Dwyer HADP User Manual

Bulletin P-HADP

Series HADP High Accuracy Differential Pressure Transmitter

Specifications - Installation and Operating Instructions

4x 6-32UNC-2B
7/64 [2.78] MIN FULL THRD

1-3/32

2-3/32

[53.18]

33/64
[13.1]

[26.99]

1-1/16

[26.99]

5/8

[15.88]

1-1/16

3/16

[4.76]

1/8-27

NPT PORT

5/16

[7.94]

[27.78]

2

[50.8]

CABLE

2´ LONG

5/16

[7.94]

1-1/2

[38.1]

[22.23]

1/8

[3.18]

1/8

[3.18]

7/8

4x Ø5/32 [Ø3.97]

MOUNTING HOLES

Ø2-47/64

[69.45]

3

[76.2]

3-1/4

[82.55]

The Series HADP transmitter has been carefully calibrated before shipment
to you, and it should be handled with the same care given any precision
instrument. Pressure range and dimensions are reported on the applicable
specifications bulletin.

Ambient Conditions

Do not submerge in liquids, use in ambient conditions corrosive to
anodized aluminum, subject to spray or dripping, or use in a high
vibration environment. The transmitter is very slightly sensitive to
acceleration in the pressure fitting axis. Installation is recommended in
the vertical position, with the pressure port downward. This position
minimizes damage from drippage of pressure system piping.

Installation of Pressure Fittings

Your transmitter is designed for most accurate operation when
subjected to pressures within the designated pressure range. Refer to
the specifications for proof pressure limits. Subjection to excessive
pressure voids the warranty. Do not overpressure.

Standard sealants such as pipe tape generally are satisfactory. For the
most sensitive pressure ranges, excessive high torquing of a metal
pressure fitting may cause slight zero shift which may be trimmed out
using the zero adjustment. Use of a plastic fitting often shows no
noticeable zero shift. The torquing effect does not appreciably affect
linearity or sensitivity. The wrench flat on the Series HADP should be
used when installing the positive pressure fitting.

SPECIFICATIONS
Service: Compatible non-conducting

air/gas.

Wetted Parts:

Positive (high) Pressure Port:
Gases compatible with SS, hard
anodized 6061 aluminum (Buna-N
O-ring);
Reference (low) Pressure Port:
Anodized aluminum, alumina
ceramics, gold, fluorocarbon
elastomer sealant & Buna-N O-ring.

Accuracy: <±0.14% FS.
Stability: <±0.1% FS over 6 months @

70°F (21°C).

Pressure Limits: See Model Chart.
Temperature Limits:

Operating: 0 to 175°F
(-18 to 71°C);
Storage: -65 to 250°F
(-53 to 121°C).

Compensated Temperature Range:

30 to 150°F (-1 to 65°C).

Thermal Effect: <±1.0% FS / 100°F.
Power Requirements: 17 to 42 VDC.
Output Signal: 4 to 20 mA for current

models, 0 to 5 VDC for voltage models.

Zero and Span Output:

Zero output: Factory set to within

±0.07 mA;
Span (FS) output: Factory set to
within ±0.07 mA.

Loop Resistance:

Minimum supply voltage (VDC) = 17
+ 0.02 x Resistance of receiver plus
line;
Maximum supply voltage (VDC) =
42 + 0.004 x Resistance of receiver
plus line.

Zero and Span Adjustments: None.
Response Time: <5 msec.
Current Consumption: <30 mA.
Electrical Connections: 2 ft multi-

conductor cable.
Process Connections: 1/8˝-27 NPT
internal (both positive and negative
ports).
Mounting Orientation: Pressure port
90° parallel to ground.
Thermal Effects: Max. zero: ±1.0
(±1.8); %FS / 100°F (100°C) max.

Weight: 8 oz (227 g).
Agency Approval: CE.

DWYER INSTRUMENTS, INC.

Phone: [phone] www.dwyer-inst.com

P.O. BOX 373 • MICHIGAN CITY, INDIANA 46361, U.S.A. Fax: [phone] e-mail: [e-mail]

A. Positive Pressure Fitting and Media Compatibility

PRESSURE

TRANSMITTER

POWER SUPPLY

RECEIVER

+

–

+ –

Series HADP: 1/8˝-27 NPT internal fitting

For use with gases compatible with stainless
steel, hard anodized 6061 aluminum, Buna N
“O” ring.

B. Reference Pressure Fitting and Media Compatibility (Differential
pressure measurements only.)

Notes:

(1) Differential pressure models can be used to measure gage pressure

by leaving the reference port open to atmosphere.

(2) Line Pressure refers to pressure applied to both high and low sides

of the sensing device simultaneously. Refer to the product data sheet
to determine maximum differential pressure and overpressure limits.

Electrical Information for Standard 24 VDC Excitation Pressure
Transmitters (nominal)
Connections

Cable Lead Function
White Positive Excitation
Yellow Positive Output
Brown Negative Output
Black Negative Excitation - (to circuit ground)
Case Shield

Electrical

The electrical circuit is equivalent to a 4 terminal network, which can be
grounded at only one point, either at the negative excitation or the negative
signal output lead, but must not be commoned or grounded at more than
one point.

The pressure transmitter must be operated with the case connected either
to the negative excitation terminal or to the negative output terminal.
Failure to do this may result in damage to or unsatisfactory operation of the
unit. This connection may be made by connecting shield and black
(negative excitation) leads or alternately by connecting the shield and
brown (negative output) leads together. Best shielding against noise will be
obtained by connecting the shield and negative excitation (black) leads.

Electrical

Operation is from a ±24 VDC supply (common return grounded), and
provides you with the negative signal output lead also at the common
ground potential. Thus many transmitters can be operated from one power
supply into single-ended loads. Circuit is reversed voltage protected for at
least 5 minutes. Internal transient suppression network is provided for short
duration transients to 150 volts.

Grounding

For general usage and best results (lowest noise) grounding of the
shield/case to the black lead is recommended.

Power Supply Advice

This transmitter has been designed to operate from a ±24 VDC source.
The ±24 V is 24 V above the common power return-lead, and the -24 V is
24 V below the common power return lead.

All three power leads must be connected. The transmitter will not function
if just the +24 V and -24 V leads are connected to the power source.

To avoid circuit damage due to excessive voltage, the positive supply
voltage should be held within the range of +15 V to +20 V (+22 V to +30
V), and the negative supply voltage should be held within the range of -10
V to -20 V (-10 V to -24 V).

Electrical Information for 4 to 20 mA Pressure Transmitter

Electrical

The circuit is designed to operate as a true 2-wire 4 to 20 mA pressure
transmitter.

Connection

The transmitter has two electrical leads. These may be connected for
current flow in either direction, without change in performance or damage.
We suggest that the electrical cable shield be connected to the system loop
circuit’s ground, thereby improving electrical noise rejection.

Wiring 4 to 20 mA Output

The circuit has internal protection:
Reversed excitation voltage for at least 5 minutes.
Short-circuit or signal output leads.
Short duration power line transients up to 150 volts.

Note on long cable use:
In some instances, use of long cables (several hundred feet length) may
introduce enough cable capacitance into the circuit to cause output
oscillations. If encountered, this oscillation may be eliminated by
connecting a 100 ohm resistor (1/8th watt or larger) in series to each of the
output leads at the end of the 2 ft transmitter cable. These series resistors,
of course, add to the output resistance.

Wiring 0 to 5 VDC Output