 4A-l-MP displays the correct time. * Ensre the 4A-l-MP displays the corr~ct date. * npt the atmospheric pressre at the probe environment. * Trn on the aspirator motor. * Select the desired display~ ie Temp, Dew Point, RH, etc. * Trn off the aspirator when measrements are complete. Detailed descriptions follow: 1) Display the TME with the following key strokes: f the time shown on the pper display is incorrect, follow the procedre on CHANGNG THE TME. \_,, 2) Display the DATE with the following key strokes: f the date shown on the pper display is incorrect, follow the procedre on CHANGNG THE DATE. 3) npt the correct barometric pressre in inches of mercry. For example, a pressre of in Hg wold ~e inpt with the following key strokes: For more detailed information, refer to the section titled CHANGNG THE PRESSURE. 4) Trn on the aspirator with the following key strokes: The motor shold trn on and the left decimal point of the lower display shold light. 6

11 5) Select the desired display otpt with these key strokes: Where X is one of the following: 1 - % RH 2 - Dew Point Temperatre 3 - Air Temperatre 4 - Wet-blb Temperatre 5 - Resistance of Dry-blb in Ohms 6 - Resistance of Wet-blb in Ohms 7 - Time 8 - Date ( ) ( ; \_/ 6 ) Once measrement is complete, trn off aspirator with: Take additional measrements by repeating steps 4 thr 6. MPORTANT NOTE The fan monted in the probe hosing is designed with a maximm operating life of 300 hors. The motor need not be rn for more than 10 mintes before taking Temperatre, Dew Point, or Relative Hmidity Measrements. v ' 7

12 ( ' -,, / PROGRAMMNG THE SYSTEM FOR HARDCOPY OUTPUT f a printer is connected to the 4A-l-MP via the mltipin connector on the display panel, hardcopy otpts of all pertinent psychrometric data are availabl~. The following seqences are sed to control the printer otpt. nformation is sent to the printer once each minte nless the ser changes the time interval (see CHANGNG THE HARDCOPY TME NTERVALS). * Trn on the printer fnction with the following kaystro~es: The second decimal point from the left on the lower display shold light. * Trn off the printer fnction with the following keystrokes:,' \ ) i._! The second decimal point shold go ot. When sing the printer, the aspirator shold also be trned on. To enable and/or disable the aspirator, refer to the previos section on PROGRAMMNG THE SYSTEM FOR MANUAL OPERATON. Any one of the following printer/compter interfaces are available: 1) Trendcom compatible parallel 2) Centronics compatible parallel 3) RS~232C serial, 300 to 9600 Bad Conslt TSC for yor particlar reqirements. 8

13 { \ \,_,) PROGRAMMNG THE SYSTEM FOR 'AUTO MODE' OPERATON n 'Ato Mode' operation, the aspirator motor fnction is atomatic and is nder compter control. f the hardcopy otpt is enabled, (as previosly described), the compter will trn on the aspirator precisely 60 seconds prior to print time, and will trn the motor off immediately after print. This featre extends the service of the aspirator motor which has a 300 hor maximm rn-life. t also provides for accracy and repeatability of measrements, as the motor is rn for eqal amonts of time prior ta each and every printot. * To enable the Ato Mode, type the following keystrokes: ( ) Now anytime the printer is enabled, (see PROGRAMMNG THE SYSTEM FOR HARDCOPY OUTPUT), the probe will atomatically trn on and off at the correct times. * Disable the Ato Mode fnction with the following k.ey strokes: The Ato Mode is now disabled and control of the aspirator is solely nder ser keyboard control. The printer fnction is not affected. Note - Defalt interval is 1 minte between printots. This means that in the Ato Mode, when the printer fnction is enabled, the motor will stay on continosly nless the time interval is changed tsee CHANGNG HARDCOPY TME NTERVALS). Note - f the motor happens to be on when either the Ato Mode o-r--the printer fnction is trned off from the keyboard by the ser~ the aspirator motor may also need to be trned off in the same manner. 9'

14 i \.. //. \ \._) CHANGNG THE HARDCOPY TME NTERVAL The 4A-l-MP is capable of sendin.g data to a printer or some other device, sch as a compter, at specified time intervals. The information sent consists of Date, Time, Dry Blb, Wet Blb, and Dewpoint temperatres, Relative Hmidity, and satration Vapor Pressre over water at the Dry and Wet Blb temperatres. A header is sent before the first line of data and every 23 lines thereafter. The time between each printot defalts to the minimm interval of 1 minte each time the system is trned on, bt is keyboard selectable p to 24 hors. * To change the NTERVAL, follow the sample below. This example changes the interval to 1 hor 25 mintes (bt yo can se yor own interval instead). ( \ J (_./ Note that the nmber on the lower display begins flashing when the SET key is pshed. When the EN'l'ER key is pshed, the nmber stops flashing, indicating that the compter acknow,ledges the key and is now awaiting the interval inpt. The interval nmbers will appear on the pper display, shifting the old nmbers ot to the left as the new nmbers are pnched in. (This same procedre occrs for all SET commands; ie, Pressre, Time, and Date.) 10

15 l l \._/ CHANGNG THE PRESSURE The 4A-l-MP has been programmed from the factory with a barometric pressre of inches of mercry (in HG). The instrment ses the barometric pressre for all calclations of Relative Hmidity and D.ewpoint temperatre. rt. is recommended that the absolte pressre be measred in the environment where the probe is to be set p and sed. The pressre shold also be measred freqently dring the operation of the system, as the accracy of the calclations can differ as mch as 2%RH for every inch of mercry. To change the PRESSURE, follow the sample below. example changes the pressre to in HG. This \, ) Yo mst type in all 4 For an explanation of dring this k~yboard HARDCOPY TME NTERVAL. digits inclding the decimal point. the pper and lower display readings seqence, refer to CHANGNG THE..._,,.. \ i 1 1

16 \_) CHANGNG THE TME/DATE The 4A-l-MP contains a battery backed-p Real Time Clock. The clock operates on a for year calendar, meaning that it makes no adjstment for leap year. Shold it reqire setting for any reason, refer to the below procedres. * To change the TME, follow the sample below. This ekample bhanges the time to 3:40 PM. ( ) L; * Note that the time is inpt in MLTARY FORMAT, and that no decimal point is needed between the hors and mintes. Far an explanation of the display readings dring this keyboard seqence, refer to CHANGNG THE HARDCOPY TME NTERVAL. To change the DATE, follow the sample below. change the date to Jne 4th. This wold Note that Jne was inpt as '06' and that the day was inpt as '04'. Both digits of each mst be typed. 12

17 SWTCHNG TO C/~F The 4A-l-MP is capable of both C and F operation. The ser may at any time select which mode to se. When switched, all temperatre displays, in6lding hardcopy otpt, will be affected. Th temperatre data sent to the hardcopy device will be followed by C or F as applicable. * To switch to C, type the following ~eystrokes: * To switch to 0 'F 1 type these keystrokes: NOTE - The pow.er p defalt mode is F. 13

18 SUMMARY OF DSPLAY COMMANDS ( ) [8J8~B ssrn6 B8GJ6 [8]8~~ s:s~.[i] BBm~ 88~ ~ B88B % Relative Hmidity Dewpoint Temperatre Dry Blb Temperatre Wet Blb Temperatre Dry Blb Resistance in Ohms Wet Blb Resistance in Ohms Time Da. te 14

19 SUMMARY OF ON/OFF COMMANDS ( ) BB~~ BB~.~ BB~~ 88,[[][i] 88[;][i] sram~ BB.[[]~ srbm~ Enable Ato Mode Disable Ata Mo<le Trn Probe ON Manally Trn Probe OFF Manally Enable Printer Otpt Disable Printer Otpt switch to 0 c Switch to F / ( 1 15

20 . \_. ) (_) SUMMARY OF SET COMMANDS BBGJBGJGJBGJ6 nterval LGJBLQJBGJGJDGJGJm Pressre 8BGBGJGJBBliJ 1 8BGJBGJDGJGJ[i] Date 'ime ; \ ~ ; v : ;, i ; '.. 16

21 PROBE WCK CHANGEOUT NSTRUCTONS The CK-1 Wick Changeot Kit is provided to easily change wicks in the sensing probe. Wick changes shold be performed after forty hors of operation, or more often, particlarly if the instrment is in a dirty environment. A replacement wic~ spply shold be ordered from Thnder Scientific Corporation in advance of the need and kept on hand. Order PW~lOl Probe Wick $10.00 each Sggested Stock: Minimm Order: F.O.B. 25 $50.00 Albqerqe, New Mexico lf Place probe pside down pon. two blocks of wood or other material, one on each Side of the probe handle. ( v. 2) 3 ) Remove reservoir plg and rbber feet. Gently pry reservoir cover with plastic tool and remove. 4) Careflly remove the for hosing retainer screws located in the corners of the probe; They join the two halves of the probe. 5) Gently remove bottom half of probe hosing, feeding the wick throgh the teflon wick tbe. Keep the teflon a.ir sleeve in place dring removal. NOTE - Blower motor is also loose once hosing is removed. 6,) Lift tef lon air sleeve p and off the sensor rnon ts, taking care to feed the wick throgh the air sleeve avoiding any lateral movement and nde strain pon the sensor. 7) 8) 9) The sensor and wick are now in the open where the wick may be removed. sing the dropper provided, apply several drops of ethyl alcohol to the portion of the wick covering the sensor. Allow to soak for approximately one minte, replenishing the alcohol as evaporation occrs. Using one of the picks provided, gently probe the wick covering the sensor to loosen. Using the crved tweezers provided, very gently psh the wick p on itself or p on the sensor, assisting with the other hand from the reservoir side. (The wick constrction is very similar to a "Chinese finger pzzle" in that pshing tends to release it where plling only l...,

22 \_) tightens the wick and componds the problem of removal). The wi.ck shold expand. When this occrs, se the tweezers to slide the wick from the sensor. MPORTANT! - f wick is frozen to the sensor with deposits de to contaminated water, DO NOT FORCE. This will break the sensor leads, casing expensive repair costs. f alcohol does not loosen the deposit, retrn to Thnder Scientific Corporation for removal. Thnder Scientific is not responsible for lead break.age and/or sensor replacement if sch occrs. f a wick changeot schedle is maintained, this problem will not occr. 10) Apply finger cots spplied to the thmb and index finger of each hand. soak a clean cloth with alcohol and remove all traces of talcm from the oter srfaces. f this is not done, the wick becomes contaminated. 11) The replacement wicks are spplied in a sealed vial of alcohol. Remove wick from the vial. (. ) 12) Using the ble taper tool provided, tool approximately one inch or more, pshing on the wick. 13.) Remove from tool and clip frayed end sqare. psh the wick onto the casing expansion by 14) Slide wick gently onto sensor and over the teflon to the sholder. 15.) Using the dropper, apply several drops of w.ater on the wick at the sensor. Note wick expands slightly, indicating water retention. Gently form the wick arond end of sensor and flatten between the sensor and wick tbe to offer minimm wind resistance. 16) Feed wick thr teflon air sleeve, slide sleeve over teflon 17) Feed sensor monts, and seat it on the probe half. probe cover. wick thr wick tbe in bottom probe half and mate the halves. Coil wick inside reservoir and replace 18) Replace for corner screws, rbber feet, and reservoir plg. 18

23 FACTORY CERTFCATON & RECERTFCATON Factory certification is initially ~rovided with each DBW instrment on a. no-charge basis. Certification is good for one year or longer: However, the instrment shold be recertified by the factory on a re9lar yearly basis. This is done for a calibration charge of $ per temperatre and hmidity point. Generally, three temperatre and hmidity points are sfficient. f the instrment reqires more than genbral cleaning, a reconditioning charge of $ is reqired. NBS CERTFCATON & RECERTFCATON f it is desired that the instrment be certified by the National Brea of Standards (NBS), all NBS charges are passed net to the cstomer, pls F.O.B. charges to and from, pls insrance coverage. ( ) n the case of NBS certification, Thnder Scientific Corporation does reqire that the instrment be shipped direct from Thnder to NBS and retrned prior to shipment to the cstomer. The same is reqired for recertification. The instrment shold be retrned to Thnder Scientific for inspection and reconditioning prior to recertification by the Brea. ******** SUMMARY Yor Thnder Scientific psychrometer is a standard and shold be treated accordingly. will reslt in many years of service. precise Good laboratory maintenance Shold any problems or qestion arise relative to yor instrment, direct all correspondence to the following address: Thnder scientific Corporation 623 Wyoming S.E. Albqerqe, New Mexico Or call collect (505) Q

24 i!. '-) PRNTER/COMPUTER\ NTERFACE OPTONS There ar:-e three compter/printer interfac:e options cr:-r:-ently available for:- the 4A--1-MP Psychr;-orneter:-. Based pon which option' yor;- nit has, the 25 pin otpt connector w.i ll match one of the below 1 isted pinots. DB,...25 Pins , Trend~om Parallel Gr;-ond D1 03 D5 07 Bsy Strobe 00 D2 04 D6 Centronics PClr;-allel Strobe D D D7 Bsy Grond Grond Gi'i'ond Grond Gi'i'ond Grond Gi'i'ond RS-232 Sel'.'i al XMT Data RTS * CTS ** DSR Grond ** DTR No special cables sho 1 ld be reqired. Each, of the otpt options al':'e configred so as to make the proper connections with the peripheral device sing onj.y a flat ribbon cable and the appropdate inslation displacement connectors. ( ie DB-25, 36 pin Centr:-onks, 20 pin Dal Row DC, etc. ) nterface cables ar:-e available frorn Thnder Scientific Corporation. Serial option notes: ( * DB-25 pins 4 and 5 ar:-e tied together inside the 4A"-1-MP~ ** DB-25 pins 6 and 20. are tied together inside the 4A-1-MP. Either of these 1 ines rnay be sed: as a BUSY/READY handshake. lir1e. f handshaking' is sed, the receiving device sho:ld be able to accept one more fill character in addition to the one ct..trrentlybeingsent de to the da.ble-bffered natre of the UART sed within: the 4A'-1-MP. Signals g!'l'eater than +5 volts = READY Signals greater than -5 volts = BUSY lf pins 6 and 20 are leflt r;iterminated, READY is assrned.

25 - -- f (1) ' ' OJ,._ J co an V "",\ ~ E = C\J ( ) J

26 c--, RESERVOR (REMOVABLE COVER FOR ACCESS) - THREADED NSERT.5DO" DEEP 1/4-20 SCREW (4 PLCS. RUBBER FEET (4 PLCS. PRT ELEMENT (ORY BULB! PRT ELEMENT (WET BULB) l!~!j FRONT VEW >z ARFLOW. y.,,, ==. ''. > '< ~ _,,. ~rl SDE VEW FAN "'... : l-""""" \._l. BOTTOM VEW KNURLED KNOB (REMOVABLE ARFLOW THUNDER SCENTFC CORP 61] WYOMNG S.. AUUQUUQU. NW '41 CO 171'Jl fo:r"..;[j _ "." v O"' psychrometell -- ::~'.: MODEL 4A-MP 11:!n-eon ~11 11r NA DE83G023

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30 c_= c c_:_ REVSON.;;.S LTR DESCRPTON --DAf( - APPROVtD l L f ~- a , b c d U Q Q 26 l' ll , ,;._ l L2 NOTES:- : -, s AN LED DRVER SYSTEM THUNDER SClENTlFC CORP. - Ul WYOMNG., AllUOUllO!J, NW MllllCO L 1 ANO L2 ARE LED DSPLA. vs: tolc1u.-t1cc- UHUll J1 S A 14-PN CONNECTOR, SHOlJU) COf\l\ECT, OTHUWll[ ll'lcplld 4A... 1-MP faactoh DCC AHOLU :: :: :: WTH J3 OF tv'0tl-er BOARD BY~ NEW 4. Pro A.1 tv'f CAfl. BETWEEN PN 9 & 19 Of=U1,... CtUCRlO Al'PAOVALS DATE DR.AW'D A V.Zi DSPLAY SCHEMATC SCAl[ -r\ja DRAs'a3 A 130 f\.- \MO~ -C-lllA.~MiC1 HC: tollo. lito )0\ oo Nor sca 011Aw11m tm 1 or 1

31 C~,,.-- C. (_ LTR REVSONS -Cl(SCR11'110H - OATl- - APP!OvtO WET BULB DRY BULB PROBE 1/2 +26V RETUR +26V A' ~ Di. ~ B' ~ - 4-< ~. CABLE 112 < ( A 1 A'. ~ o,_( (B 1 Bl (. r,.f 1 F "::: < '. l -(E' Et (, - - MANFRAME - A ~. _ <~ : (61. -! <F1. j ( E!::.a1-.,...-=- -. fmctk>h Of..C ;: ;: ;: AF'PAOVAlS OAAW"t:>R.h -THUNDER SCENTFC CORP 6ll WYOMNG S,l, 'AllUOUUOU, HM MXCO 1711l CHtC LD SCAlC- - MODEL 4A+ MP SCEMEMATC PROBE CONNECTOR -'8 DRAWHGSB3Bl31 fn'\ 11~-" " ~11...,.,.. C llritc. "rlll ALO OU JO, 111>\J - DO NOT SCALE OR-AWNG - - SHCCT

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