MAMAC SYSTEMS PR-274, PR-275 Technical Information

8189 Century Boulevard • Minneapolis, MN 55317-8002 • USA

800-843-5116 • 952-556-4900 • Fax [phone]

[e-mail] • www.mamacsys.com

For Additional Information See PR-274/275 Data Sheet

SPECIFICATIONS

Accuracy*: ±1% FS

Overpressure: 10 PSID

Supply Voltage: 12-40 VDC

12-35 VAC (VDC output units only)

Supply Current: VDC Units - 10 mA max.

mA Units - 20 mA max.

Enclosure: 18 Ga C. R. Steel NEMA 4 (IP-65) or Panel Mount Chassis

Finish: Baked on enamel-PMS2GR88B

EMC Conformance: EN 55022, 55024, 61000-3-3,

61000-4-2, 3, 4, 5, 6 & 11

Compensated Temp Range: 25°F-150°F (-4°C-65°C)

T. C. Error: ±0.0125%/°F (.02%/°C)

Operating Temp Range: 0°F-175°F (-18°C-80°C)

Media Compatibility: Clean dry air or any inert gas

Environmental: 10-90%RH Non-Condensing

Termination: Unpluggable screw terminal block

Wire Size: 12 Ga max.

Load Impedance: 1.6K ohms max. at 40 VDC (mA output units)

1K ohms min. (VDC output units)

Weight: Enclosure - 1.0 lbs. (.45 kg)
Panel Mount - 0.5 lbs. (.25 kg)

ORDERING INFORMATION

PACKAGING RANGE OUTPUT

274 (enclosure)

275 (panel mount)

R1

0 TO 0.10 / -0.05 TO +0.05

("wc)

R2

0 TO 1.0 / 0 TO 0.5 / 0 TO 0.25 /

("wc)

-0.5 TO +0.5 / -0.25 TO +0.25 /

-0.125 TO +0.125

R3

0 TO 5.0 / 0 TO 2.5 / 0 TO 1.25 /

("wc)

-2.5 TO +2.5 / -1.25 TO +1.25 /

-0.625 TO +0.625

0 TO 30 / 0 TO 15 / 0 TO 7.5 /

R4

-15.0 TO +15.0 / -7.5 TO +7.5 /

("wc)

-3.75 TO + 3.75

0 TO 25 / -12.5 TO +12.5

R5
(pa)

0 TO 250 / 0 TO 125 / 0 TO 62.5 /

R6

-125 TO +125 / -62.5 TO +62.5 /

(pa)

-31.25 TO +31.25

0 TO 1250 / 0 TO 625 / 0 TO 312.5 /

R7

-625 TO +625 / -312.5 TO +312.5 /

(pa)

-156.25 TO +156.25

0 TO 7500 / 0 TO 3750 / 0 TO 1875 /

R8

-3750 TO +3750 / -1875 TO +1875 /

(pa)

-937.5 TO +937.5

mA

(4-20 mA
2-wire)

VDC

(0-5 VDC or
0-10 VDC field
selectable)

INSTALLATION

Inspection - Inspect the package for damage. If damaged, notify the

appropriate carrier immediately. If undamaged, open the package and
inspect the device for obvious damage. Return damaged products.

RoHS

Requirements

Mounting

Wiring

Model PR-274/275

Technical Information

TI.274/275-06

LOW PRESSURE SENSOR

Enclosure Mount

Transducer

• Tools (not provided)

- Digital Volt-ohm Meter (DVM)

- Appropriate screwdriver for mounting screws

- Appropriate drill and drill bit for mounting screws

• Appropriate accessories

• Two #8 self-tapping mounting screws (not provided)

• Training: Installer must be a qualified, experienced technician

Warning:

• Disconnect power supply before installation to prevent electrical

shock and equipment damage.

• Make all connections in accordance with the job wiring diagram

and in accordance with national and local electrical codes. Use
copper conductors only.

Caution:

• Use electrostatic discharge precautions (e.g., use of wrist straps)

during installation and wiring to prevent equipment damage.

• Avoid locations where severe shock or vibration, excessive

moisture or corrosive fumes are present. NEMA Type 4 housings
are intended for outdoor use primarily to provide a degree of
protection against wind-blown dust, rain, and hose-directed water.

• Do not exceed ratings of the device.

Caution:

• Condensate or moisture must not enter pressure sensor ports

The PR-274/275 must be mounted as indicated by the arrows on
the enclosure. Refer to Figure 7 for mounting dimensions.

1. Remove the transducer cover using a Phillips head
screwdriver.

2. Select the mounting location.

3. Mount transducer on a vertical surface with two #8
self-tapping screws (not provided).

4. Transducer must be mounted above the pressure pick-up or a
J-Loop must be incorporated in the tubing to function as a
condensate trap.

5. Pull wires through bottom of enclosure and make

necessary connections.

6. Replace cover and make pneumatic connections.

Use maximum 12 AWG wire for wiring terminals. Use flexible 1/4"
O.D. 5/32" I.D. tubing for the high and low pressure connections.
Refer to Figures 1, 2, 3, & 4 for wiring information and Figures 5 &
6 for switch designations.

(Wiring Instructions continued on pages 2 and 3.)

Panel Mount

Transducer

Page 2 of 4

Model PR-274/275

Technical Information

TI.274/275-06

RoHS

Wiring PR-274/275 Units with mA Output

PR-274/275 Low Pressure Transducer with mA Output

Zb

Zu

S

Zb

Zu

S

PR-274/275 pressure transducers with 4-20 mA output are powered with a
12-40 VDC supply.

The following describes the proper wiring of these pressure transducers with
mA output:

1. Remove the terminal block by carefully pulling it off the circuit board.

2. Locate the [+] and [-] terminal markings on the board.

3. Attach the supply voltage to the [+] lead.

4. Connect the 4-20 mA output ([-] terminal) to the controller’s input terminal.

5. Ensure that the power supply common is attached to the common bus of the
controller.

6. Re-insert the terminal block to the circuit board and apply power to the unit.

7. Check for the appropriate output signal using a DVM set on DC milliamps
connected in series with the [-] terminal.

Zb

MAMAC 9280

High

S1 S2

ON

ON

Zu

S

Zb

Low

MAMAC 9280

High

S1 S2

ON

ON

Zu

S

Low

LOW PRESSURE SENSOR

Wiring PR-274/275 Units with VDC Output

PR-274/275 Low Pressure Transducer with VDC Output

S3

Zb

Zu

S

Zb

Zu

ON

+

0

S1

ON

Zb

S2

ON

Zu

S

S3

+

0

S1

ON

S2

ON

Zu

S

High

Low

ON

Zb

S

PR-274/275 pressure transducers with VDC output are field selectable 0-5 VDC
or 0-10 VDC output and can be powered with either a 12-40 VDC or 12-35 VAC.

The following describes the proper wiring of these pressure transducers with
VDC output:

1. Remove the terminal block by carefully pulling it off the circuit board.

2. Locate the [+], [-] and [O] terminal markings on the board.

3. Attach the power wires to the [+] and [-] terminals. The [-] terminal is also the
negative terminal.

4. Connect the [O] terminal, which is the positive VDC output terminal, to the
controller’s input terminal.

5. Re-insert the terminal block to the circuit board and apply power to the unit.

6. Check the appropriate VDC output using a voltmeter set on DC volts across

the [O] and [-] terminals.

MAMAC 9280

MAMAC 9280

High

Low

TYPICAL APPLICATIONS (wiring diagrams)

Figure 1 and Figure 2 illustrate typical wiring diagrams for the mA output low

pressure transducer.

Figure 1 - Wiring for mA Low Pressure Transducers with an External DC Power
Supply

mA Output Transducer Only 12-40 VDC Power Supply

+

Figure 2 - Wiring for mA Output Transducers where the Controller or Meter has an
Internal DC Power Supply

mA Output Transducer Only

+

Caution: If you are using grounded AC, the hot wire must be on the [+] terminal. Also, if you are using a controller without built-in isolation, use an isolation transformer to supply the PR-274/275.
Caution: This product contains a half-wave rectifier power supply and must not be powered off transformers used to power other devices utilizing non-isolated full-wave rectifier power supplies.
Caution: When multiple PR-274/275 units are powered from the same transformer, damage will result unless all 24G power leads are connected to the same power lead on all devices. It is

mandatory that correct phasing be maintained when powering more than one device from a single transducer.

+

Controller / Meter / Recorder

Input Signal

+

Common

Shield/Ground

Controller / Meter / Recorder

Input Signal

+

Common

Shield/Ground

TYPICAL APPLICATIONS (wiring diagrams)

Figure 3 and Figure 4 illustrate typical wiring diagrams for the VDC output low

pressure transducer.

Figure 3 - Wiring for VDC Low Pressure Transducers When Applied with External
AC Supply

VDC Output Transducer Only 12-35 VAC Transformer

Figure 4 - Wiring for VDC Low Pressure Transducers When Applied with External
DC Power Supply

VDC Output Transducer Only 12-40 VDC Power Supply

Supply

Common

Signal

Supply

Common

Signal

Hot

+

O

+

O

+

Neutral

Controller / Meter / Recorder

Input Signal

+

Common

Shield/Ground

+

Controller / Meter / Recorder

Input Signal

+

Common

Shield/Ground

Page 3 of 4

S1

S3

+ ­0

Model PR-274/275

Technical Information

TI.274/275-06

RoHS

Figure 5 - Switch Selections for Low Pressure Transducers with mA Outputs

Zb

+ -

Range Configuration:

R1/R5 0 - 0.10 "wc / 25 pa

R2/R6 0 - 1.0 "wc / 250 pa (default)

R3/R7 0 - 5.0 "wc / 1250 pa (default)

R4/R8 0 - 30.0 "wc / 7500 pa (default)

ON

ON

1

2

1

2

S2

Zu S

S1

Uni-Directional

0 - 0.5 "wc / 125 pa

0 - 0.25 "wc / 62.5 pa

0 - 2.5 "wc / 625 pa

0 - 1.25 "wc / 312.5 pa

0 - 15.0 "wc / 3750 pa

0 - 7.5 "wc / 1875 pa

mA Output

Switch 1 (S1)

Factory

Sealed

O N

1

2

O N

1

2

O N

2

1

2

O N

1

2

O N

1

2

O N

1

2

O N

1

2

O N

1

2

O N

1

2

LOW PRESSURE SENSOR

Range Configuration:

R1/R5 +/- 0.05 "wc / 12.5 pa

R2/R6 +/- 0.5 "wc / 125 pa (default)

+/- 0.25 "wc / 62.5 pa

+/- 0.125 "wc / 31.25 pa

R3/R7 +/- 2.5 "wc / 625 pa (default)

+/- 1.25 "wc / 312.5 pa

+/- .625 "wc / 156.25 pa

R4/R8 +/- 15.0 "wc / 3750 pa (default)

+/- 7.5 "wc / 1875 pa

+/- 3.75 "wc / 937.5 pa

Output Configuration:

Uni-directional (default)

Bi-directional

Bi-Directional

Switch 1 (S1)

Factory
Sealed

O N

1

2

O N

1

2

O N

1

2

O N

1

2

O N

1

2

O N

1

2

O N

1

2

O N

1

2

O N

1

2

Switch 2 (S2)

O N

1

2

O N

1

2

Figure 6 - Switch Selections for Low Pressure Transducers with VDC Outputs

ON

1

2

S3

+ - 0

Range Configuration:

R1/R5 0 - 0.10 "wc / 25 pa

R2/R6 0 - 1.0 "wc / 250 pa (default)

0 - 0.5 "wc / 125 pa

0 - 0.25 "wc / 62.5 pa

R3/R7 0 - 5.0 "wc / 1250 pa (default)

0 - 2.5 "wc / 625 pa

0 - 1.25 "wc / 312.5 pa

R4/R8 0 - 30.0 "wc / 7500 pa (default)

0 - 15.0 "wc / 3750 pa

0 - 7.5 "wc / 1875 pa

Output Configuration:

Uni-directional (default)

Bi-directional

S1

Zb

ON

ON

1

2

1

2

Zu S

S2

Uni-Directional

VDC Output

Switch 1 (S1)

Factory
Sealed

O N

1

2

O N

1

2

O N

1

2

O N

1

2

O N

1

2

O N

1

2

O N

1

2

O N

1

2

O N

1

2

Switch 2 (S2)

O N

1

2

O N

1

2

Range Configuration:

Bi-Directional

R1/R5 +/- 0.05 "wc / 12.5 pa

R2/R6 +/- 0.5 "wc / 125 pa (default)

+/- 0.25 "wc / 62.5 pa

+/- 0.125 "wc / 31.25 pa

R3/R7 +/- 2.5 "wc / 625 pa (default)

+/- 1.25 "wc / 312.5 pa

+/- .625 "wc / 156.25 pa

R4/R8 +/- 15.0 "wc / 3750 pa (default)

+/- 7.5 "wc / 1875 pa

+/- 3.75 "wc / 937.5 pa

Output Configuration:

0 - 10 (default)

0 - 5 VDC

Switch 1 (S1)

Factory

Sealed

O N

1

2

O N

1

2

O N

1

2

O N

1

2

O N

1

2

O N

1

2

O N

1

2

O N

1

2

O N

1

2

Switch 3 (S3)

O N

1

2

O N

1

2

Page 4 of 4

Model PR-274/275

Technical Information

TI.274/275-06

RoHS

CHECKOUT

Transducer
Operation

CALIBRATION

1. Verify that the unit is mounted in the correct position.

2. Verify appropriate input signal and supply voltage.

Caution: Never connect 120 VAC to these transducers. Never
connect AC voltage to a unit intended for DC supply.

3. Verify appropriate configuration range.

This is a rough functional check only.

1. Adjust the pressure to obtain maximum output signal for
appropriate range.

2. Output should be 20 mA or 5 or 10 VDC.

3. Adjust the pressure to obtain minimum output signal.

4. Output should be 4 mA or 0 VDC.

NOTE: The PR-274/275 is a highly accurate device. For
applications requiring a high degree of accuracy, the use of
laboratory quality meters and gauges are recommended.

All units are factory calibrated to meet or exceed published
specifications. If field adjustment is necessary, follow the
instructions below.

Calibration of PR-274/275 mA Units

LOW PRESSURE SENSOR

Figure 7 - PR-274/275 Low Pressure Transducer Dimensions shown in inches

and millimeters (mm).

MAMAC

9280

2.12"

(54 mm)

2.25"

(57 mm)

Panel

Mount

Enclosure

1.56"

(40 mm)

1.12"

(28 mm)

1.12"

(28 mm)

2.20"

(56 mm)

4.50" (114 mm)

Zb

S1 S2

ONON

Z
S

5.00" (127 mm)

5.00" (127 mm)

6.00" (152 mm)

5.50" (140 mm)

MAINTENANCE

FIELD REPAIR

WARRANTY

1. Connect terminals [+] and [-] to the appropriate power
source.

2. Connect the DVM in series on the [-] terminal.

3. Apply low pressure to the unit. If configured for
uni-direction, adjust Zu trimmer to achieve desired low
output. If configured for bi-direction, adjust Zb trimmer to
achieve desired low output.

4. Apply high pressure to the unit and adjust span trimmer [S]
to obtain the desired high output pressure.

5. Repeat steps 3 and 4 until desired calibration is achieved.

Calibration of PR-274/275 VDC Units

1. Connect terminals [+] and [-] to the appropriate power
source. The [-] terminal is also the negative output terminal.

2. Connect the DVM on DC volts across [O] and [-] terminal.

3. Apply low pressure to the unit. If configured for
uni-direction, adjust Zu trimmer to achieve desired low
output. If configured for bi-direction, adjust Zb trimmer to
achieve desired low output.

4. Apply high pressure to the unit and adjust span trimmer [S]
to obtain the desired high output pressure.

5. Repeat steps 3 and 4 until desired calibration is achieved.

Regular maintenance of the total system is recommended to
assure sustained optimum performance.

None. Replace with a functional unit.

See Data Sheet for additional information.

3.25"

(83 mm)

2.50"

63.5 mm)

(

3.00" (76 mm)3.00" (76 mm)

4.00"

(102 mm)

For Technical / Application Assistance call your nearest office

8189 Century Boulevard • Minneapolis, MN 55317-8002 • USA

800-843-5116 • 952-556-4900 • Fax [phone]

[e-mail] • www.mamacsys.com

EUROPE

4200 Waterside Centre

Solihull Parkway

Birmingham • West Midlands

B37 7YN • United Kingdom

01384-271113 • Fax [phone]

ASIA

1 Fullerton Road #02-01

One Fullerton

Singapore • 049213

65-31581826 • Fax [phone]

905-474-9215 • Fax [phone]

08-8395-4333 • Fax [phone]

CANADA

675 Cochrane Drive

East Tower • 6th Floor

Toronto • Ontario

L3R 0B8 • Canada

AUSTRALIA

4 Armiger Court, Unit 2

Adelaide • S.A.
5088 • Australia

MAMAC Systems, Inc., reserves the right to change any specifications
without notice to improve performance, reliability, or function of our products.

TI.274/275-06