Murphy Swichgage 45 Series User Manual
45 series pressure swichgage
45-96003B page 1 of 2
■
Combination Pressure Swichgage instru-
ment and Built-in Electromagnetic Switch
■
High and Low Contacts Can Disable
Engine’s Ignition Due to Critical Pressure
■
Magnetic Switch Will Not Allow Engine
Restart Due to Flywheel Inertia
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Semi-Automatic Low Pressure Override
Push Button for Engine Startup
Description
The 45 Series pressure Swichgage instrument
incorporates a built-in electromagnetic switch
to disable an ignition whenever the gage con-
tacts operate.
Flywheel inertia cannot restart the engine since
the electromagnetic switch will not allow the
ignition to operate until manually reset.
A semi-automatic lockout push button over-
rides the low pressure contact for equipment
startup. The lockout automatically disengages
when pressure is established allowing the low
limit contact to be armed for operation should a
low pressure condition occur.
Models are available for conventional magnetos,
capacitor discharge (CD) ignitions, 12/32 VDC
battery systems, and 120 VAC power sources.
Ranges are available from 30”vac (-101 kPa)
[-1.01 bar] thru 10,000 psi (138 MPa) [1379 bar].
Applications
Recommended instrument for most field gath-
ering pumps, the 45 Series instantly stops your
pump when pressures drop due to line breaks,
leaks or when your tank is pumped out.
Overpressure shutdown can occur due to clo-
sure of valves in the line, or other line
restrictions.
Specifications
Dial: White on black, dual scale, psi and kPa
standard, 4-1/2 in. (114 mm) diameter.
Case: Die cast aluminum.
Process Connection:
1/4 NPT thru 1000 psi (6.9 MPa) [69 bar];
1/2 NPT 1500 psi (10 MPa) [103 bar] thru
10,000 psi (138 MPa) [1379 bar].
Overrange: Do not exceed 10% above full range.
Sensing Element: Select from bronze or 316 stain-
less steel bourdon tube.
Gage Accuracy: ±2% for first and last quarters of
scale; the middle half is ±1%.
Pressure Relief Disc: Located in rear of case.
Contact Ratings:
45B = 12/30 VDC coil; 10 A, 32 VD DC contacts
45CD = CD ignition coil; 10 A contacts
45M = Magneto ign. coil; 10 A contacts
45N = 120 VAC coil; 10 A, 120 VAC contacts
Wire Connections:
1/2 NPT conduit and terminal block.
Item Weight:
5 lbs 9 oz (2.5 kg) approximately.
Item Dimensions:
10 x 9 x 6 in. (254 x 229 x 152 mm).
Basic Models
45B Series Swichgage instrument
For use with 12-32 VDC battery ignition systems;
it includes battery ignition type magnetic switch.
45CD Series Swichgage instrument
For use with (CD) capacitor discharge ignitions;
it includes CD ignition type magnetic switch.
45M Series Swichgage instrument
For use with magneto type ignitions; it includes
magneto ignition type magnetic switch.
45N Series Swichgage instrument
For specific use with 110 VAC Power Sources;
it includes 120 VAC type magnetic switch.
8-7/16 in.
(214 mm)
3-3/8 in.
(86 mm)
1/2 NPT
conduit
Dimensions
45-96003B
Revised 07-06
Catalog Section 05
45 Series Pressure Swichgage
®
instrument
To Disable Magneto, CD and Battery Ignition Systems