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© 2012 Ashcroft Inc., 250 East Main Street, Stratford, CT 06614, USA. Tel: 203-378-8281 • Fax: 203-378-0499, All specifications are subject to change without notice.  
All sales subject to standard terms and conditions. All rights reserved. www.ashcroft.com.   I&M011-10063-1/01 (250-2924). Rev. A 7/12

1. GENERAL:

A failure resulting in injury or damage may 
be caused by excessive overpressure, 
excessive vibration or pressure pulsation, 
excessive instrument temperature, corro-
sion of the pressure containing parts, or 
other misuse. Consult Ashcroft Inc., Strat-
ford, Connecticut, USA before installing if 
there are any questions or concerns.

2. OVERPRESSURE:

Pressure spikes in excess of the rated 
overpressure capability of the transducer 
may cause irreversible electrical and/or 
mechanical damage to the pressure mea-
suring and containing elements.
Fluid hammer and surges can destroy any 
pressure transducer and must always be 
avoided.  A pressure snubber should be 
installed to eliminate the damaging ham-
mer effects. Fluid hammer occurs when 
a liquid flow is suddenly stopped, as with 
quick closing solenoid valves.  Surges 
occur when flow is suddenly begun, as 
when a pump is turned on at full power or 
a valve is quickly opened.
Liquid surges are particularly damag-
ing to pressure transducers if the pipe 
is originally empty. To avoid damaging 
surges, fluid lines should remain full (if 
possible), pumps should be brought up to 
power slowly, and valves opened slowly. 
To avoid damage from both fluid hammer 
and surges, a surge chamber should be 
installed.
Symptoms of fluid hammer and surge's   
damaging effects:
•  Pressure transducer exhibits an output 

at zero pressure (large zero offset). 

•  Pressure transducer output remains 

constant regardless of pressure

• In severe cases, there will be no output.
FREEZING:
Prohibit freezing of media in pressure 
port. Unit should be drained (mount in 
vertical position with electrical termination 
upward) to prevent possible overpressure 
damage from frozen media.

3. STATIC ELECTRICAL CHARGES:

Any electrical device may be susceptible 
to damage when exposed to static electri-
cal charges. To avoid damage to the trans-
ducer observe the following:
•  Operator/installer should follow proper 

ESD (electrostatic discharge) protection 
procedures before handling the pressure 
transducer.

Note: The shield and drain wire in the 
cable (if supplied) is not connected to the 
transducer body, and is not a suitable 
ground.

MOUNTING 
The transducer requires no special mount ing 
hardware, and can be mounted in any plane 
with negligible position error.
Although the unit can withstand normal  
vibration without damage or significant  
output effects, it is always good practice to 
mount the transducer where there is mini-
mum vibration. 
For units with NPT type pressure fittings 
apply teflon tape or an equivalent sealant to 
the threads before installing.
When tightening, apply a wrench to the hex 
wrench flats located just above the pres-
sure fitting.

 DO NOT tighten by  using a pipe 

wrench on the housing.
POWER SUPPLY – K1 Models Only 
The supply voltage for the 1-5 and 1-6 Vdc 
output transducers must be within the range 
of 10 to 36 Vdc. The maximum  supply volt-
age for a 4-20mA current output transducer 
is 36 Vdc while the minimum supply voltage 
is dependent upon the loop resistance of the 
circuit. The load limitation chart shows the 
minimum supply voltage (V

min

) required for a 

given loop  resistance (R

LOOP

).

NOISE 
For minimum noise susceptibility, avoid 
run ning the transducer’s cable in a con duit 
that contains high current AC power cables. 
Where possible avoid running the cable near 
inductive equipment.
SHIELD WIRING 
Connect the braided shield to the guard 
terminal on the reading instrument (meter, 
etc.) if available or to ground or to the power 
supply negative terminal.

V

min

 = 10V+ (.022A x R

L

)

R

L

 = R

S

 + R

W

R

 = Loop Resistance (ohms)

R

 = Sense Resistance (ohms)

R

 = Wire Resistance (ohms)

1000

750

500

250

0

0

36

20

10

1182

30

 Load Limitations 4-20mA Output Only

(R

 

LOOP 

)

OPERATING 

REGION

WARNING! READ 

BEFORE INSTALLATION

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K1,  K2,  K8
PRESSURE TRANSDUCER 
INSTRUCTION SHEET

ADJUSTMENT POTENTIOMETERS 
The zero and span pots are accessible 
through the top of the case. Loosen the four 
screws and separate the top carefully. The 
zero pot is marked with a white dot. 
VENT TUBE 
The cable will have a clear Teflon vent tube 
that's required at pressure below 500 psi to 
provide atmospheric reference. The open 
end should be placed in a dry area.
OUTPUT – K8 Only 
Sensitivity may be from 6 mV/V to 18 mV/V 
for any individual transducer. Zero offset is 
within ±3 mV/V. Output is proportional to 
supply voltage (ratiometric).
EXCITATION – K8 & K2 
For proper operation a voltage within the 
range of 5 to 10 Vdc must be applied be-
tween the transducer’s supply terminals.

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