Troubleshooting – Badger Meter PVC Tee - 1 1/2 to 4"" User Manual
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Installation & Operation Manual
TROUBLESHOOTING
The Series 200 flow sensors are active devices that are most easily tested at the connection point of the controller to which
they are connected.
The sensor is essentially a 15 Ohm switch with a 600 uA leakage current. With no flow running (the impeller not turning), the
sensor will appear to the controller input as a small current load. When the impeller is turning, it appears a quick series of
5 ms short circuits.
Before trying to troubleshoot, confirm that the flow rates are well above the minimum recommended flow rates. This will
usually purge any air out of the line, and will ensure that the impeller is actually spinning in the flow.
If the controller is not recognizing a flow input from this sensor, test the controller itself by disconnecting the flow sensor, and
very quickly and repeatedly short together the two terminals that the flow sensor was connected to. The controller should
report some flow. If it does not, the problem is in the controller, and not the flow sensor or wiring to it.
If the controller appears to be working, while the sensor is still disconnected measure the open circuit voltage on the
controller's sensor input terminals.
This voltage must be between 8…24V DC for the sensor to operate.
If the voltage is acceptable, reconnect the flow sensor and re-measure. Depending on the age of the flow sensor, the voltage
should drop slightly. Current production sensors will drop about a volt or so, sensors manufactured prior to 2001 will drop to
about 8V DC. If no drop is observed, the sensor is wired backwards, or there is a break in a wire or splice, or the sensor is open
internally. If the voltage drops to near zero, there is either a short in the wiring or splice or the sensor is shorted internally. If
the voltage drops below 7V—but not to levels indicating a short—there is most likely moisture penetration or corrosion in
the wiring or in the sensor itself.
If the electrical tests all look normal, you will have to drain the pipe, remove the sensing element, and spin the impeller
by hand.
When spun by hand, the impeller should spin freely and slide smoothly to a stop, with no evidence of damage or wear on any
of the surfaces, and the controller should recognize the signal and report a flow. If it does not, the sensor electronics are no
longer operational and must be replaced.
If the impeller/bearing is simply worn or damaged, and signal is observed when the impeller is forced to turn, then an
impeller repair kit can be installed as described in "IMPELLER ASSEMBLY AND SHAFT REPLACEMENT" on page 9.
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January 2013