Emerson 2200S Manuel D’Utilisation

116

Improper calibration can cause the transmitter to send unexpected output values. If the transmitter 
appears to be operating correctly but sends inaccurate output values, an improper calibration may be 
the cause.

Micro Motion calibrates every transmitter at the factory. Therefore, you should suspect improper 
calibration only if the transmitter has been calibrated after it was shipped from the factory. Before 
performing a calibration, consider meter validation or meter verification and select the appropriate 
procedure (see Section 9.2). Contact Micro Motion customer service for assistance.

Some status alarms that indicate a sensor failure or overrange condition can be caused by problems 
other than a failed sensor. You can diagnose sensor failure or overrange status alarms by checking the 
flowmeter test points. The test points include left and right pickoff voltages, drive gain, and tube 
frequency. These values describe the current operation of the sensor.

You can obtain the test points with a Communicator or ProLink II.

To obtain the test points with a Communicator:

1. Select 

.

2. Select 

.

3. Record the values displayed for 

, 

, 

, and 

To obtain the test points with ProLink II:

1. Select 

 from the 

 menu.

2. Record the values displayed for 

, 

, 

, and 

.

Problems with drive gain can appear in several different forms:

•

Saturated or excessive (near 100%) drive gain 

•

Erratic drive gain (e.g., rapid shifting from positive to negative)

•

Negative drive gain

See Table 10-5 for a list of possible problems and remedies.