GE CTF878 Troubleshooting guide

GE
Sensing
Model CTF878
Clamp-On Tag Flowmeter
User’s Service Manual

GE
Sensing
Model CTF878
Clamp-On Tag Flowmeter
User’s Service Manual
910-254SA4
February 2009

iii
February 2009
Warranty Each instrument manufactured by GE Sensing, Inc. is warranted to be
free from defects in material and workmanship. Liability under this
warranty is limited to restoring the instrument to normal operation or
replacing the instrument, at the sole discretion of GE. Fuses and
batteries are specifically excluded from any liability. This warranty is
effective from the date of delivery to the original purchaser. If GE
determines that the equipment was defective, the warranty period is:
•one year for general electronic failures of the instrument
•one year for mechanical failures of the sensor
If GE determines that the equipment was damaged by misuse,
improper installation, the use of unauthorized replacement parts, or
operating conditions outside the guidelines specified by GE, the
repairs are not covered under this warranty.
The warranties set forth herein are exclusive and are in lieu of
all other warranties whether statutory, express or implied
(including warranties of merchantability and fitness for a
particular purpose, and warranties arising from course of
dealing or usage or trade).
Return Policy If a GE Sensing, Inc. instrument malfunctions within the warranty
period, the following procedure must be completed:
1. Notify GE Sensing, Inc., giving full details of the problem, and
provide the model number and serial number of the instrument. If
the nature of the problem indicates the need for factory service,
GE Infrastructure Sensing, Inc. will issue a RETURN
AUTHORIZATION number (RA), and shipping instructions for the
return of the instrument to a service center will be provided.
2. If GE instructs you to send your instrument to a service center, it
must be shipped prepaid to the authorized repair station indicated
in the shipping instructions.
3. Upon receipt, GE will evaluate the instrument to determine the
cause of the malfunction.
Then, one of the following courses of action will then be taken:
•If the damage is covered under the terms of the warranty, the
instrument will be repaired at no cost to the owner and returned.
•If GE determines that the damage is not covered under the terms
of the warranty, or if the warranty has expired, an estimate for the
cost of the repairs at standard rates will be provided. Upon receipt
of the owner’s approval to proceed, the instrument will be repaired
and returned.

v
February 2009
Table of Contents
Chapter 1: Diagnostics
Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-1
Entering the Service Menu . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-1
Displaying Diagnostic Parameters. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-2
Signal Setup. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-3
Setting Up Signal Parameters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-3
Setting Error Limits. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-5
The Test Option . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-7
Testing the Screen. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-8
Testing the Keys . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-9
Testing the Watchdog Timer Circuit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-10
Chapter 2: Resetting and Updating
Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-1
Entering the Service Menu . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-1
Resetting to Factory Default Parameters. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-2
Updating CTF878 Software. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-3
Preparation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-4
Setting Up the PC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-5
Installing New Software . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-7
Completion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-10
Chapter 3: Calibration
Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3-1
Entering the Calibration/Test Menu . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3-1
Testing and Calibrating Analog Outputs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3-2
Testing Analog Outputs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3-2
Calibrating Analog Outputs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3-2
Testing and Calibrating Analog Inputs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3-4
Testing Analog Inputs. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3-4
Calibrating Analog Inputs. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3-5
Testing and Calibrating Digital Outputs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3-6
Testing Digital Outputs. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3-6
Calibrating (verifying the accuracy of) Digital Outputs. . . . . . . . . . . . . . . . . . . . . . . . . . . . .3-7
Testing and Calibrating RTD’s . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3-8
Testing RTD’s. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3-8
Calibrating RTD’s. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3-9
Testing EEPROM’s . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3-10

February 2009
vi
Table of Contents (cont.)
Chapter 4: Troubleshooting
Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-1
Error Code Messages . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-1
Displaying Diagnostic Parameters. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-3
Pipe/Fluid Problems. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-4
Gas Problems. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-4
Pipe Problems . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-5
Transducer Problems . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-6
Chapter 5: Parts Replacement
Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-1
Replacing the Fuse. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-2
Removing the Printed Circuit Board . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-3
Installing an Option Card. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-4
Installing the Printed Circuit Board . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-5
Replacing the LCD Display. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-7
Spare Parts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-8
Appendix A: Service Record
Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A-1
Data Entry . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A-1

Chapter 1

Diagnostics
Introduction. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-1
Entering the Service Menu . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-1
Displaying Diagnostic Parameters. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-2
Signal Setup. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-3
Setting Error Limits . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-5
The Test Option. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-7

Diagnostics 1-1
February 2009
Introduction For convenience, the CTF878 offers a Service Menu (see the Service
Menu Map, Figure 3-10 on page 3-11). This menu enables the user to
perform a variety of functions that might occasionally be required.
Those covered in this chapter include:
•run diagnostics
•set up signal and data processing parameters
•define error limits
•test the CTF878 screen and keys
•diagnose setup problems
Entering the Service
Menu To enter the Service Menu, press the [MENU] key at the lower right of
the CTF878 keypad. The Menu Bar replaces the Status Bar at the top
of the screen. Press the [X] arrow key to scroll from the Site Menu to
the Service Menu. At the Service Menu, press [ENTER]. The screen
appears similar to Figure 1-1 below.
Figure 1-1: Service Menu
To scroll to a particular option, press the [T] or [S] arrow keys until
you reach the option. Then press [ENTER] to open the option window.
When entering parameters in an option, press:
•the [T] key to step through the available parameters.
•the [S] key to scroll back to a previously entered parameter.
•the [F2] key (Cancel) or the [ESC] key to exit an option at any time
and return to Operate Mode without changing the parameters.
Units Test
Site Program Meter Logging
Signal Setup
Error Limits
Test
Factory Defaults
Flash Update
Calibrate/Test
Test EEProm
34
0 50 100
15.38
Service
Diagnostics
Velocity, m/s
Corr SNR

February 2009
1-2 Diagnostics
Displaying Diagnostic
Parameters The Diagnostics option enables you to view current diagnostic
parameters without having to open a display window in Operate
Mode. To enter the option, scroll to the Diagnostics entry on the
Service Menu and press [ENTER]. The screen appears similar to
Figure 1-2 below.
Figure 1-2: Diagnostics Tests Window
Press [F2] (Cancel) or [F3] (OK) to close the window and return to
Operate Mode.
Note: For an explanation of diagnostic parameters, refer to
Chapter 4, Troubleshooting.
OKCancel
Meter Error 0x0004
Carr A
Carr G
I A
Q A
Mod G
TAU
Corr SNR
Up
1000
9.72
390
680
–3.13
19.25
34
–4.65
992
7.26
487
586
Down
Diagnostic Tests

Diagnostics 1-3
February 2009
Signal Setup The Signal Setup option enables you to set parameters that affect the
flowmeter’s signal processing and outputs:
•Zero Cutoff
•Velocity Averaging
•Errors Allowed
To enter the option, scroll to the Signal Setup entry on the Service
Menu and press [ENTER]. The screen appears similar to Figure 1-3
below.
Figure 1-3: Signal Parameter Window
Setting Up Signal
Parameters
1. Press the [T] arrow key to enter the window.
2. The first prompt allows you to select or not select Reverse Flow.
a. Press [ENTER] to select Reverse Flow, and press the [T] arrow
key to enter the next prompt, or
b. Press [ENTER] again to deselect Reverse Flow, and press the
[T] arrow key to enter the next prompt.
AgcMgc CCorr Avg LP Filter
.5Zero Cutoff m/s
OKCancel
Velocity Averaging
Errors Allowed 2
None
Reverse Flow
Signal Setup
Signal

February 2009
1-4 Diagnostics
Setting up Signal
Parameters (cont.)
3. The next prompt asks for the Zero Cutoff. Near “zero” flow, the
CTF878 may have fluctuating readings due to insufficient flow
information. The zero cutoff causes velocity measurements less
than the cutoff to be reported as zero. To set the cutoff:
a. Press [ENTER] to open the text box.
b. Use the numeric keys to enter the desired value.
c. Press [ENTER] to confirm your entry.
d. Press the [T] arrow key to enter the next prompt.
4. The next prompt asks for Velocity Averaging.
a. Press [ENTER] to open the drop-down list (from 2 to 100).
b. Use the [T] or [S] arrow keys to scroll to the desired number
of velocity measurements to average together to smooth out
noise in the system.
c. Press [ENTER] to confirm your selection.
d. Press the [T] arrow key to enter the next prompt.
5. The final prompt, Errors Allowed, specifies the number of errors
the meter can record before displaying an error message. (The
default is 2.)
a. Press [ENTER] to open the text box.
b. Use the numeric keys to enter the desired value.
c. Press [ENTER] to confirm your entry.
You have finished entering data in the Signal Parameter window. To
leave this window,
•Press the [S] key to return to the Signal Parameter tab, and the
[X] arrow key to move to the other tabs. When the desired tab
is highlighted, press [ENTER]to view its contents.
•Or, press [F2] (Cancel) to return to Operate Mode without
confirming the changes.
•Or, press [F3] (OK) to confirm the new data. The CTF878
returns to Operate Mode.
IMPORTANT: Do not change the remaining Signal Setup options:
AgcMgc - Automatic or Manual Gain Control
CCorr Avg - Cross Correlation Average
LP Filter - Low Pass (Digital) Filter
They should be set up only by field service engineers.

Diagnostics 1-5
February 2009
Setting Error Limits The Error Limits option enables you to set limits for the signals
received from the transducers and the limits for some outputs. When
the parameter falls outside the programmed limits, an error indication
appears. To enter this option, scroll to the Error Limits entry on the
Service Menu and press [ENTER]. The screen appears similar to
Figure 1-4 below.
Figure 1-4: Signal Error Limits Option
1. The first prompt asks for the minimum error limit for the
correlation signal-to-noise ratio (SNR) calculated by the CTF878.
The default value is 10. The E8: SNR error message appears if the
SNR falls below the limit programmed here.
IMPORTANT: SNR Min should be changed from factory default
settings only if absolutely necessary. These settings
may be changed by qualified field service engineers,
only.
To enter the minimum SNR:
a. Press [ENTER] to open the text box.
b. Use the numeric keys to enter the desired value.
c. Press [ENTER] to confirm your entry.
d. Press the [X] or [T] key to move to the next limit.
2. The next prompt calls for the low and high velocity limits. The
E9: VELOCITY RANGE error message appears if the velocity
falls outside these limits. Repeat Step 1 above to enter the desired
limits.
Min Max
OKCancel
SNR Min
–100Velocity m/s100
15Acceleration m/s
75Carrier mV1200
75DMod mV1500
Signal Error Limits
10

February 2009
1-6 Diagnostics
Setting Error Limits
(cont.)
3. The next prompt asks for the acceleration limit for detecting
erroneous velocity outputs. The E10: ACCELERATION ERROR
message appears if the velocity changes by more than this limit
from one reading to the next.
a. Press [ENTER] to open the text box.
b. Use the numeric keys to enter the acceleration limit.
c. Press [ENTER] to confirm your entry.
Note: In the velocity and acceleration boxes, if the CTF878
currently displays metric measurements, the F1 softkey
displays the word “English.” If it displays English
measurements, the F1 softkey displays “Metric.” Press [F1] to
display the measurement in the alternate format.
4. The last four prompts ask for the minimum and maximum values
in millivolts for the Carrier and DMod categories.
IMPORTANT: Carrier and DMod should be changed from factory
default settings only if absolutely necessary. These
settings may be changed by qualified field service
engineers, only.
To change the Carrier and/or DMod settings:
a. Press [ENTER] to open the text box.
b. Use the numeric keys to enter the desired voltage.
c. Press [ENTER] to confirm your entry.
You have completed entering signal error limits.
•Press [F2] (Cancel) to return to Operate Mode without confirming
the error limits, or
•Press [F3] (OK) to confirm the new limits and return to Operate
Mode.

Diagnostics 1-7
February 2009
The Test Option Within the Service Menu, the Test option includes three tests to
ensure that the CTF878 is performing properly: Test Screen, Test
Keys and Watchdog Test. To enter this option, scroll to the Test entry
on the Service Menu and press [ENTER]. The screen appears similar to
Figure 1-5 below.
Figure 1-5: Test Option under Service Menu
Scroll to the desired entry in the option menu and press [ENTER].
Units Test Diagnostics
Site Program Meter Logging
Signal Setup
Error Limits
Test Keys
Watchdog Test
34
0 50 100
19.25
Service
TAU, ms
Test
Test Screen
Corr SNR

February 2009
1-8 Diagnostics
Testing the Screen To test the proper functioning of the CTF878 screen, scroll to the Test
Screen option in the Test Menu and press [ENTER]. The screen then
shows the message, “Press Any Key To Continue.” Once you press a
key, a screen with a checkerboard pattern appears, as in Figure 1-6
below.
Figure 1-6: A Functioning Test Screen
Pressing a key two more times should result in two more
checkerboard patterns, followed by a series of dark and light screens.
Pressing the key through this sequence should return the CTF878 to
Operate Mode. If the test does not proceed according to this
sequence, please consult the factory.
Press Any Key to Continue

Diagnostics 1-9
February 2009
Testing the Keys The Test Keys option checks the functioning of the various keys on
the keypad. To start the test, scroll to the Test Keys option on the Test
Menu and press [ENTER]. The screen appears similar to Figure 1-7
below. Press any key on the keypad, and a cell representing that key
should darken.
Figure 1-7: The Test Keys Window
Pressing the [F3] key returns the meter to the Operate Mode. If any
key does not appear on the screen, contact the factory.
Exit
7
4
1
5
0
8
2
6
-
9
3
MENU
?
↓
↑
ESC SEL
F1 F2 F3
←→
Test Keys
,

February 2009
1-10 Diagnostics
Testing the Watchdog
Timer Circuit The CTF878 includes a watchdog timer circuit. If a software error
causes the meter to stop responding, this circuit automatically resets
the meter. A properly functioning CTF878 restarts if you run the
Watchdog Test.
To start the Watchdog Test, scroll to the Watchdog Test option in the
Test Menu and press [ENTER]. The screen appears similar to
Figure 1-8 below.
Figure 1-8: Watchdog Test Screen
Press [F2] (No) to cancel the test and return to the Menu screen, or
press [F3] (Yes) to start the test. The CTF878 should go blank for a
few seconds, and then restart. If it does not follow this sequence,
consult the factory.
Units
Site Program Meter Logging
*** WARNING ***
This test should automatically
restart your meter!
Press "Yes" to start the test.
Press "No" to cancel the test.
No Yes
Service
Watchdog Test

Chapter 2

Resetting and Updating
Introduction. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-1
Entering the Service Menu . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-1
Resetting to Factory Default Parameters. . . . . . . . . . . . . . . . . . . . . . . . . . 2-2
Updating CTF878 Software. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-3

Resetting and Updating 2-1
February 2009
Introduction For user convenience, the CTF878 offers a Service Menu. This menu
enables users to perform a variety of functions that they might
occasionally require. Those covered in this chapter include:
•return to factory default parameters
•load updated versions of the meter program into the CTF878
Entering the Service
Menu To enter the Service Menu, press the [MENU] key at the lower right of
the CTF878 keypad. The Menu Bar replaces the Status Bar at the top
of the screen. Press the [X] arrow key to scroll from the Site Menu to
the Service Menu. At the Service Menu, press [ENTER]. The screen
appears similar to Figure 2-1 below.
Figure 2-1: Service Menu
To scroll to a particular option, press the [T] or [S] arrow keys until
you reach the option. Then press [ENTER] to open the option window.
When entering parameters in an option, press:
•the [T] key to step through the available parameters.
•the [S] key to scroll back to a previously entered parameter.
•the [F2] key (Cancel) or the [ESC] key to exit an option at any time
and return to Operate Mode without changing the parameters.
Units Test
Site Program Meter Logging
Signal Setup
Error Limits
Test
Factory Defaults
Flash Update
Calibrate/Test
Test EEProm
34
0 50 100
15.38
Service
Diagnostics
Velocity, m/s
Corr SNR