00-02-0181
DESCRIPTION
magnetic pick upTRANSCRIPT
MP-8802N page 1 of 2
Magnetic Pickup Installation Instructions Models: MP3298, MP7905, and MP7906
MP-8802NRevised 03-02
Section 20(00-02-0181)
DescriptionA magnetic pickup is an AC generator. It is normally installed into the fly-wheel housing of an internal combustion engine, so that the starter ringgear acts upon it to generate a voltage pulse each time a gear tooth passesthe end of the sensor.
SpecificationsHousing Material:
MP3298: Type 300 Stainless Steel.Locknut: Type 300 Stainless Steel.
MP7905 and MP7906: Type 6061 Aluminum/Anodize Class 1.Locknut: Steel Nickel Plated.
Output Leads (all models): Two insulated leads, 20AWG, STR/TEF insulated per MIL-W-16878D Type E, 1 White and 1 Black.
Output Voltage (all models): 200 V.P.P. TYP. (tested at 1000 I.P.S. 20 Pitch gear, 0.005 Gap., and 100K OHM Load).
Coil Resistance:MP3298: 975 Ohms TYP.MP7905 and MP7906: 2500 Ohms TYP.
Potting (all models): Internal portion of pickup is filled with epoxy resin, making the magnetic pickup oil and moist resistant.
Temperature (all models): -65° to +225°F (-54 ° to 107°C).Coil Induct.:
MP3298: 800 mH max, @ 1K Hz.
MP3298: 400 mH TYP. @ 1K Hz.
Pickup Part Total Threaded ThreadModel Number Length Length Size
MP3298 20700162 3 in. (76 mm) 3 in. (76 mm) 5/8-18 UNFMP7906 20700161 3 in. (76 mm) 3 in. (76 mm) 3/4-16 UNFMP7905 20700160 4-1/2 in. (114 mm) 4-1/2 in. (114 mm) 3/4-16 UNF
Gap Chart
Please read the following information before installing. A visual inspection of this product for damage during shipping is recommended before mounting. These instructions are intended for MP3298, MP7905, and MP7906 models.
WARNINGBEFORE BEGINNING INSTALLATION OF THIS MURPHY PRODUCT
✔ Disconnect all electrical power to the machine.
✔ Make sure the machine cannot operate during installation.
✔ Follow all safety warnings of the machine manufacturer.
✔ Read and follow all installation instructions.
THREADSIZE
5/8-18 UNF
3/4-16 UNF
1/4 1/2 3/4 1
GA
P
.013 in. .028 in. .035 in. .055 in.(0.33 mm) (0.71 mm) (0.88 mm) (1.39 mm)
.015 in. .030 in. .045 in. .062 in.(0.38 mm) (0.76 mm) (1.14 mm) (1.57 mm)
TURN
Typical InstallationMagnetic Pickup Installation (see diagram below) Drill and tap a hole in the flywheel housing (See Specifications for model and thread size). IMPORTANT: Drilling too deep may damagering gear teeth. Blow chips with air hose when drilling and tapping hole.
Gap AdjustmentInsert magnetic pickup and turn until it stops atthe face of the gear. Back-off the gear by turn-ing the pickup counter-clockwise 1/4, 1/2, or3/4 turn (drawing right) .See Gap Chart below to determine gap distancebased on the turn. Check gap clearance byrotating the gear completely around.
NOTE: Magnetic pickup gap should be adjusted sothat the minimum voltage required is attained at the engine’s lowestRPM. The voltage will increase as the speed increases.
If erratic readings occur, remove magnetic pickup and check the magnetic tip for metal chips.
1/4
1/2 3/4
ACMeter
LOADTachSpeedSwitch
AC MeterReading must be taken at load.
After adjusting,set lock-nut.
Drill and tap casing(see thread sizes in Specifications).
Casing
Gear (must be madeof magnetic material).NOTE: Clean gear casing
and magnetic sensor of metal chips or filings.
Gap(see Gap Chart)
Always use a two-conductor shielded cable. Ground theshield to a metal frame ground at the engine end only.
Never run these wiresnext to spark plug wiresor in wire loom with otherwires carrying inductiveloads or alternating current.
GENERAL INFORMATION
MP-8802N page 2 of 2
A. MP3298 and MP7906= 3 in. (76 mm) MP7905= 4.5 in. (114 mm)
Polarity: White lead is positive with respect to Black lead upon approach of ferrous metal.
12 in. (305 mm) min.
0.225 in.(6 mm)
0.1080.104 (3 mm)
BC
A
B. MP3298= 5/8-18 UNF-2A MP7905 and MP7906= 3/4-16 UNF-2A
C. MP3298= 0.250 in. (6 mm) MP7905 and MP7906= 0.370 in. (9 mm)
Wire leads 0.0300.010 (1 mm)
Note: Tested at 1000 I.P.S. 20 pitch gear 0.005 gap and 100K OHM load.
100
100 200 300 400 500 600 700 800 900 1000 Inches per Second (I.P.S.)
90
80
70
60
50
40
30
20
10
0
Vol
tage
Out
put P
eak
to P
eak
Note: Dash indicates not recommended
GearPitch
I.P.S. = R.P.M. x dia. x 3.14
60
% OutputStd. Volts
6
8 10 12
16 20 24 32 48 64 72
187
172 162 157
118 100 85 23 – – –
DIMENSIONS
Output Voltage Operating Chart Gear Pitch/Voltage Output Chart
CONTROL SYSTEMS & SERVICES DIVISIONP.O. Box 1819; Rosenberg, Texas 77471; USA+1 281 633 4500 fax +1 281 633 4588 e-mail [email protected]
MURPHY DE MEXICO, S.A. DE C.V.Blvd. Antonio Rocha Cordero 300, Fracción del Aguaje San Luis Potosí, S.L.P.; México 78384 +52 444 8206264 fax +52 444 8206336Villahermosa Office +52 993 3162117e-mail [email protected]
FRANK W. MURPHY, LTD.Church Rd.; Laverstock, Salisbury SP1 1QZ; U.K.+44 1722 410055 fax +44 1722 410088 e-mail [email protected]
MURPHY SWITCH OF CALIFORNIA41343 12th Street WestPalmdale, California 93551-1442; USA+1 661 272 4700 fax +1 661 947 7570e-mail [email protected]
In order to consistently bring you the highest quality, full featured products, we reserve the right to change our specifications and designs at any time.
MACQUARRIE CORPORATION1620 Hume HighwayCampbellfield, Vic 3061; Australia +61 3 9358 5555 fax +61 3 9358 5558e-mail [email protected] FW Murphy
P.O. Box 470248Tulsa, Oklahoma 74147 USA +1 918 317 4100 fax +1 918 317 4266 e-mail [email protected] www.fwmurphy.com
REGISTERED
USA–ISO 9001:2000 FM 28221UK–ISO 9001:2000 FM 29422
Printed in U.S.A. 078644
WarrantyA limited warranty on materials and workmanship is given with this FW Murphy product.
A copy of the warranty may be viewed or printed by going to www.fwmurphy.com/support/warranty.htm