Future Design MCTB 4.3, Руководство пользователя

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MCTB
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Press the
Perform User Calibration Offset button to access the settings for applying an offset to the loop or
limit factory calibration. This is the recommended method of calibrating the inputs for users without special
calibration equipment and is suitable for most applications.
Press the
Perform Manual Calibration button to begin the factory calibration procedure for the selected loop
or limit input. This option is NOT recommended for users with limited calibration experience. Special high
accuracy equipment is required to properly calibrate the inputs to factory standards. Improper calibration could
render the device inoperable and require it to be sent back to the factory for repair.
Prior to performing any calibration procedure, read the documentation carefully and understand the steps
required to perform calibration. The loop and limit controls must be powered for a minimum of 30 minutes prior
to performing calibration in order to ensure that they have warmed up and are at normal operating temperature.
Required calibration sources:
Thermocouple Input: 0
– 100mV and K-Type 0.005% accuracy
RTD Input:
0
– 300ohm 0.005% accuracy
Voltage Input:
0
– 10VDC 0.005% accuracy
Milliamp Input:
0
– 20mA 0.005% accuracy
10.5.1 Loop Calibration Offset
The calibration offset provides a two-point offset; a low point offset and a high point offset. The two-point offset
constructs a straight line (linear calibration) between the two points. To insure greatest accuracy, it is best to
calibrate with the two points at the minimum and maximum operating ranges for the system.