Page 1
Diatek® Model 600 Thermometer
Thermo Menu
Operation Manual
Technical Manual
Page 2
© 1996 by Diatek Instruments, Inc., A Welch Allyn Company. All rights reserved. No part of this manual may be reproduced
or transmitted in any form or by any means, electronic or mechanical, including photocopy, without prior consent in writing
from Diatek. Printed in the U.S.A.
Diatek is a trademark of Diatek Instruments, Inc. All rights reserved.
Model 600
Page 3
Technical Manual
TABLE OF CONTENTS
WARRANTY.............................................................................................................................3
MODEL 600 OPERATIONAL CHARACTERISTICS................................................................4
Normal Mode.........................................................................................................................4
Monitor Mode.........................................................................................................................4
Pulse Timer............................................................................................................................4
Backlight................................................................................................................................4
Error Indicators......................................................................................................................5
Broken Probe .................................................................................................................................5
Low Battery ....................................................................................................................................5
Instrument Malfunction...................................................................................................................5
Self-Tests...............................................................................................................................5
Battery Installation Display Test.............................................................................................5
Thermometer Startup Tests...................................................................................................5
Display and Horn Test....................................................................................................................5
Internal Calibration Test .................................................................................................................5
Internal Microprocessor Test..........................................................................................................6
Battery Life.............................................................................................................................6
Shelf Life........................................................................................................................................6
Temperature Taking Without Backlight...........................................................................................6
Temperature Taking With Backlight ...............................................................................................6
C/F Mode Switch....................................................................................................................6
Normal/Monitor Mode Switch.................................................................................................6
MODEL 600 THEORY OF OPERATION..................................................................................7
Technical Overview................................................................................................................7
Temperature Measurement and Display................................................................................7
Probe Temperature Measurement.........................................................................................8
Monitor Mode Operation........................................................................................................8
Normal Mode Operation ........................................................................................................8
SELF TESTS.........................................................................................................................9
Internal Calibration Test .................................................................................................................9
Internal Microprocessor Memory Test.............................................................................................9
Broken Probe Test .........................................................................................................................9
DISPLAY................................................................................................................................9
Display Voltage Reference.............................................................................................................9
Display............................................................................................................................................9
Horn ...............................................................................................................................................9
Backlight.........................................................................................................................................9
Power Consumption ............................................................................................................10
Low Battery Detection..........................................................................................................10
Pulse Timer Operation.........................................................................................................10
SPECIFICATIONS..................................................................................................................18
Model 600 1
Page 4
Diatek, A Welch Allyn Company
OPERATING INSTRUCTIONS...............................................................................................19
Set-up Procedure.................................................................................................................19
Preparation for temperature measurement:.........................................................................19
Normal Mode Operation ......................................................................................................19
Oral Temperature Measurement ..................................................................................................19
Rectal Temperature Measurement...............................................................................................20
Monitor Mode Operation......................................................................................................20
Backlight Operation .............................................................................................................20
Pulse Timer..........................................................................................................................20
°F/°C Conversion.................................................................................................................20
Error Indicators....................................................................................................................21
Broken Probe ...............................................................................................................................21
Low Batteries................................................................................................................................21
Probe Position Error.....................................................................................................................21
Malfunction...................................................................................................................................21
Self Tests.............................................................................................................................21
Initial Power Up Display................................................................................................................21
Calibration Check.........................................................................................................................21
Microprocessor Self Check...........................................................................................................22
Cleaning and Sterilization....................................................................................................22
Battery Replacement...........................................................................................................22
Calibration Key Procedure...................................................................................................22
Test Procedure.............................................................................................................................23
M9600 Procedure................................................................................................................24
MODEL 600 TROUBLESHOOTING.......................................................................................24
PARTS LIST (units with serial numbers equal to or greater than 193309) ......................26
PARTS LIST (units with serial numbers less than 193309)...............................................27
RECOMMENDED SPARE PARTS FOR MODEL 600 ...........................................................28
MODEL 600 PREVENTATIVE MAINTENANCE ....................................................................29
TABLE OF FIGURES
Figure 1 - Block Diagram........................................................................................................11
Figure 2 - Schematic...............................................................................................................12
Figure 3 - Schematic (earlier serial numbers).........................................................................13
Figure 4 - Printed Circuit Board Component Layout...............................................................14
Figure 5 - Final Assembly.......................................................................................................15
Figure 6 - Operating Controls and Components.....................................................................17
2 Model 600
Page 5
Technical Manual
W ARRANTY
1-YEAR LIMITED WARRANTY ON NEW INSTRUMENTS
Diatek Instruments, Inc. (Diatek) is warranted to be free from original defects in material and
workmanship under normal use and service for a period of one year from the date of first shipment
from Diatek. This warranty shall be fulfilled by Diatek or its authorized representative repairing or
replacing at Diatek's discretion, any such defect, free of charge for parts and labor.
Diatek should be notified via telephone of any defective product and the item should be immediately
returned, securely packaged and postag e prepaid to Diatek. Loss or dam age in shipment shall be at
purchaser's risk.
Diatek will not be responsible for loss associated with t he use of any Diatek product that (1) has had
the serial number defaced, (2) has been repaired by anyone other than an authorized Diatek Service
Representative, (3) has been altered, or (4) has been used in a manner other than in accordance with
instructions.
The information in this manual has been car efully reviewed and is believed to be accurate; however, no
responsibility is assumed for inaccuracies. Furthermore, this information does not convey to the
purchaser of Welch Allyn or Diatek devices any license under the patent rights to the manufacturer.
: Instrumentation purchased new from
Model 600 3
Page 6
Diatek, A Welch Allyn Company
MODEL 600 OPERATIONAL CHARACTERISTICS
The Diatek Model 600 Digital Thermometer is a portable instrument for measuring patient
temperatures over the 84°F to 108°F (28.9°C to 42.2°C) range. The Model 600 features an LCD
readout with backlight, interchangeable probes, disposable prove covers, disposable batteries with a
capacity for up to 45,000 temperatures, automatic power shutdown, both normal and monitor modes of
operation and self-calibration/test capability.
Normal Mode
Removal of the probe automatically turns on the Model 600 and places it in the predict mode when
selected by the normal/monitor slide switch. All segments of the display except the pulse timer are
lighted simultaneously for 6 seconds as a display test and the horn is tested for 0.1 seconds. The
display will read 84.0 (28.9) with the down arrow on until the probe exceeds that temperature and will
ten display a rising temperature for about 30 seconds.
When the readout has stabilized, the horn will sound for 1 second, the “F” or “C” symbol will light and
the display will remain fixed indicating the end of the temperature taking cycle. The displayed
temperature will be the actual probe temperature plus a computed correction factor. The probe
temperature is sensed about 4 seconds from turn on to correct for ambient probe temperature
variations. If the temperature measurement cycle is not completed within 5 minutes from turn on, the
thermometer will turn off at that time. A temperature in excess of 108°F (42.2°C) will cause an error
condition to be indicated by the horn beeping twice every 10 seconds and the up arrow blinking. Five
minutes of this error condition causes the thermometer to turn off. Returning the probe to its holder
and then removing it will restart the thermometer.
Note: The normal mode display is peak reading and will not read down.
Monitor Mode
Removal of the probe automatically turns on the Model 600 and places it in the monitor mode when
selected by the normal/monitor slide switch. All segments of the display except the pulse timer are
lighted simultaneously for 6 seconds as a display test and the horn is tested for 0.1 seconds. The
display will then indicate the actual probe temperature, updating every 1.5 seconds as long as it
remains within the 84°F to 108°F (28.9°C to 42.2°C) range, and will show the appropriate up or down
arrow when outside this range. Five minutes of operation outside the operating range will cause the
thermometer to turn off.
Pulse Timer
Pressing the pulse timer switch at any time causes the 30 second clock type display to start. One
additional segment is turned on each second until 30 seconds has been reached at which time the
timer display goes blank. The horn sounds for 0.1 second at 0,15, and 30 seconds. Pressing the timer
switch while the timer is running causes the timer to restart. The switch will not respond if pressed
sooner than 1.5 seconds since the last timer activation.
Backlight
The backlight is activated as long as the backlight switch is pressed and the thermometer function is
active. In the predict mode, activating the backlight any time prior to the end of the temperature taking
cycle will cause the backlight to turn on for 5 seconds when the final temperature has been reached
and the horn sounds. No backlight is available when only the pulse timer is in use.
4 Model 600
Page 7
Technical Manual
Error Indicators
Probe Position Error—During normal mode operation the visual probe position error indicator will be
displayed as long as tissue contact is broken and the probe temperature is falling. This display
indicates that a condition exists which may not provide accurate temperatures. The error indicator does
not affect the temperature taking cycle in any way.
No temperatures may be taken when any of the following error conditions exist:
Broken Probe
A probe error will be indicated if the probe circuit is open (below 10° greater than 60,000 ohms) or
shorted (above 150° F or less than 2,000 ohms). The horn sounds a double beep repeating every 10
seconds with the probe error display flashing. The unit will shut off automatically after 5 minutes of
error indication. The error will be detected any time during predict or monitor mode operation.
Low Battery
A low battery condition exists when the battery voltage drops to approximately 3.0 volts. A low battery
indication may occur any time during monitor mode operations but only at the start of a predict mode
temperature. If a low battery condition exists prior to starting the pulse timer, the low battery error will
be displayed when the timer is started and any normal mode temperature in progress will abort at that
time. The low battery error displays a flashing symbol with a double horn beep sounding every 10
seconds. The unit will shut off automatically after five minutes of error indication.
Instrument Malfunction
A malfunction error will be indicated if either the internal calibration self-test or the internal
microprocessor self-test fails. The malfunction indicator flashes with a double horn beep sounding
every 10 seconds. The thermometer will automatically shut off after five minutes of error indication.
Self-Tests
Battery Installation Display Test
Immediately following the installation of batteries into the Model 600, a one time only display test is
provided. All segments of the entire display (including the pulse timer and error indicators) are
sequentially lighted for 0.4 seconds. The entire test takes 25 seconds and must occur prior to starting
any temperature or timer functions.
Thermometer Startup Tests
Display and Horn Test
Each time the probe is removed from its holder all display segments (except for the pulse timer) are
lighted for 6 seconds as a visual display test. During the display test the horn sounds for 0.1 second.
Internal Calibration Test
During each thermometer startup display test a precision resistor is used to check the thermometer
calibration at 100.5°F (38.1°C). A failure of the thermometer to measure the calibration resistor within
±0.2°F will cause the malfunction error to flash, the horn will sound with a double beep every 10
Model 600 5
Page 8
Diatek, A Welch Allyn Company
seconds and no temperature measurement will be allowed. The thermometer will automatically shut off
after 5 minutes of the error display.
Internal Microprocessor Test
During each thermometer display test a check sum of all program memory is calculated and compared
against a reference stored in the program memory. An error in the check sum will cause the
malfunction error to flash, the horn will sound with a double beep every 10 seconds, and no
temperature measurement will be allowed. The thermometer will shut off after 5 minutes of the error
display.
Battery Life
Shelf Life
The shelf life of
70°F. The storage life degrades rapidly with increased temperature.
carbon zinc chloride
or
alkaline
batteries should be at least three years when stored at
Temperature Taking Without Backlight
The Model 600 should operate continuously for about 2,000 hours when the backlight is not used. If an
operating time of 2 minutes per temperature is assumed then the potential number of temperatures
that can be taken should be about 2,000 hours @ 30 temperatures/hour = 60,000 temperatures.
Temperature Taking With Backlight
The backlight uses about 20 times more power than the rest of the thermometer. If 20 seconds of
backlight usage is assumed for each temperature taken then the number of temperatures that can be
taken should be about 17,300 temperatures.
C/F Mode Switch
The display mode may be changed between Fahrenheit and Celsius at any time prior to, during, or
after taking a temperature by activating the C/F slide switch. The numbers will change as the switch is
activated, however, the C/F indicator is only visible at the end of a normal mode temperature.
Normal/Monitor Mode Switch
The selection of normal or monitor mode operation should be made prior to turning on the thermometer
by setting the normal monitor switch to the desired position. Once the thermometer has been turned
on, a change from normal to monitor mode may be made at any time, however, a change from monitor
to normal will cause the horn to beep twice and the thermometer to shut off. This error indication and
shut off prevents a normal mode temperature from being started with the probe already in place.
6 Model 600
Page 9
Technical Manual
MODEL 600 THEORY OF OPERATION
Note: Refer to Model 600 Thermometer Block Diagram and Model 600 Schematic Diagram.
Technical Overview
The heart of the Model 600 is comprised of two custom integrated circuits which provide the
microprocessor and analog circuit functions. All control and display functions are governed by the
microprocessor (U2) and all analog interfacing to the microprocessor, probe, horn and backlight is
provided by U1. Probe resistance measurements are made by ratioing pulse widths generated by
sequentially switching in two calibration resistors and the probe thermistor. These pulse widths are
measured by the microprocessor which calculates the probe resistance. The actual probe temperature
is then calculated from the probe resistance.
During monitor mode operation, the actual probe temperature appears directly on the liquid crystal
display which is driven by the integral LCD driver on the microprocessor.
During normal mode operation, the shape of the rising temperature curve is monitored and a
continuously computed correction factor is added to the actual probe temperature. The normal mode
temperature cycle is terminated when the predicted temperature remains stable.
All switch inputs are monitored by the microprocessor which in turn activates the required functions.
Inputs to the microprocessor are A/D output pulse widths, switches, low battery detection, power on
reset, microprocessor clock and interval timer clock.
Outputs from the microprocessor control the display, analog IC and display power, backlight, horn and
calibration resistor selection.
To extend battery life, the power to both the analog lC (U1) and the LCD reference are turned off and
the microprocessor is put to sleep when possible.
Power to the thermometer is always connected and is not turned on and off by the probe or pulse
switch functions.
Temperature Measurement and Display
When batteries are installed in the thermometer, C4 and RN1-B provide a power on reset pulse to the
microprocessor (U2-56). C3 and RN1-A set the microprocessor clock frequency at approximately 200
kHz. Following the high going reset pulse, the microprocessor initiates the power on display test which
causes display segments (DS1 ) to be sequentially lighted for 0.4 seconds and then extinguished. After
the completion of the display test which lasts approximately 25 seconds, the microprocessor then goes
into a sleep mode awaking 8 times per second to test the probe switch S1. If the probe is in the
thermometer (S1 open) or the probe is disconnected, then the microprocessor returns to sleep for
another 1/8 of a second. The pulse timer switch (S5) is connected to an interrupt input on the
microprocessor (U2-63) and will wake up the microprocessor and start the 30 second pulse timer.
In the sleep mode and even when only the pulse timer is active, the 200 kHz clock (U2-59) will be seen
to turn on for about 2 milliseconds every 1/8 of a second. If when tested, the probe switch circuit is
found to be active, the microprocessor turns on display power by setting U2-10 low and initiates a 6
second display test which turns on all display segments except the 30 second pulse timer
simultaneously. During the display test the following events take place.
1. The A/D power control line (U2-3) is set high by the microprocessor to turn on the power to U1.
Model 600 7
Page 10
Diatek, A Welch Allyn Company
2. The low battery detector output (Ul-9) is tested by the microprocessor. A low logic level on Ul-9
indicates a low battery condition (less than 3.0 volts).
3. The horn drive signal (U2-11) goes high activating the horn test for 0.1 second.
4. The backlight switch, normal/monitor switch and F/C switches are tested by the microprocessor.
5. A calibration cycle is performed.
6. The calibration test is performed.
7. The microprocessor memory test is performed.
8. The probe resistance is tested for an open or shorted condition.
Following the events which take place during the display test, a continuous monitor mode temperature
measurement or a predict mode temperature taking cycle is started.
Probe Temperature Measurement
Q3-Q6, Q8, R3-R5, R-16, C2 and U1 comprise a unique resistance to pulse width conversion circuit
which allows any one of 4 resistance’s to be measured by the microprocessor. The circuit allows the
microprocessor to select precision resistors with equivalent temperatures at opposite ends of the
temperature measurement range and measure their relative pulse widths.
The microprocessor sets U2- 16 to 19 high as required to select the appropriate resistance to be
measured. R3 provides a pulse width calibration at 93.2 °F, R5 provides calibration at 106.9 °F and R3
is used for a calibration test at 100.5 °F. A ratiometeric calculation is used to compute the probe
resistance from its pulse width relative to those provided by R3 and R5. The accuracy of each
calibration resistor is .05 °F. A resistance to pulse width conversion is initiated by the microprocessor
setting U2-64 high for approximately 0.5 seconds with the appropriate FET switch selected sometime
within that period. U2-64 is then set low and the time from this transition until the A/D output (U1-2)
goes high is measured by the microprocessor. The crystal X1 provides the time base for the pulse
width measurements. The probe temperature is computed using the probe resistance value obtained
from the ratiometeric pulse width calculations.
Monitor Mode Operation
In the monitor mode a new probe temperature measurement is completed every 1.5 seconds and a
new calibration cycle is completed every 3 seconds. The computed probe temperature is displayed
directly on the liquid crystal display and will follow both upward and downward movement.
Normal Mode Operation
In the normal mode. a new probe temperature measurement is completed every 1.5 seconds. At least
one calibration cycle is performed at the start of a predict cycle and continue every 3 seconds until the
probe temperature rises above 84.0 °F. The calibration cycle is stopped at this point to reduce
quantizing errors associated with the measurement of the slowly changing probe temperature.
The normal mode displayed temperature is the sum of the actual probe temperature and a computed
correction factor which is based on the shape of the changing temperature curve at that point in time.
The values of the correction factor can vary from 0 °F to 2.3 °F with a typical value when the horn
sounds of about 1 °F. During the display test prior to starting a normal mode temperature cycle, the
ambient temperature of the probe is measured and is used in the correction factor computation to
adjust for differing probe starting conditions. The normal mode display is peak reading and therefore
the highest temperature is displayed even though the present predicted probe temperature may drop.
8 Model 600
Page 11
Technical Manual
The normal mode temperature cycle is terminated when the predicted temperature remains stable for
several seconds.
SELF TESTS
Internal Calibration Test
The calibration test is performed only once during a temperature taking cycle and occurs during the
display test. Upon completion of the first calibration cycle, the resistance of R4 is measured and
compared against limits stored in the microprocessor memory. The specified limits are 5740 and 5780
ohms. If the resistance calculated by the microprocessor when the pulse width of R4 is measured does
not fall within these limits, the malfunction error is displayed.
Internal Microprocessor Memory Test
The microprocessor memory test is performed only once during a temperature taking cycle and occurs
during the display test. Each 8 bit byte of program memory is divided into two 4 bit nibbles which are
summed. The total sum of all nibbles and a special check sum compensation nibble must be O or the
malfunction error is displayed.
Broken Probe Test
Each probe resistance sample that is taken is checked to see that it lies between 2000 and 60,000
ohms. A resistance value outside of these limits will cause a broken probe error to be displayed.
DISPLAY
Display Voltage Reference
Diodes CR2-CR6. Q7, R61 and R7 create the display voltage references of about (V+)—1 volt at U225 (V+)—2 volts at U2-24 and (V+)—3 volts at U2-23.
Display
The liquid crystal display is of the 4 backplane multiplexed type (quadraplex), requires a regulated
operating voltage, and is driven directly by the microprocessor.
Horn
The microprocessor provides a control signal to U1-3 which is the feedback input for the horn driver
contained in U1. The horn driver output (U1-l) drives the horn (H1) at its self resonant frequency of
about 6 kHz.
Backlight
The microprocessor activates the backlight by setting U2-4 high. This signal is inverted and buffered
and reappears at U1-13 going low. A low level on U1-13 turns on the backlight inverter circuit
consisting of Q1, Q2, R1, R2, C5 and T1. The inverter supplies an AC voltage of about 80 volts and
300 Hz to the Electroluminescent panel BP1. CR7 blocks negative voltage spikes from entering U1-13.
Model 600 9
Page 12
Diatek, A Welch Allyn Company
Power Consumption
Without the thermometer or pulse timer active the average battery current should be under 50
microamperes. When the thermometer function is active the average battery current should be about 1
milliamp.
Maximum battery current with the backlight on should be about 25 milliamperes.
Low Battery Detection
When the battery voltage is reduced to 3.2 volts, Ul-9 goes low indicating a low battery condition to the
microprocessor which in turn causes the low battery indication to be displayed.
Pulse Timer Operation
Pressing the pulse timer switch activates the microprocessor interrupt to (U2-63) starting the pulse
timer display. The pulse timer input is independent from the temperature taking functions and may be
activated at any time. Starting the pulse timer causes the microprocessor to turn on the horn for 0.1
seconds at 0, 15 and 30 seconds and light one additional clock segment each second until the display
is fully lighted at 30 seconds at which time the clock display blanks. The timer cannot be restarted for
1.5 seconds following the last press of the timer switch but may be restarted at any later time.
10 Model 600
Page 13
Figure 1 - Block Diagram
Technical Manual
Model 600 11
Page 14
Diatek, A Welch Allyn Company
Figure 2 - Schematic
12 Model 600
Page 15
Figure 3 - Schematic (earlier serial numbers)
Technical Manual
Model 600 13
Page 16
Diatek, A Welch Allyn Company
Figure 4 - Printed Circuit Board Component Layout
14 Model 600
Page 17
Figure 5 - Final Assembly
Technical Manual
Model 600 15
Page 18
Diatek, A Welch Allyn Company
16 Model 600
Page 19
Figure 6 - Operating Controls and Components
Technical Manual
Model 600 17
Page 20
Diatek, A Welch Allyn Company
SPECIFICATIONS
Range: Normal and monitor modes
28.9°C to 42.2°C
84.0 °F to 108.0 °F
Accuracy: ±0.1 °C, ±0.2 °F (when tested in a calibrated water bath)
Battery Capacity: disposable batteries
three type AA cells
up to 1000 hours of continuous use
Dimensions: length 6.25 inches (159mm); width 3.7 inches (94mm); height 2.4 inches
(61mm)
weight: 10.5 ounces (298 grams)
Visual and Audible
Indicators:
case material: ABS Cycolac “T” grade plastic
digital temperature display
30 second pulse and respiration timer
instrument malfunction
broken probe
probe position
low battery
out of range temperature
18 Model 600
Page 21
Technical Manual
OPERATING INSTRUCTIONS
Set-up Procedure
1. Unpack the Model 600 Thermometer and probes, checking for any damage that may have
occurred during shipping.
2. Insert the plug of the probe to be used into the thermometer receptacle and then insert the probe
shaft into the probe storage channel of the thermometer. The thermometer will not turn on with the
probe disconnected.
3. Insert a box of 25 probe covers into the storage well of the thermometer.
4. Attach the 250 probe cover dispenser to the wall in a convenient location.
Preparation for temperature measurement:
1. Place the carrying strap around your neck with the instrument display facing you.
2. Check that sufficient probe covers remain for a round of temperature taking.
3. Select the desired Fahrenheit or Celsius display by setting the °F/ °C slide switch to the appropriate
position.
4. Select the mode of temperature measurement.
Normal Mode Operation
The normal mode of operation provides a rapid means of oral or rectal temperature taking under most
conditions.
Set the normal/monitor slide switch to the normal position. Withdraw the probe from the storage
channel and observe the 6 second display test ensuring that no display segments are missing. The unit
will then display 84.0 °F (28.9 °C) with the low temperature arrow ON until the probe rises above that
temperature.
Oral Temperature Measurement
Load a probe cover onto the probe by holding the probe collar with the thumb and forefinger being
careful not to hold or press the ejection button.
Insert the probe tip gently into patient’s slightly open mouth. Carefully slide probe under the tongue on
either side of the mouth to reach the sublingual artery.
Have the patient close lips around the probe.
Hold the probe during the entire temperature measurement process and keep the probe tip in contact
with tissue at all times.
During the temperature taking cycle, a continually increasing temperature should be observed on the
display. When the final temperature has been reached, a tone will sound and an “F” or “C” will be
displayed to the right of the numbers.
After temperature measurement is complete, eject the probe cover by firmly pressing the ejection
button on the probe. Insert into the probe channel to clear the display in preparation for another
temperature.
Model 600 19
Page 22
Diatek, A Welch Allyn Company
Rectal Temperature Measurement
Exchange the blue oral probe for the red rectal probe by removing the connector plug from the
thermometer and the probe from the storage channel. Complete the exchange by placing the rectal
probe in the storage channel and plugging the connector into the thermometer.
Load a probe cover and observe the thermometer start up display as in the oral procedure.
Separate the buttocks with one hand. Apply lubricant if necessary. Using the other hand, gently insert
the probe only 1 cm (3/8 inch). The insertion depth should be less in infants and small children.
Tilt the probe so the tip is touching tissue and continue to keep the buttocks separated.
Monitor Mode Operation
Monitor mode operation is normally used for longer term monitoring or when difficult situations prevent
accurate temperatures from being taken in the predict mode. The probe must be in place against
tissue for at least 3 minutes for accurate temperature measurement. Because of ambient temperature
influence and other factors, monitoring temperatures may not be identical to predict temperatures. The
fluctuation in temperature is the important standard to be observed during monitoring.
To take a temperature in the monitor mode, set the normal/monitor switch to the monitor position.
Insert the continuous monitor probe connector. Connect the desired sensor type to the thermometer
causing the 6 second display test to appear. Verify that no display symbols are missing and then attach
the probe to the patient as required. Once the temperature readout has been allowed 3 minutes to
stabilize, the patient may be continuously monitored as long as is necessary.
The symbol “M” on the display indicates that the unit is operating in monitor mode. The Model 600 will
turn off after 5 minutes if a temperature above 84.0 °F (28.9 °C) is not sensed.
Backlight Operation
The display backlight is used to allow the display to be read in poorly lighted areas. This function
should not be used unnecessarily as it will shorten the thermometer battery life.
Pressing the backlight switch any time the thermometer function is active will cause the backlight to
turn on as long as the button is being pressed. In the predict mode, activating the backlight prior to the
horn sounding causes the backlight to activate for 5 seconds after the horn sounds.
Pulse Timer
The pulse timer may be used to determine a patient’s pulse or respiration rate.
Press the pulse timer switch once the pulse or breath has been located. The timer will beep at 0, 15,
and 30 seconds. The number of pulses or breaths noted in 15 seconds should be multiplied by 4 to
obtain the pulse or respiration rate per minute.
The number of pulses or breaths noted in 30 seconds should be multiplied by 2 for the pulse or
respiration rate per minute.
The timer may be restarted at any time by pressing the pulse timer switch.
°F/°C Conversion
The °F/°C switch may be changed at any time to allow reading in Fahrenheit or Celsius scales.
20 Model 600
Page 23
Technical Manual
Error Indicators
When any of the following errors occur, a tone will sound twice for .1 seconds and the appropriate error
indicator will be flashing on and off (.5 seconds). Except for probe position error, no temperature will be
displayed while in the error mode and the unit will shut off in 5 minutes.
Horn will repeat the double beep every 10 seconds if error is not rectified.
Broken Probe
This error is intended to indicate that the probe will not function correctly and should be replaced.
Low Batteries
The purpose of the low battery indication is to preclude an improper reading, and to notify the user to
change batteries.
The following conditions will display a low battery error and prevent a temperature or timer display.
1. A low battery condition any time during monitor mode, regardless of pulse time.
2. A low battery condition existing prior to starting a predict mode temperature or activating the pulse
timer.
Note:
progress to be terminated.
Activating the pulse timer when a low battery condition exists will cause a predict temperature in
Probe Position Error
The “probe position error” is an indicator that appears whenever there is a rapid drop in temperature.
This can be the result of excessive probe movement or poor tissue contact. No audible tone will sound
for this error indication, however, a visual indicator will activate.
Temperature display is unaffected by this indicator, except that it will not update until temperature
rises.
Malfunction
The “Malfunction” error indicator activates after the self check whenever the thermometer will not
function correctly (does not include probe and battery malfunctions).
Self Tests
Initial Power Up Display
A special display test is performed each time a new set of batteries is installed. Upon inserting
batteries, all display segments are sequentially turned on for 0.4 seconds. The complete test requires
25 seconds and happens only when the batteries are changed.
Calibration Check
Each time the thermometer is turned on, an internal check for proper calibration is made at 100.5 °F
during the display test. A malfunction error will be indicated if the thermometer calibration is in error by
more than 0.2 °F.
Model 600 21
Page 24
Diatek, A Welch Allyn Company
Microprocessor Self Check
Each time the thermometer is turned on, an internal check for proper microprocessor operation,
including a test of the entire program, is made during the display test. A malfunction error will be
indicated if any faults are located.
Cleaning and Sterilization
The Model 600 unit and probes should periodically be cleaned by wiping it with an alcohol soaked cloth
or pad, warm water or non-staining disinfectant.
Do not autoclave or immerse the Model 600 unit.
Under conditions where an alcohol wipe or germicidal wipe are inadequate, the unit may be sterilized in
Ethylene Oxide (ETO). This is to be done at no more than 100 °F and 85% humidity. It is to
emphasized that this procedure is to be used only when absolutely necessary. It is imperative that the
batteries must be removed from the unit before ETO sterilization.
Battery Replacement
Remove the battery access screw by turning it counter clockwise with a Phillips screwdriver.
Slide the battery access cover away from the battery access label to expose the batteries.
Install 3 new AA batteries paying special attention to the + and - marks in the battery compartment.
Slide the cover back into place and install the screw, turning it clockwise.
As soon as the batteries are installed, a special display test is activated which sequentially lights then
extinguishes each display segment. The entire test lasts about 25 seconds. NOTE: if the horn is
activated by installing new batteries allow the display test to finish, then activate the pulse timer to reset
the horn.
Calibration Key Procedure
1. Remove probe plug and insert calibration key.
2. Place switch in Monitor Mode.
3. Install and remove probe from probe guide to reset thermometer.
4. Wait for the display test, then observe display.
5. Display should read 36.6 ± 0.1 °C or 97.3 ± 0.2 °F
6. Install probe in probe guide to turn unit off.
7. Remove calibration key and insert probe plug.
22 Model 600
Page 25
Technical Manual
Test Procedure
Power Up Display Test
1. Install a new set of batteries.
2. Immediately upon inserting the last battery, the display test will start.
3. Observe all display segments as they are sequentially lighted and then extinguished. Every
segment must be visible.
4. If the horn sounds when the batteries are installed, wait for the display test to be completed and
then press the timer switch to reset the horn.
Startup Display Test and Calibration Check
1. Set the normal/monitor switch to the monitor position.
2. Insert a calibration plug into the thermometer.
3. Observe the startup display test and check that all segments except the timer are lighted.
4. Following the display test, the unit should indicate the temperature stated on the calibration plug.
5. Note also that the horn sounds for a brief period as a test.
Switch Tests
With the thermometer on and the calibration plug installed, activate the °F/°C, backlight, and timer
switches and observe that the proper response is obtained.
Insert and remove a probe to test the probe switch action.
Placing the normal/monitor switch in the normal mode should cause the “M” to not be displayed when
the unit is turned on.
Low Battery Indicator
1. Set a variable DC power supply to 5 volts and then connect it to the thermometer in place of the
batteries.
2. With a calibration plug installed and a temperature being displayed, slowly reduce the power supply
voltage until the low battery condition is indicated. The power supply voltage must be 3.0+.3 volts.
Power Consumption
1. Set power supply at 5 volts.
2. Remove cal plug and let timer run out so that no display is showing.
3. The average current should be less than 50 microamperes.
4. Set switch to monitor mode.
5. Install probe or calibration plug.
6. The average current should be less than 1.5 milliamperes.
M9600 Procedure
The M9600 Calibration Tester provides a convenient means of testing the entire thermometer system
(instrument and probe). The 9600 must be warmed up and stable at one of the two available
Model 600 23
Page 26
Diatek, A Welch Allyn Company
temperature settings. The thermistor based instrument under test must be in Monitor mode and no
probe cover loaded. The probe is inserted into the small hole in the dry heat well of the 9600 and
allowed to settle for 2 minutes to the final temperature. The reading on the thermometer must be
within the range specified on the 9600. Refer to the M9600 Operation Manual for complete
instructions.
Note:
All Diatek thermometers (thermistor and infrared ear thermometers can be tested in the
M9600.)
If you are having problems with the use of the M9600, refer to the Troubleshooting section in the
M9600 Operation Manual.
MODEL 600 TROUBLESHOOTING
GENERAL
SYMPTOM PROBLEM TREATMENT
No Display (Temp or Timer) or
low Battery Indication
Batteries Low or Incorrectly
Installed
Replace Batteries
No Temperature Display, TimerOKProbe Plug Bad or Not Seated
Probe Switch Not Activating
Missing or Faded Display
Segments
Broken Probe Indication Defective Probe
Malfunction Indication Unit Cannot Self Calibrate or
Broken LCD Frame, Bad LCD,
LCD Connector Flex Strip,
Solder Bridge or U2
Bad Q6 FET
Microprocessor has a
Malfunction
Certain Broken Probe
Conditions
Reconnect or Replace Probe
Replace S1
Locate and Repair
Replace Probe
Replace Q6
Clean Main PC Board
Replace Q3, Q4, Q5, C2, R3,
R4, R5, or U2
Replace Probe
24 Model 600
Page 27
Technical Manual
MODEL 600 TROUBLESHOOTING (PCB ASSEMBLY)
No Display:
Processor clocks U2-59, 21
Display enable U2-10
Display Voltages U2-23, 24, 25
Malfunction Error or Off Cal:
With power off, measure R3, R4, and R5
Values must be within + 5 ohms
FET Checks:
If malfunction error is showing check for any FET leak age by connecting the voltmeter across R3, R5
and probe with a cal plug in place. (The meter must not be g rounded.) The voltag e across the re sistors
must not be measurable (10 millivolts or less).
Ground the gate of Q6 and perform the same test.
Check for FET Turn On:
Malfunction error: Measure the low state voltage of each FET as it turns on following a probe switch
activation check Q3, Q4, and Q5. The low state voltage should be less than 20 millivolts.
Off Cal: Check Q3, Q4, Q5 and Q6 as above.
If the above tests fail to show the failed component, replace C2, then U1.
Missing or Faded LCD Segments:
1. Loose LCD frame
2. Dirt or oil under zebra strip
3. Exposed PCB clad running between pads on LCD board
4. Solder bridges
5. Broken flex cable
Unstable monitor cal or bad predict test:
(2 °F add on) or malfunction: replace C2.
Malfunction error, probe switch not working correctly:
S1 shorted to R3 trace under S1 switch—lift switch off PCB slightly.
Backlight:
Must be tested with a monitor mode temperature being displayed.
Weak Backlight:
Check transformer type or C5.
No Backlight:
1. Check for square wave on Q1 or Q2 collector , if square wave is present, check continuity of T1
secondary about 1K ohms)
2. U1-13 and Q1, Q2 emitters must go low
3. Bad or open C5 will cause the square wave to be much too high in frequency (should be about 400
Hz)
4. U1-12 must go high
5. U2-12 must go low
Horn:
1. U2-64 must go high
2. RN1-D or E
Model 600 25
Page 28
Diatek, A Welch Allyn Company
PARTS LIST (units with serial numbers equal to or greater than 193309)
REFERENCE DESIGNATOR DESCRIPTION DIATEK P/N
U1 IC, MOG-3242 MONOCHIP 54124-000
U2 IC, UPD75036 G-12 MASK ROM 54123-000
C1 CAP, 47µF/6.3V 20% TANT 46090-0000
C2 CAP 15µF/10-16V 10% TANT 46123-000
C3, C6, C7 CAP, 33pF MICA 46091-000
C4 CAP, .47µF/35V 20% TANT 46013-000
C5 CAP, .01µF/100V CERAMIC 46094-0000
C11 CAP, .1µF 50V 46109-0000
CR2, CR3, CR4, CR5, CR6, CR7 DIODE, IN459 44011-0000
Q1, Q2, Q7 TRANSISTOR, PN2222 50004-0000
Q3, Q4, Q5, Q6 FET, PWR VN10KM 50021-0000
Q8 TRANSISTOR, SIGNAL, 2N4124 50014-0000
R1, R2 RES, 18K, 1/4W 5% 40040-1840
R3 RES, 6810 1/8W .1% RN50 40266-811
R4 RES, 5760 1/8W .1% RN50 40265-761
R5 RES, 4990 1/8W .1% RN50 40264-9910
R6 RES, 200K 1/4W 5% 40040-4730
R7 RES, 33K 1/4W 5% 40040-3340
R8, R9, R12 RES, 100K 1/4W 5% 40014-000
R10 RES, 4.3 OHM 1/4W 5% 40040-430
R11 RES, 10K 1/4W 5% 40040-1040
R13, R15 RES, 2M 1/4W 5% 40040-206
RN1 RES SIP 100K 1/10W 40259-000
S2, S3 SWITCH, SLIDE 58100-000
S4, S5 SWITCH, CONTACT 58096-000
S4, S5 CONTACT, BOTTOM 58097-000
J2 CABLE, FLEX 30 COND 58103-000
T1 TRANSFORMER 52005-000
X1 CRYSTAL 32.768 kHz 47006-000
J1 CONNECTOR, PROBE 58105-000
S1 SWITCH, PROBE 58101-000
LS1 HORN, PIEZO 58102-000
DS1 LCD DISPLAY 60011-000
DS2 LAMP, ELECTROLUMINESCENT 58104-000
ZEBRA FRAME 25092-000
CONNECTOR, ZEBRA 58112-000
C8, C9, C10 CAP, .01µF/100V 10% CERAMIC 46009-000
WINDOW DISPLAY 25103-000
BATTERY, AA ALKALINE 53009-000
SCREW, SELF-TAP 4 X 7/8 CSK 82° PLASTILOK 83035-000
R14 RES, 1 OHM 1/8W 5% CF 40040-011
PCB, DISPLAY 56048-000
26 Model 600
Page 29
Technical Manual
PCB, MODEL 600 THERMOMETER 56078-000
SCREW, MACH 4-40 X 1 1/16 PHD 83036-000
SCREW, THD ROLL #4 X 3/4 CSK 82° PLASTILOK (2) 83037-000
SCREW, THD ROLL #4 X 1/4 CSK 82° PLASTILOK (2) 83021-000
PARTS LIST (units with serial numbers less than 193309)
REFERENCE DESIGNATOR DESCRIPTION DIATEK P/N
U1 IC, MOG-3242 MONOCHIP 54124-000
U2 IC, UPD75036 G-12 MASK ROM 54123-000
C1 CAP, 47µF/6.3V 20% TANT 46090-0000
C2 CAP 15µF/10-16V 10% TANT 46098-000
C3, C6, C7 CAP, 33pF MICA 46091-000
C4 CAP, .47µF/35V 20% TANT 46013-000
C5 CAP, .01µF/100V CERAMIC 46094-0000
C11 CAP, .1µF 50V 46109-0000
CR2, CR3, CR4, CR5, CR6, CR7 DIODE, IN459 44011-0000
Q1, Q2, Q7 TRANSISTOR, PN2222 50004-0000
Q3, Q4, Q5, Q6 FET, PWR VN10KM 50021-0000
R1, R2 RES, 18K, 1/4W 5% 40040-1840
R3 RES, 6810 1/8W .1% RN50 40266-811
R4 RES, 5760 1/8W .1% RN50 40265-761
R5 RES, 4990 1/8W .1% RN50 40264-9910
R6 RES, 200K 1/4W 5% 40040-2050
R7, R8, R9, R10, R12, R13 RES, 100K 1/4W 5% 40014-1050
R11 RES, 4.7K 1/4W 5% 40040-4730
R13, R15 RES, 2M 1/4W 5% 40040-206
S2, S3 SWITCH, SLIDE 58100-000
S4, S5 SWITCH, CONTACT 58096-000
S4, S5 CONTACT, BOTTOM 58097-000
J2 CABLE, FLEX 30 COND 58103-000
T1 TRANSFORMER 52005-000
X1 CRYSTAL 32.768 kHz 47006-000
J1 CONNECTOR, PROBE 58105-000
S1 SWITCH, PROBE 58101-000
LS1 HORN, PIEZO 58102-000
DS1 LCD DISPLAY 60011-000
DS2 LAMP, ELECTROLUMINESCENT 58104-000
ZEBRA FRAME 25092-000
CONNECTOR, ZEBRA 58112-000
C8, C9, C10 CAP, .01µF/100V 10% CERAMIC 46009-000
WINDOW DISPLAY 25103-000
BATTERY, AA ALKALINE 53009-000
SCREW, SELF-TAP 4 X 7/8 CSK 82° PLASTILOK 83035-000
R14 RES, 1 OHM 1/8W 5% CF 40040-011
PCB, DISPLAY 56048-000
Model 600 27
Page 30
Diatek, A Welch Allyn Company
PCB, MODEL 600 THERMOMETER 56078-000
SCREW, MACH 4-40 X 1 1/16 PHD 83036-000
SCREW, THD ROLL #4 X 3/4 CSK 82° PLASTILOK (2) 83037-000
SCREW, THD ROLL #4 X 1/4 CSK 82° PLASTILOK (2) 83021-000
RECOMMENDED SPARE PARTS FOR MODEL 600
(100 INSTRUMENTS PER YEAR)
REFERENCE DESIGNATOR DESCRIPTION DIATEK P/N QUANTITY
NECK STRAP ADJUSTOR 25085-000 2
FRONT CASE 25088-001 5
BACK CASE 25089-001 10
MID-FRAME 25090-000 2
BATTERY DOOR 25091-001 2
ZEBRA FRAME 25092-000 15
WINDOW 25103-000 4
DIODE, 1N459 44011-0000 4
C1 CAPACITOR 46090-0000 2
C2 CAP 15µF 10-16V/10% TANT 46123-000 2
X1 CRYSTAL 32.768 kHz 47006-000 4
Q1, Q2, Q7 TRANSISTOR, 2N2222 50004-0000 4
Q8 TRANSISTOR, 2N4124 50014-0000 2
Q3, Q4, Q5, Q6 FET, PWR VN10KM 50021-0000 2
T1 TRANSFORMER 52005-000 1
U2 IC, UPD75036 G-12 MASK ROM 54123-000 2
U1 IC, MOG-3242 MONOCHIP 54124-000 2
S4, S5 SWITCH, CONTACT 58096-000 4
S4 CONTACT, BOTTOM 58097-000 4
S2, S3 SWITCH, SLIDE 58100-000 4
S1 SWITCH, PROBE 58101-000 5
LS1 HORN 58102-000 4
J2 FLEXIBLE CABLE 58103-000 4
DS2 LAMP, ELECTROLUMINESCENT 58104-000 10
J1 CONNECTOR, PROBE 58105-000 6
CONNECTOR, ZEBRA 58112-000 10
BATTERY CONTACT, COMMON 58411-000 20
BATTERY CONTACT, POSITIVE 58412-000 10
BATTERY CONTACT, NEGATIVE 58413-000 10
DS1 LCD DISPLAY 60011-000 10
LABEL SET 70158-000 20
SERIAL NUMBER LABEL 70437-000 10
RED WIRE, 26 AWG STRANDED 80013-0002 2FT
BLACK WIRE, 26 AWG STRANDED 80013-001 2FT
TY-RAP 80038-0000 4
VINYL CORD, NECK STRAP 80080-000 2
28 Model 600
Page 31
Technical Manual
SCREW, THD-ROLL #4X1/4 P-PL-S-Z 83021-0000 4
SCREW, PLASTITE, 4-20 X 7/8 FLAT
HEAD 82 DEG PL-S-Z
SCREW, MACH 4-40 X 1 1/16 P-PL-S-Z 83036-0000 2
SCREW, PLASTITE 4-20 X 3/4 - FLAT
HEAD 82 DEG PL-S-Z
83035-000 2
83037-000 4
MODEL 600 PREVENTATIVE MAINTENANCE
The following suggested preventative maintenance is recommended to maximize uninterrupted service
with the Model 600 Thermometer.
Units which are in service on a regular basis should have the following preventative maintenance
performed every 18 months:
1. Visually inspect the thermometer and probe for physical damage which might cause future product
failure.
2. Clean unit if necessary and replace batteries according to the procedures found on page 22 of this
manual.
3. Perform the Power Up Display Test, Startup Display Test and Calibration Key Procedure found on
page 21 and 22 of the manual.
Units which are stored for extended period and not used should have the following preventative
maintenance performed every 36 months:
1. Replace batteries according to the procedures found on page 22 of this manual.
2. Perform the Power Up Display Test, Startup Display Test, and Calibration Plug Procedure found on
page 22 of this manual.
Model 600 29
Page 32
7420 Carroll Road, San Diego, California 92121 • (800) 854-2904 • (619) 621-6600 • FAX (619) 621-6610
70017-000H
Loading...