Nova-Tech 4635 TRACEABLE TWO-CHANNEL THERMOMETER User Manual
Nova-Tech Equipment
 
Traceable
®
is a registered trademark of Control Company ©2008 Control Company. 92-4135-00 Rev. 2 052008
 
SPECIFICATIONS 
Range: 
–58 to 2000°F (–50 to 1300°C)
Resolution:
1°
Accuracy:
±0.3% + 1°C
Probe:
(2) Type-K thermocouple naked bead probe with 4' lead
Sampling Rate: 2.5 times per second 
Display: 
3½ digit LCD, 5/8 inches high (1.5CM)
Failsafe:
Low battery indicator
Power:
9 volt alkaline battery
Accessories: 12 inch Velcro wrist strap, rubberized cover and a flip-out stand
FRONT PANEL QUICK REFERENCE 
 ON 
- Turns power on
 OFF - Turns power off 
 MAX - Records and updates maximum values 
 HOLD - "Freezes" the display 
 F/C - Selects the temperature to be displayed 
 
in either Fahrenheit or Celsius
T1
- Displays temperature reading from probe 1
T2
- Displays temperature reading from probe 2
 T1/T2 - Displays the difference in temperature 
 
between probe 1 and probe 2
OPERATION 
Insert the probe plugs into the receptacles located on the front of the thermometer. 
The plugs and receptacles are keyed with small and large pins. Make certain that the 
plugs are inserted correctly, do not force them. 
NOTE: Only one probe is required for normal operation.
Press the ON button to turn the unit on.
Press the F/C button to display the temperature in Fahrenheit (°F will appear on the 
display) or Celsius (°C will appear on the display). 
Press the T1 button to display the temperature of probe 1 
(T1 appears on the display). 
Press the T2 button to display the temperature of probe 2 
(T2 appears on the display). 
Place the probe tip in contact with the material to be measured and read the 
temperature on the display. 
MAX MODE 
In the MAX mode, the thermometer will display the highest temperature reading 
achieved. It does not display the current temperature if it falls below the MAX reading. 
Example: In the MAX mode
If the current temperature is...
The display will read...
42°F
42°F
60°F
60°F
40°F
60°F
Select the desired input (T1, T2 or T1-T2) then press the MAX button (MAX will appear 
on the display). The thermometer will display the maximum temperature reading on the 
LCD display. Press the MAX key again to exit MAX recording mode. 
HOLD 
Press the HOLD key to "freeze" the display at the current T1, T2 or T1-T2 reading (D-
H will appear in the display). Press the HOLD key again to return to the current 
reading. 
TEMPERATURE DIFFERENTIAL T1-T2 
Press the T1-T2 key to display the difference in temperature between probe 1 and 
probe 2. This feature takes the temperature being measured at probe 2 and subtracts 
it from the temperature being measured at probe 1 and displays the difference. 
NOTE: Two probes must be connected to the unit to use this feature. 
PROBES 
The probes supplied are ultra-fast response Type-K thermocouple naked bead probes 
with 4' leads and teflon insulation. Operating temperature range for these 
thermocouples is or 500°F (260°C ). 
An accessory stainless steel triple purpose probe with handle is available. An 
accessory surface probe is also available (see accessories). 
Longer leads and extensions may be used. The lead effect for 164 feet (50 meters) is 
generally less than 0.2°C with a limit of error of 2.2°C. Type-K wire and Type-K 
connectors must be used. 
OFFSET ADJUSTMENT (Fine tuning) 
The offset controls are set at the factory to allow for the variations found in standard 
thermocouples. By adjusting the offset controls, found below the thermocouple plugs, 
you can optimize measurement accuracy for a particular thermocouple (or pair of 
thermocouples) at a particular temperature. 
 
ADJUSTING FOR T1 OR T2 MEASUREMENTS 
1. 
Plug in the T1/T2 thermocouple and turn the thermometer ON. Press the 
appropriate T1/T2 key to display reading. 
2.
Place the thermocouple in a known stable temperature environment at or near 
the temperature you wish to measure. Allow the reading to stabilize. 
3.
Slowly adjust the T1/T2 OFFSET control that corresponds to the selected input 
until the thermometer reading matches the temperature of the known 
environment. (Allow sufficient time between adjustments to allow for 
measurement lag). 
4.
The calibration of the thermometer-thermocouple combination is now optimized 
(fine-tuned) for measurement near the temperature used in step 2. 
ZERO ADJUSTMENT FOR T1-T2 MEASUREMENTS: 
1. 
Plug in both the T1 and T2 thermocouples.
2.
Turn the thermometer on and press the T1-T2 button.
3.
Place the thermocouples in a known stable temperature environment at or near 
the temperature you wish to measure and allow the reading to stabilize. 
4.
Slowly adjust either T1 or T2 (but not both) of the OFFSET controls until the 
thermometer reads "0". (Allow sufficient time between adjustments to allow for 
measurement lag). 
5.
The thermometer-thermocouple combination is now set for differential 
temperature measurement near the temperature used in step 3. 
WRIST STRAP AND STAND 
The unit is supplied with a Velcro wrist strap that attaches through the two slots in the 
back of the rubberized casing. Remove the rubberized cover and slip the end of the 
strap through the slots, Velcro side out, fasten at the buckle. 
A bench stand is also supplied with this unit and is part of the rubberized case. Locate 
the rectangular opening at the back of the unit. Place your fingernail under the opening 
and flip the stand out. To close the stand, simply snap it shut. 
TRACEABLE
®
TWO-CHANNEL THERMOMETER INSTRUCTIONS