Ashcroft T2, G2 Instruction Manual

G2 & T2 PRESSURE TRANSMITTER
INSTRUCTION SHEET

WARNING: READ BEFORE INSTALLATION

Fluid hammer and surges can destroy any pressure transducer and must always
be avoided. A pressure snubber should be installed to eliminate the damaging
hammer 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 damaging 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:

a) Pressure transducer exhibits an output at zero pressure (large zero

offset).
b) Pressure transducer output remains constant regardless of pressure.
c) In severe cases, there will be no output.

WARNING!

A failure resulting in injury or damage may be caused by
excessive overpressure, excessive vibration or pressure pulsation, excessive
instrument temperature, corrosion of the pressure containing parts, or other
misuse. Consult Dresser Instrument, Stratford, Connecticut.

Life Support Policy

Dresser’s products are not authorized
for use as critical components in life
support devices or systems without the
express written approval of the General
Manager, Stratford Operations of
Dresser Instrument, Dresser, Inc. As
used herein:

1. Life support devices or systems are
devices or systems which, (a) are
intended for surgical implant into the
body, or (b) support or sustain life,
and whose failure to perform, when
properly used in accordance with
instructions for use provided in the
labeling, can be reasonably expected
to result in a significant injury to the
user.

2. A critical component is any compo­nent of a life support device or sys­tem whose failure to perform can be
reasonably expected to cause the
failure of the life support device or
system, or to affect its safety or
effectiveness.

WARNING!

Any electrical device may be suscepti­ble to damage when exposed to static
electrical charges. To avoid damage to
the transducer observe the following:

• Ground the body of the transducer
BEFORE

making any electrical connec-

tions.

• When disconnecting, remove the
ground LAST!

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

CAUTION: pressure spikes in excess of the
rated overpressure capability of the trans­ducer may cause irreversible electrical
and/or mechanical damage to the pres­sure measuring and containing elements.

©Ashrcoft Inc. All rights reserved. 250 East Main Street, Stratford, CT 06614 USA
Tel: [phone], FAX [phone] www.ashcroft.com All sales subject to standard terms and conditions of sale. I&M011-10129

GBE 02/06

DESCRIPTION

The Ashcroft Model G2 and T2 pressure
transducers are high performance instru­ments intended for use in industrial appli­cations where the process media is com­patible with the 17-4PH stainless steel
sensor material and the 304 SS process
connection.

MECHANICAL INSTALLATION
Environmental

The G2 and T2 transducers can be stored
and used within the temperature limits of

-40°C to 125°C (-40°F to 257°F). Ingress
protection ratings of the units are depend­ent on the electrical termination specified.
Refer to the wiring diagrams on the reverse
for the IP rating of the unit which is being
installed.

Mounting

The G2 and T2 transducers require no
special mounting hardware and can be
mounted in any orientation with negligible
position error. Although the units can with­stand considerable vibration without dam­age or significant output effects, it is always
good practice to mount the transducer
where there is minimum vibration. For
units with NPT type pressure fittings apply
sealing tape or an equivalent sealant to
the threads before installing. When instal­ling or removing the unit apply a wrench to
the hex wrench flats, located above the pres­sure fitting. DO NOT tighten by using a pipe
wrench on the housing. A 27mm (1

1

⁄16˝)
wrench can be used on the wrench flats of
the hex. For G2 models with detachable
electrical connectors a 6 point deep socket
can also be used to install the unit.

Electro-Magnetic Interference

The circuitry of the G2 and T2 transducers
is designed to minimize the effect of elec­tromagnetic and radio frequency interfer­ence. To minimize susceptibility to noise,
avoid running the termination wiring in a
conduit which contains high current AC
power cables. Where possible avoid run­ning the termination wiring near inductive
equipment.

Field Adjustments

The G2 and T2 transducers are precisely
calibrated and temperature compensated
at the factory to ensure long and stable
performance. There are no field accessible
adjustments on the G2 or T2 transducers.

ELECTRICAL INSTALLATION

Please refer to the reverse of this page for
power supply requirements and for appro­priate wiring protocol based on the partic­ular output signal and electrical termina­tion features of the unit being installed

G2 & T2 PRESSURE TRANSMITTER
INSTRUCTION SHEET

Power Supply Requirements

Output Signal Min Max

Ratiometric* 4.5Vdc 5.5Vdc
(0.5V to 4.5V)
0-5Vdc 9Vdc 36Vdc
1-5Vdc 9Vdc 36Vdc
1-6Vdc 9Vdc 36Vdc
0-10V 14Vdc 36Vdc
4-20mA** 9Vdc 36Vdc

*0.5Vdc-4.5Vdc output is ratiometric to the

nominal 5Vdc supply

**For transmitters with 4-20mA output signal,

the minimum voltage at the terminals is
9Vdc. However, the minimum supply voltage
should be calculated using the adjacent
graph and formula.

Pin #

Voltage 4-20mA

Output Output

1V+ V+
2 Output None
3 Case Gnd. Case Gnd.
4 Common Common

Pin #

Voltage 4-20mA

Output Output

1V+ V+
2 Common Common
3 Output None

GND Case Gnd. Case Gnd.

Pin #

Voltage 4-20mA

Output Output

AV+ V+
B Output None
C Case Gnd. Case Gnd.
D Common Common

Wire Voltage 4-20mA

Color Output Output

Red V+ V+
White Output None
Black Common Common
Green Case Gnd. Case Gnd.
Bare** Drain Wire Drain Wire

©Ashrcoft Inc. All rights reserved. 250 East Main Street, Stratford, CT 06614 USA
Tel: [phone], FAX [phone] www.ashcroft.com All sales subject to standard terms and conditions of sale. I&M011-10129

GBE 02/06

To determine minimum loop supply voltage:

LSV(min)=9(V)+[.022(A)*RL]

Where:

LSV= Loop Supply Voltage (Vdc)
RL= RS+ RW (ohms)

RL= Loop Resistance (ohms)

RS= Sense Resistance (ohms) [Measuring Instrument]

RW= Wiring Resistance (ohms)

10

40

9 (min)

36 (max)

Loop Supply Voltage (Vdc) [LSV]

Power Supply Voltage vs. Loop Resistance

(4-20mA ONLY)

Loop Resistance (R

L

-Ohms)

1400

1200

Shielded Cable, PVC Jacket, 24AWG leads

Wire Color Voltage Output 4-20 mA Output*

Red V+ V+

Black Common V-

White Output V-

Bare** Shield Drain Wire Shield Drain Wire

IP67 Ingress rating

Flying Leads 18AWG

Wire Color Voltage Output 4-20 mA Output*

Red V+ V+

Black Common V-

White Output V-

IP67 Ingress rating

Hirschmann G Series

Mates to Optional Hirschmann G4W1F connector, or equal

Pin # Voltage Output 4-20 mA Output*

1V+ V+

2 Common V-

3 Output V-

4 Case Ground Case Ground

IP65 Ingress rating

3-Pin Delphi (Packard) Metri-Pack 150 series

Mates to Optional Metri-Pack connector 12065287

Pin # Voltage Outputs 4-20 mA Output*

A Common V-

BV+ V+

C Output V-

IP67 Ingress rating

Power Supply Voltage vs Loop Resistance

G2 & T2 ELECTRICAL INSTALLATION

G2 ELECTRICAL TERMINATIONS AND WIRING

T2 ELECTRICAL TERMINATIONS AND WIRING

Wiring Diagrams

Mates to optional Hirschmann connector
Part 933 172-100 or equa

l

Mates to optional Hirschmann connector
GDM 3099 or equa

l

Mates to optional Amphenol Bendix connector
PTO6A-8-4-SR or equal

INGRESS RATING OF THE T2 FOR ALL TERMINATION TYPES IS IP65

* Use either V- termination on G2 with 4-20mA output

** Where shielded wiring is being used; Connect the drain wire to the guard terminal on the read out device or measuring instrument if available. In all other cases connect to the ground of the power supply negative terminal.