GF Signet 2551 Magmeter Flow Sensor - Blind - Manual (Page 11)

11 2551 Magmeter
11.2 Troubleshooting
11. Maintenance
The 2551 Magmeter requires very little maintenance. There are no user-serviceable components in the Magmeter.
• If the À uid contains deposits and solids that may coat the electrodes, a regular cleaning schedule is recommended.
• Do not use abrasive materials on the metal electrodes. Clean with soft cloth and mild detergent only.
• Use a cotton swab and mild detergent to remove deposits on the metal electrodes at the tip of the sensor.
11.1 Environmental Recommendations:
• When used properly, this product presents no inherent danger to the environment.
• Please follow local ordinances when disposing of this or any product with electronic components.
11.3 Troubleshooting with the RED and BLUE LEDs
Both Off:
The power is off or the sensor is not connected.
Solid Blue: The power is on, the pipe is full, but there is no À ow in the pipe.
Blinking Blue: Normal operation, blink rate is proportional to the À ow rate.
Alternating Red-Blue: Empty pipe indication (electrodes are not wet).
Blinking Red: System errors (electrical noise interference).
Solid Red: Instrument error (defective electronics component).
1
2
3
4
D7
D6
Flow Flow
If the 2551 detects an empty pipe:
• Frequency output will be locked to 0 Hz if electrodes are not wet.
• Digital (S
3 L) output will be locked to 0 if electrodes are not wet.
• 4 to 20 mA will be locked to 4 mA if electrodes are not wet.
• Blue and red LEDs will blink alternately if electrodes are not wet.
If the 2551 detects REVERSE FLOW:
• Frequency out cannot distinguish reverse À ow from forward À ow. The output will be the absolute value.
• With Digital (S
3 L) output, reverse À ow results in 0 À ow rate displayed on 8900 or with negative numbers on the 9900.
• 4-20 mA output can be spanned into negative À ow range using the 3-0250 USB Setup Tool and software. (See section 9)
(example: 4-20 mA = –100 to +100 GPM).
Symptom Possible Cause Solution
Output is erratic and unstable.
Magmeter installed too close to upstream
obstruction.
Relocate the magmeter to have straight
uninterrupted pipe upstream of the sensor for
at least 10 x the pipe diameter.
Magmeter located in area exposed to air
bubbles/pockets.
Eliminate air bubbles in the pipe.
Magmeter is installed in pipe backwards.
Remove the magmeter and reinstall with the
À ow direction arrow on the sensor body pointed
DOWNSTREAM.
Electrical noise is interfering with the
measurement.
Review the grounding of the magmeter and the
pipe. Install adequate Earth ground to allow the
Magmeter to operate properly.
Electrodes are coated with solids.
Carefully clean the electrodes. Refer to sensor
manual for details.
New sensor; metal surface not properly
conditioned.
Soak sensor overnight in À uid.
Output is not 0 when À ow is stopped.
Electrodes not adequately conditioned. Soak sensor overnight in À uid.
Vibration or other movement in pipe causes
magmeter to detect À ow.
Increase the Low Flow Cutoff.
Electrical noise interference.
Modify grounding to protect the Magmeter from
interference.
Defective Magmeter. Return to factory for service.
4-20 mA current output is incorrect.
Loop device not scaled same as Magmeter.
Use 3-0250 Setup tool to respan the Magmeter
to match Loop device.
Respan Loop device to match Magmeter.
Range Jumper not placed correctly. Set Range Jumper correctly.
Defective Magmeter. Return to factory for service
Frequency output is inoperative
Digital (S
3 L) output is inoperative.
Loop output is inoperative.
2551 is wrong model. Frequency/S 3 L model: 3-2551-11
Blue jumper not in correct position. Place blue jumper correctly. (Sec. 5 pg. 4)
Wiring is not correct. Check wiring, make corrections.
Frequency input to other manufacturer's À ow
instrument does not have pull-up resistor.
Install 10 kŸ resistor. (section 8.1, pg. 6)
Output is 22.1 mA
Conductivity is less than 20 —S/cm (the À uid
is too clean for Magmeter).
Unsuitable application for Magmeter.
Electronic component failure. Return 2551 to factory.