Ametek Drexelbrook 505-1320 Series, Инструкция по установке и эксплуатации

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505-1320 Series Ultrasonic Open Channel Flowmeter
TM
SECTION 5
TROUBLESHOOTING
5.3 Troubleshooting
Procedures
5.2 Checking
Transducer
5.3 Checking
Temperature
Sensor
The 505-1302 instrument is designed to give years of unat-
tended service. No periodic or scheduled maintenance is
required.
If a problem should occur with the operation of the transmit-
ter, use the following procedure for troubleshooting.
a. Ensure wiring connections are correct.
b. If the liquid surface has severe turbulence in the area
where the ultrasonic beam hits, a stilling well
installation may be required. Consult factory.
c. Any continuous ultrasonic transmitter signal/echo will
be adversely affected by significant foam on the liquid
level surface. If this condition exists, please consult the
factory for further application review.
d. Ensure that the transducer face is not recessed into a
mounting nozzle. Spurious reflections from the
nozzle openings into the vessel can cause faulty
operation.
e. If attempts to locate the difficulty fail, notify the local
factory representative, or call the factory toll-free at
1-800-527-6297. To aid in troubleshooting, please
complete the information on
Table 5-1 before calling
the factory service department.
An ohmmeter test is used to check the transducer crystal. It
can also be used to verify that the wires from the transducer
to the sensor (on a remote system) are not reversed, shorted,
or open.
Using a digital ohmmeter, a reading of 9-13K ohms should be
present between Center Wire [CW] to Shield [SHD].
—Resistance Check
a. Disconnect the temperature transducer wires (brown
and orange) leading to the transducer.
b. Using a digital ohmmeter, a good transducer measures
12 to 35 megohms with the positive test lead on the
orange lead and the negative test lead on the brown
lead (standard sensor). The negative test lead
attaches to the brown and white striped wire on the
high temperature sensor (703-6-1).
c. Reverse the meter leads and an open circuit (infinite
ohms) should be observed.