Baker Hughes Panametrics PanaFlow LC, Руководство пользователя

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4.5 Transducer problems
Ultrasonic transducers are rugged, reliable devices.
However, they are subject to physical damage from
mishandling and chemical attack. The following list of
potential problems is grouped according to transducer
type. Contact Panametrics if you cannot solve a transducer-
related problem.
4.5.1 Transducer problems
• Internal Damage: An ultrasonic transducer consists of
a ceramic crystal bonded to the transducer case. The
bond between the crystal and the case or the crystal
itself may be damaged by extreme mechanical shock
and/or temperature extremes. Also, the internal wiring
can be corroded or shorted if contaminants enter the
transducer housing.
• Physical Damage: Transducers may be physically
damaged by dropping them onto a hard surface or
striking them against another object. The transducer
connector is the most fragile part and is most subject to
damage. Minor damage may be repaired by carefully
bending the connector back into shape. If the connector
can not be repaired, the transducer must be replaced.
IMPORTANT:
Transducers must be replaced in pairs. Refer to Chapter 3,
Programming, to enter the new transducer data into the
meter.
4.6 Service test points
Service tests points can be found on the XMT1000 Main
board just inside the front cover. There are 6 pins found
on the bottom left front side of the main PCB that are
accessible to service personnel. These test points are easily
connected by standard oscilloscope probes and allow the
service person to look at critical signals.
Service Test Points
Figure 81: Service test points
The test points are:
Table 22: Test points
E1 DRTN
E2 Gate
E3 TWIND
E4 RWIND
E5 ARTN
E6 RCV
GATE: Gate connection is input to start and stop flow
calibration process. This input detects an outside source
contact closure. A closure can be programmed to stop
totals or clear totals. Use DRTN along with GATE.
Table 23: Gate connections
TWIND: Transmit Window use DRTN with TWIND
RWIND: Receive Window use DRTN with RWIND
RCV: Receive signal allows the user to look at the receive
signal before it is processed by the meter. It is usually looked
at along with the TWIND and RWIND. Use ARTN with RCV
signal.
4.7 System errors (S-errors)
These errors are from the Flow subsystem. The system errors
have 4 types of information.
1. Indicator
2. Warning
3. Error
4. Fault
The indicator is just a notification to the operator, no
action is needed. The warnings are usually indicative of an
operator error. Errors indicate failures that need attention.
Operator should perform recommended actions to recover
from these errors. Faults are usually indicative of more
serious failures related to background hardware / software
integrity checks performed by XMT1000 meter. See the
table below for error codes, error messages, error type and
recommended actions.
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