Siemens Pacemaker UM344-2 Uživatelský manuál stáhnout pdf (Strana 126)

CALIBRATION AND MAINTENANCE UM344-2

September 1995

TABLE 6.7 Symptom - Output Current Fixed Below Scale

at Approximately 3.84 mA

POSSIBLE CAUSE CORRECTIVE ACTION

Loop supply voltage less than 12 Vdc at transmitter

SIGNAL +/- terminals.

Replace power supply.

Thermocouple Burnout (if Downscale protection) or

thermocouple extension wire(s) open.

Refer to Figure 4-13 and perform a standard open circuit

(thermocouple) check between transmitter terminals #1

and #3.

Thermocouple wires have polarity reversed. Consult thermocouple wire tables (or Table 6.1) and

determine color code for positive and negative wires.

Check wire connections at transmitter terminal

compartment and at thermocouple head if thermocouple

is remote mounted.

Shorted thermocouple extension wires (due to insulation

failure) between remote mounted thermocouple and

transmitter.

The transmitter will read the temperature at the short

(junction) which, if 3% less than the configured Zero

range value, will force the output current to a maximum

low value of 3.84 mA.

Special Time-Domain Reflectometer (TDR) measurements

can be used to locate the short; otherwise, a visual

inspection of the length of wire must be made to locate

the short.

Incorrect lead connections on 3-wire RTD. Refer to Figure 4-13 and check for correct sensor wiring.

Open RTD lead on double-lead side of 3-wire RTD. Refer to Figure 4-13 and perform continuity check

between RTD wires connected to transmitter terminals #1

and #2 to confirm open circuit.

The single side RTD lead is shorted to one of the double-

side RTD leads (RTD shorted out).

Refer to Figure 4-13 and perform continuity check

between RTD wires #1 and #3 to confirm shorted RTD

Temperature is less than Lower Range Limit (LRL). Re-range transmitter. Refer to Section 5.

TABLE 6.8 Symptom - Output Current Fixed Above Scale

at Approximately 21.8 mA

POSSIBLE CAUSE CORRECTIVE ACTION

Thermocouple Burnout (if Upscale protection) or

thermocouple extension wire(s) open.

Refer to Figure 4-13 and perform burnout check on

thermocouple and continuity check on wires

between transmitter terminals #1 and #3 to isolate

the fault.

RTD element open or, if RTD is remote mounted,

return wire to transmitter terminal #3 is open

Refer to Figure 4-13 and perform continuity checks

on RTD and RTD return wire to transmitter

terminal #3 to isolate the fault

Temperature is greater than Upper Range Limit

(URL).

Re-range transmitter. Refer to Section 5.

1 2 ... 121 122 123 124 125 126 127 128 129 130 131 ... 182 183

Komentáře k této Příručce

Žádné komentáře

Siemens Pacemaker UM344-2 Uživatelský manuál Strana 126

Komentáře k této Příručce

Související produkty a manuály pro Měření, testování a kontrola Siemens Pacemaker UM344-2