TM 5-6115-593-34 NAVFAC P-8-631-34 TO-35C2-3-463-2 undervoltage value. (d) Repeat  steps  (b)  and  (c)  above  to ensure that the specified undervoltage and rated voltage settings are correct. (e) Set    the    oscillograph    chart    speed such   that   the   individual   waveform peaks  are  clearly  visible.    Set  the timing  lines  to  a  minimum  of  0.01 seconds   per   line   or   use   a   60   Hz timing trace.  With the switch open, adjust the trace peak to-peak amplitude to a minimum of one inch (or 25 millimeters). (f) With    the    set    operating    and    the circuit    interrupter    and    the    switch open, read and record both voltmeter readings. (g) Close the switch and circuit interrupter. (h) With     the     oscillograph     recording, open the switch. (i) After allowing sufficient time for the circuit interrupter to operate, check, and    record    the    indication    of    the undervoltage malfunction indicator. (j) Close    the    switch,    and    close    the circuit interrupter. (k) Repeat  steps  (e)  through  (j)  above two additional times. (l) Repeat (a) through (k) for the other undervoltage value specified in paragraph 16-1. e. Results. (1) From the oscillograms made in paragraph 16-20c  determine  and  tabulate  the  time between the application of the overvoltage  and  operation  of  the  circuit interrupter for each application of overvoltage. (2) From the oscillograms made in paragraph 16-20d  determine  and  tabulate  the  time between the application of the undervoltage   and   the   operation   of   the circuit  interrupter  for  each  application  Of undervoltage. (3) Compare these results with the requirements of table 16-1. 16-21.    LOW  OIL  PRESSURE  PROTECTIVE  DEVICE TEST. a. General.          Since    generator    sets    frequently operate unattended for long periods, the engine is  equipped  with  a  low  oil  pressure  protective device.      This   device   shuts   down   the   engine when the oil pressure drops below the safe limit. b. Apparatus.    The  following  equipment  shall  be required to perform this test: (1) Oil pressure gauge (±1 percent) (2) Flexible oil line (or copper tubing). (3) Regulating valves (4) Brass fittings. c. Procedure. (1) Preparation     for     test.          With     set     not operating   remove   the   protective   device tap  from  the  engine  block  and  reconnect as    shown    in    figure    515.1-I    with    the protective  device  and  oil  pressure  gauge in    approximately    the    same    horizontal plane as the protective device tap located on the engine. 16-18