14
2551 Blind Magmeter
1
2
3
4
D7
D6
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 fl ow in the pipe.
Blinking Blue:
Normal operation, blink rate is proportional to the fl 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).
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 fl ow from forward fl ow. The output will be the absolute value.
• With Digital (S
3
L) output, reverse fl ow results in 0 fl ow rate displayed on 8900 or with negative numbers on the 9900 and 9950.
• 4-20 mA output can be spanned into negative fl ow range using the USB Confi guration Tool and software.
(Page 7) (example: 4-20 mA = –100 to +100 GPM).
Troubleshooting continued
