SPECIAL APPLICATION SWICHGAGES": ABS, EO, DP, VWC, ST ALARM BEFORE SHUT-DOWN TWO SWITCH OPTION ABS:  SWICHGAGEâ  with Alarm Before Shut-down The  ABS  has  a  standard,  front  limit-contact  for  low  pressure equipment shut-down and an internal, SPDT micro switch for Alarm Before Shut-Down (see Wiring Diagram).  When the low side   of   the   micro   switch   SETS   (preset   point,   on   falling pressure),  the  NC  side  of  the  switch  completes  a  circuit  to activate an alarm.  From this point the pressure must increase approximately   10%   of   scale   before   the   micro   switch   will RESET  and  open  the  circuit;  if  pressure  falls,  the  shut-down circuit will be completed. NOTE:  The  front  contact  shut-down  limit setting (adjustable) and micro switch low point are preset at the factory; if settings other  than  standard  are  necessary,  then specify when ordering. FILTER DIFFERENTIAL PRESSURE DP:  Differential Pressure SWICHGAGE Installation:  1) connect the input side of the filter to the center port:  2) connect the filter output pressure to the upper port - CAUTION:   use   a   7/16"   wrench   on   the upper    port's    wrench    flats    to    prevent damage   to   the   gauge.      DO   NOT   over tighten  port  connections;  3)  set  the  limit contact to the manufacturer's filter specifications:  4) connect wiring to alarm and/or shutdown devices. DRY AIR CLEANER RESTRICTION VWC:  Water Column Calibrated, Vacuum SWICHGAGE Installation:  1) mount the VWC away from engine vibration; 2) run the vacuum line from the gauge to a point between the air cleaner    and    (a)    carburetor    on    carbureted    engine,    (b) turbocharger   on   turbocharged   diesels,   (c)   the   engine   on naturally   aspirated   diesels.      NOTE:      a   flexible   section   is essential   at   some   point   in   the   vacuum   line   to   eliminate vibration.  Be sure the SWICHGAGE is grounded in a 12 or 24 volt system, and that the alarm used Is of the same voltage as the battery. MICRO-SWITCH! LIMIT CONTROL EO:  SNAP-ACTION Pressure SWICHGAGE An EO is the combination of a MURPHYGAGEâ  and a SPDT micro switch.  The switch will SET (see wiring Diagram) at its preset low pressure point on falling pressure.  As the pressure rises, the switch will  RESET,  approximately  10%  of  scale  above  the  low  pressure SET   point.      (The   10%   difference   is   inherent   in   the   physical movement of the micro switch.) By knowing the low pressure SET point,  this  3  wire  SWICHGAGE  can  be  used  to  make  or  break  a circuit. For Example, you have a 0-100 psi EO with a SET point of 15 psi: the switch will RESET at +10% of scale or 25 psi.  This EO could be wired to light a lamp on low pressure start-up, and then put out the lamp as pressure rises past 25 psi. The SPDT micro switch is rated 3 A @ 30 VDC inductive and 4 A @ 125 VAC inductive. FLASHING LED ALARM ST:  LED Flashes On SWICHGAGE'' Closure The ST has a standard, front limit-contact for low pressure alarm.  For shut-down or auxiliary alarm, wire to compatible rating, see examples of Murphy audible alarm and magnetic switches given below. TROUBLE SHOOTING TIPS (Where problem appears to involve Murphy products) PROBLEM PROBABLE CAUSE & POSSIBLE CORRECTION Engine will not start Blown fuse in magnetic switch circuit: replace with 14 A fuse. False ground in control circuit: repair. Open circuit (Fault Sensitive): repair. Control circuit overloaded by accessories: reroute accessories. False Shut-down Intermittent shorting in wiring due to wear or insulation breakdown check all wiring, replace as necessary. Fault Sensitive circuit has intermittent open or short: check all wiring, replace as needed. Vibration causes the magnetic switch to trip: repair, replace or relocate switch as needed. SWICHGAGE closes but does not trip Incomplete circuit: locate open circuit and repair. the magnetic switch or kill the engine. Magneto not providing power to primary terminal post: repair magneto. C.D.  type magnetic switch being used with magneto or battery: replace with correct switch. SWICHGAGE closes and kills engine. Defective magnetic switch binds outside, prevents trip: adjust or but does not trip the magnetic switch replace the switch. Conventional magnetic switch is used with C.D.  ignition: replace with a C.D.  designated switch. TATTLETALE tripped but engine Lost ground to kill engine: repair. still running (mag.  or C.D.). Clogged lines or pulsation dampener: remove and clean or Pointer will not operate properly. replace. inaccurate readings. Kinked/crimped/broken pressure or vacuum line: replace line. Pointer or contact burned in two Without exception this Is caused by incorrect wiring or a short circuit: refer to wiring diagrams and recheck wiring: replace SWICHGAGE'. If you need additional assistance, contact YOUR LOCAL MURPHY DEALER, or a Murphy representative at one of the offices listed on this form.