ABB K-TEK AccuTrak AT500, Installation & Operation Manual

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AT500-0200-1b (10-2010) DCN0528 7
3. TROUBLESHOOTING INFORMATION
3.1 Proper Power-Up
Use a mA meter to measure the output current (see section 2.2 for mA monitor connections). When power is applied, the output
should go to 4.00 mA for at least 1 second, and then to either the measured level or an alarm condition output. If this does not
happen, the transmitter may not be receiving enough power, or the main electronic is defective. Excessive current above 21 mA
is also an indication of improper power-up or defective electronics.

Valid Current Loop Outputs:
-21.0 mA If HI ALARM was selected, a loss of signal, no float detected, problem with the configuration, or a malfunction,
will cause the output to be set to the alarm condition of 21.0 mA.
-
20.6 mA OVERRANGE: When the level increases above the 20 mA point, the output will continue up to 20.6 mA and
then latch at that value, until the level comes back down again.
-
3.8 mA - 20.6 mA Normal output range
-
3.8 mA UNDERRANGE: When the level increases below the 4 mA point, the output will continue down to 3.8 mA and
then latch at that value, until the level comes back up again.
-
3.6 mA If LOW ALARM was selected, a loss of signal, no float detected, problem with the configuration, or a malfunc-
tion, will cause the output to be set to the alarm condition of 3.6 mA.
3.2 Output Stability
If the current output occasionally jumps up or down but not to an alarm condition:
This can be an indication of noise or grounding problem. Field wiring should be run with an individually shielded cable. Insure
that the transmitter housing is effectively connected to earth ground.
There may be a location on the tube that has retained some magnetization, and needs to be cleared. This can happen if a mag-
net or float was used to manually calibrate the sensor and if it was pulled away at 90 degrees from the tube. To avoid this, al-
ways slide the magnet parallel to the tube and remove it by going past either end of the tube. To clear any remaining magnetiza-
tion, slide a magnet or float against and parallel to the tube, from one end to the other.
3.3 Conversion from AT500 to AT600 or AT600 to AT500
It is possible to convert a bottom connected AT600 to an AT500 by adding a float and other parts. It is also possible to convert an
AT500 to a bottom connected AT600 by adding mounting clips. Please consult the factory.
It is not possible to convert a top connected AT600 to an AT500 or vice versa. If you wish to make this change, the transmitters
will have to be replaced.