Ashcroft XLdp - Low Differential Pressure Transmitter - Manual

© 2011 Ashcroft Inc., 250 East Main Street, Stratford, CT 06614, USA • Tel: 203-378-8281, Fax: 203-385-0402 • email: [email protected], www.ashcroft.com.
All specifications subject to change without notice. All sales subject to standard terms and conditions of sale I&M 011-10070 (250-3001) Rev. B 10/11
MODEL XLdp
INSTRUCTION SHEET
Description
The Ashcroft Model XLdp is a low pres-
sure differential pressure transducer to
be used with clean, dry air and other
non-corrosive gases. Both unidi rectional
(e.g. 0/1.0 in. W.C.) and bidire ctional (e.g.
+/– 3.0 in. W.C.) pressure ranges are
offered, as well as a wide selection of
output signals. The storage temperature
limits of the XLdp are from –40 to 180°F.
The unit can operate be tween –20 and
160°F and is temperature compensated
between 35 and 135°F.
A space on the label is provided for
a grease pencil marking. This marking
can identify each unit with a piece of
equipment that it is monitoring. This will
help to avoid tracing the pressure lines.
V min = 12 + (.022A x R
L
)
R
L
= R
S
+ R
W
R
L
= Loop Resistance (ohms)
R
S
= Sense Resistance (ohms)
R
W
= Wire Resistance (ohms)
Loop Resistance ( Ω)
Loop Supply Voltage (VDC)
0 10 12 20 30 36 40
0
250
500
750
1000
1250
OPERATING
REGION
1090 1. GENERAL:
A failure resulting in injury or damage
may be caused by excessive overpres-
sure, excessive vibration or pressure
pulsation, excessive instrument temper-
ature, corrosion of the pressure con-
taining parts, or other misuse. Consult
Ashcroft Inc., Stratford, 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
measuring and containing elements.
3. STATIC ELECTRICAL CHARGES:
Any electrical device may be suscep-
tible to damage when exposed to static
electrical charges. To avoid damage
to the transducer the operator/installer
should follow proper ESD (electrostatic
discharge) protection procedures before
handling the pressure transducer.
WARNING! READ
BEFORE INSTALLATION
m m
Mounting
The unit should be mounted with #8
or #10 screws using the two mount-
ing slots provided. Easy access to the
zero adjustment may be a consideration
when mounting. The transducer can be
mounted in any orientation with virtually
no effect on calibration. Any minor zero
pressure offsets that are encountered
can be adjusted using the zero adjust
potentiometer.
Piping
The two pressure connections are
protected with tubing to avoid debris
entering during installation. It should be
left in place until system tubing is to be
connected. The Ashcroft Model XLdp can
withstand overpressure or vacuum of up
to 15 psi without requiring recalibration.
Recommended flexible tube sizes
should be as follows:
1/4 barb: <
3 ⁄ 16 ˝ ID tube
1/8 barb: < 1 ⁄ 16 ˝ ID tube
Power Requirements
Voltage Output:
The Model XLdp will operate on any
supply voltage from 12-36 VDC (24
VDC typical) drawing less than 5mA.
Current Output:
The voltage required for a 4-20mA out-
put is dependent on the loop resistance
of the circuit. (See figure on electrical
connections.) The Loop Resistance
Chart shows the minimum supply volt-
age (V min ) required for a given Loop
Resistance (R
L
).
CE Options:
Available in 4-20mA output units
using XCE variation. Compliant to
EN61326:1997 Annex A.