MTD 464 Betriebsanleitung PDF herunterladen (Seite 395)

ARMY TM 9-6115-464-34

AIR FORCE TO 35C2-3-445-2

NAVY NAVFAC P-8-624-34

(2) Calculate the short-circuit current using the peak-to-peak amplitudes of the current trace and the

steady state ammeter reading prior to application of the short circuit. See figure 512.1-11.

(3) Tabulate the above results and the malfunction indicator indication for each line connection at each

voltage connection and compare the results with the requirement in table 4-1.

4-18. CIRCUIT INTERRUPTER TEST (OVERLOAD CURRENT)

a. General. A circuit interrupter is connected between the generator voltage reconnection system and the

generator output terminals to disconnect the generator output from the load and to protect the generator from a

sustained overload current. The circuit interrupter is operated from a current sensor external to the interrupter.

b. Apparatus.

Instrumentation for measuring load conditions and field voltage and current shall be as

described and illustrated in MIL-HDBK-705. In addition, a stopwatch or an oscillograph with galvanometers

matching network and a non-inductive shunt as described and illustrated in MIL-HDBK-705, Method 106.1,

paragraph 106.1.3 and galvanometers having a flat frequency respond (within plus or minus 5%) from dc to

3000 Hz.

c. Procedure.

(1) Preparation for test. Connect the load and field instrumentation in accordance with the applicable

figure of MIL–HDBK–705, Method 205.1, paragraph 205.1.10 for one voltage and frequency.

CAUTION

(a)

(b)

(c)

(d)

If the circuit interrupter fails to operate within the time specified in table 4-1 at any time

during the performance of this method, manually open the circuit interrupter and

reduce the load impedance to rated value before reclosing the circuit interrupter.

Record on the data sheet the failure of the interrupter to operate and the total elapsed

time the overload was on the set. Failure to observe this caution could result in

damage to the equipment

Start and operate the generator set at rated voltage, rated frequency and rated load.

Allow the generator set to stabilize at rated load, voltage and frequency. During this period,

readings of the load and field instrumentation shall be recorded at minimum intervals of 10 minutes.

If necessary, adjustments to the load, voltage and frequency maybe made to maintain rated load at

rated voltage and frequency. Adjustment to the load, voltage or frequency shall be noted on the

data sheet. Stabilization will be considered to have occurred when four consecutive voltage and

current readings of the exciter field either remain unchanged or have only minor variations about an

equilibrium condition with no evident continued increase or decrease in value after the last load,

voltage or frequency adjustment has been made.

In one step, increase the load current to the overload current value specified in table 4-1 (the

increase in current may be accomplished by any practical means, e. g. reactively or using reduced

voltage levels).

NOTE

The frequency shall be maintained at rated conditions, the load current shall be kept

constant and the load current shall be balanced equally among the phases.

Simultaneously with the load current increase, start the stop watch.

Record all load instrumentation and the time, in seconds, required for the circuit interrupter to

operate.

4-18

1 2 ... 390 391 392 393 394 395 396 397 398 399 400 ... 492 493

Kommentare zu diesen Handbüchern

Keine Kommentare

MTD 464 Betriebsanleitung Seite 395

Kommentare zu diesen Handbüchern

Verwandte Produkte und Handbücher für Gartenschredder MTD 464