Panametrics CTF878, Руководство по обслуживанию

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Chapter 3.
20 Model CTF878 Service Manual
3.1.3 Testing and Calibrating Analog Outputs
The Calibration/Test option can be used to test and calibrate the analog outputs. To enter the option, scroll to the
Main Board or to an AnologOut option under the Calibrate / Test Menu and press [ENTER] . The screen appears similar
to Figure 24 below.
Figure 24: Analog Outputs Test / Calibration Window
3.1.3.1 Testing Analog Outputs
To test an Analog Output, you must connect a digital multimeter to the analog output. Proceeding as above, select
the Test AnalogOut option (see Figure 24 above) for the Analog Output to be tested, and press [
ENTER
]. A clock
appears in the middle of the screen with the message “
TESTING IO”
below it, while the multimeter is displaying the
test current output. The test current output value should go through the full range. When the test is complete, the
screen returns to Operate Mode.
Repeat the process to test additional Analog Outputs.
3.1.3.2 Calibrating Analog Outputs
The Analog Output calibration procedure consists of calibrating the analog output zero point (0 or 4 mA) and then
calibrating the full scale point (20 mA). First you will enter the setpoint, and then the actual value derived from an
ammeter or digital voltmeter. The analog outputs have a resolution of ±5.0 µA.
To calibrate an Analog Output, proceed as above, select the desired Calibrate AnalogOut option, and press [
ENTER ].
The screen appears as shown in Figure 25 on page 21. Proceed as follows:
1. Connect a digital multimeter to the analog output and step through the options using the arrow keys.
Site Program Meter Logging
Signal Setup
Error Limits
Test
Factory Defaults
Flash Update
0 50
Diagnostics
AnalogIns (2)
Calibrate AnalogOut(0:A)
Test AnalogOut(0:B)
Calibrate AnalogOut(0:B)
15.38
34
Service
Velocity, m/s
Corr SNR
Calibrate / Test
Main Board (0)
Test AnalogOut(0:A)