Minco TI408, Руководство по эксплуатации

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Temperature Indicator Calibration
Calibration of the temperature indicator can be done in a number of ways; comparison to
another calibrated instrument, using decade box simulation, or in a controlled environment
such as an oil bath. The TI408 series indicator incorporates a calibration menu to adjust the
zero offset for each channel.
Controlled Environment / Comparison Method
The most accurate method of re-calibrating the indicator / sensor system is to place the
sensor(s) in a known environment such as an oil-bath or a calibration chamber and base all
measurements off of a known standard. Calibration using this method will account for any
lead-length or contact resistance, as well as any offset characteristics of the sensor. The
environment should have an accurate sensor or instrument (standard) with an accuracy of less
than or equal to 0.1°C from which all measurements will be based. To compare the calibration
of the indicator to another calibrated instrument or sensor, both sensors should be within 1
” of
each other. Set the temperature of the environment to the mid-point of the desired
measurement range. For example, if all measurements fall within the range of 120°C to 135°C,
set the environment to 127.5°C. Wait for the indicator and standard to stabilize before
proceeding. Once the system is stable, follow the calibration procedures below for each
channel to calibrate the indicator.
Decade Box
Connect a resistance decade box with a resolution of at least .01 ohms to the desired input
(CH1-
CH8) of the indicator. If unsure or concerned about the decade box’s accuracy, measure
the desired set-point using an accurate 4-wire ohmmeter. Set the decade box resistance to
simulate the mid-point of the desired measurement range. For example, if all measurements
fall within the range of 120°C to 135°C, simulate the resistance for 127.5°C (1488.92
W
for a PF
type sensor). Follow the instructions below to calibrate the indicator for each channel.