28
Measurement error of reflow checker
④
Usage frequency of board to be measured
If a board on which no part is mounted, not of a production board, is used for measurement purpose, the
measured temperature may become different from the actual temperature.
If a board prepared for measurement is passed through the reflow oven repeatedly, the measured
temperature may become higher than the production board because of drying out and discoloration
(blackening) which affect thermal capacity of the board.
Temperature calibration
The accuracy of the reflow checker can be maintained by conducting temperature calibration more than
once a year every other year. For correct temperature calibration, please ask us.
Though difficult to perform full-scale temperature calibration, the customer is capable of using the
following method for temperature confirmation. This gives a rough but reproducible indication.
A. Measuring the temperature of water at room temperature
Pour water of room temperature into a beaker, and record the temperature with a standard glass
thermometer while stirring. (Electrical or electronic type thermometer can cause potential variation,
and must not be used.)
B. Measuring the temperature of steam of boiling water
Boil water in a kettle, and record the temperature of the steam. (Do not dip the thermometer in the
water.)
Note that just 100
℃
indication may not be obtained due to the reasons of atmospheric pressure,
etc.
C. Recording the solidifying temperature of eutectic solder
Melt the solder once, and record its solidifying temperature. The temperature dropping rate will
change near the eutectic point (standard 183
℃
) of the solder.
In addition to a standard voltage generator that may be possessed by a customer, temperature
calibration further needs a cryoscope and its special thermocouple. It is therefore recommended to
leave the temperature calibration to our hand.
IV-3
Troubleshooting
IV-3-1
Failed to initialize the Bluetooth module
Q. Monitor LED is flashing in light blue-yellow and unbale to use the device.
A. Failed to initialize the Bluetooth module. While the LED is flashing, press the button to forcedly
initialize it.