Installation Instructions for
Transmission/Gear Pressure SWICHGAGE
®
TP-8318N
Revised 05-99
Section 05
(00-02-0164)
Base Model Description
20P, 25P, A20P and A25P SWICHGAGE
®
The gage pointer makes with an adjustable contact to complete a pilot-duty circuit.
20PE, 25PE, A20PE and A25PE SWICHGAGE
®
Features internal snap-acting SPDT switches, instead of the single pole/pointer
contacts. When the switch closes on falling pressure, it becomes Set, as pres-
sure rises the switch Resets.
20PABS, 25PABS, A20PABS and A25PABS SWICHGAGE
®
Same as 20P, 25P, A20P and A25P with internal SPDT snap-switch for pre-alarm.
Specifications
Case Material
: 20P and 25P Series:
Plated steel.
A20P and A25P Series:
Polycarbonate.
Pressure Connection
: 1/8-27 NPT.
Contact Rating:
Standard is 2A @ 30 VAC/DC resistive (pilot-duty only).
Models 20PE, A20PE, 25PE and A25PE have non-adjustable snap-switch
rated 3A @ 30 VDC inductive, 4A @ 125 VAC inductive.
Warranty
A 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
IMPORTANT Installation
Recommendations
SWICHGAGE
®
Used On Transmission/Clutch Oil Pressure
1.
Install the SWICHGAGE
®
using a Murphy pulsation snubber PD2160 in
the pressure connection at the transmission or gear and at the SWICH-
GAGE
®
. The snubber helps reduce pressure spikes/surges which will
damage the gage sensing element. It also stabilizes the gage readout
through all operating cycles.
Failure to isolate gage in this manner will
void Murphy warranty and possibly cause equipment damage.
2.
Models with pre-alarm have two switch points and when used with Murphy
SS300 speed switch–allows changing between high and low switch points
according to engine RPM. This configuration does away with nuisance
alarms when shifting or when at idle–yet maintains maximum pressure
protection. See Murphy Application Tip AT-01 for further details.
Please read the following information before installing.
A visual inspection of this product for damage during shipping is recommended before mounting.
WARNING
BEFORE 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.
Stainless
Steel Bezel
Polycarbonate
Lens
Adjustable,
Self-Cleaning
Limit Contact
Pulsation
Dampener
(Removable)
Diaphragm
Sensing Element
PD2160
High Pressure Flexible Hose
*
*
NOTE:
A length of flexible hose between the gear and the SWICHGAGE
®
helps dampen pressure surges.
Transmission/Gear
SWICHGAGE
®
CAUTION:
Certain dangers to human safety and to equipment
may occur if some equipment is stopped without pre-warning.
It is recommended that monitored functions be limited to
alarm-only or to alarm before shutdown.
Installation TP-8318N page 1 of 1
CONTROL SYSTEMS & SERVICES DIVISION
P.O. Box 1819; Rosenberg, Texas 77471; USA
+1 281 633 4500
fax
+1 281 633 4588
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 8206336
Villahermosa 52 993 3162117
www.murphymex.com.mx
FRANK W. MURPHY, LTD.
Church Rd.; Laverstock, Salisbury SP1 1QZ; U.K.
+44 1722 410055
fax
+44 1722 410088
www.fwmurphy.co.uk
MURPHY SWITCH OF CALIFORNIA
41343 12th Street West
Palmdale, California 93551-1442; USA
+1 661 272 4700
fax
+1 661 947 7570
www.murphyswitch.com
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 CORPORATION
1620 Hume Highway
Campbellfield, Vic 3061; Australia
+61 3 9358 5555
fax
+61 3 9358 5558
FW Murphy
P.O. Box 470248
Tulsa, Oklahoma 74147 USA
+1 918 317 4100
fax
+1 918 317 4266
www.fwmurphy.com
R
E
G ISTERE
D
USA–ISO 9001:2000 FM 28221
UK–ISO 9001:2000 FM 29422
Printed in U.S.A. 113286N
