Siemens Pacemaker UM344-2 Manual de usuario descargar pdf (Pagina 127)

UM344-2 CALIBRATION AND MAINTENANCE

September 1995

TABLE 6.9 Symptom - Erratic Output

POSSIBLE CAUSE CORRECTIVE ACTION

Loop Wiring Check for 12 Vdc minimum across SIGNAL +/- terminals in transmitter terminal

compartment.

Check power supply output voltage: 17 Vdc minimum; 42 Vdc maximum.

Check for loose loop wiring at power supply terminals, Supply Barriers (if

used), junction boxes, and transmitter terminal compartment.

Check for loose leads at Current Sense Resistor.

Check for accumulation of moisture in transmitter terminal compartment.

Check for multiple grounds on loop cable shield.

Check for the proper type of loop cable and for electrical interference between

the loop cable and any adjacent cables in a cable tray or conduit.

Check signal loop is grounded, not floating. Ground signal loop at one point

only, preferably at the power supply negative terminals.

Loop power supply excessively

noisy

Confirm defective power supply by substituting spare supply for suspect

supply.

Select a higher damping value (software filter time constant).

High level noise pick-up in sensor

leads

Low level leads between sensor and transmitter should be shielded.

Transmitter Electronics Failure Check transmitter STATUS. If a FAILSAFE message is posted, refer to

Section 6.3.2.1, paragraph A, for troubleshooting procedures.

If STATUS is OK, select LOOP OVRD (loop override). Verify loop by setting

output current to 4, 12 and 20 mA (read on Digital Meter or ammeter connected

to TEST +/- terminals). Carefully observe that the selected currents remain

steady.

If current cannot be set or is unstable, replace the Electronics Module. See

Section 6.5.

6.3.3 Diagnosing a Defective Digital (LCD) Meter

The optional LCD is functionally tested during a transmitter power up or master reset. It is also tested

when the MXC TEST program (transmitter self-diagnostics) is executed. The 4 second test activates all

the legends and numerical segments of the LCD. However, if the LCD fails the test, the failure is not

reported by the self-diagnostics. The LCD must be observed when performing the MXC TEST program

to confirm its test.

If the LCD is not functioning correctly, use an on-hand spare LCD to prove the suspect LCD is defective

as follows:

1 2 ... 122 123 124 125 126 127 128 129 130 131 132 ... 182 183

Sin comentarios

Siemens Pacemaker UM344-2 Manual de usuario Pagina 127