Dwyer 634ES User Manual

Bulletin E-69ES

2-1/2 [63.50]

TYP

1-11/16

[42.86]

5-5/16

[134.94]

1/4NPT

1/2NPT

2-7/8 [73.03]

1/16 [1.59]
25/32 [19.84]

03-3/8 [85.73]

3/4 NPT

1-9/16

[39.69]

(3) #10-32 x 1/4 [6.35] DP HOLES

EQUALLY SPACED ON A 2-1/2 [63.50] B.C.

Series 634ES Pressure Transmitter

Specifications - Installation and Operating Instructions

The Series 634ES Pressure Transmitter senses a single air, compati-
ble gas or liquid pressure and converts it into a standard 4-20 mA output
signal. Ranges are available from 0-10 through 0-6000 psi. All models
are field adjustable so any range within these limits can be achieved by
recalibration using the easily accessible span and zero potentiometers.

Positive pressure can be measured within an accuracy of ±0.5% of span.
The Series 634ES uses an isolated piezoresistive pressure sensor to
produce a resistance change across a wheatstone bridge. The signal is
conditioned and converted into a 4-20 mA output signal.

For applications requiring direct pressure or percent of full span read­ings, the optional A-701 digital readout makes an ideal companion
device, providing a bright .6” high, 3-1/2˝ digit LED and supplying power
to the Series 634ES Transmitter.

Series 634ES Models and Ranges in PSI (bar)
Model
634ES-0
634ES-1
634ES-2
634ES-3
634ES-4
634ES-5
634ES-6
634ES-7
634ES-8
634ES-9

As Stocked

10 (.69)

30 (2.07)

50 (3.45)

100 (6.9)

200 (13.8)

300 (20.7)

500 (34.5)

1000 (69)

2000 (138)

4000 (276)

Min. Range

10 (.69)
20 (1.38)
40 (2.76)
60 (4.14)
100 (6.9)
250 (17.2)
350 (24.1)
600 (41.4)
1250 (86)
2500 (172)

Max. Range

20 (1.38)
40 (2.76)
60 (4.14)
120 (8.3)
250 (17.2)
350 (24.1)
600 (41.4)
1250 (86)
2500 (172)
6000 (414)

Max. Pressure

30 (2.07)
60 (4.14)
100 (6.9)
200 (13.8)
400 (27.6)
500 (34.5)
1000 (69)
2000 (138)
4000 (276)
7500 (517)

PHYSICAL DATA
GENERAL
Maximum Pressure: See chart on this page.
Wetted Parts: 316, 316L SS.
Housing: Designed to meet NEMA-4X.

ELECTRICAL
Power Supply: 12.3-35 VDC-2 wire.
Output Signal: 4-20 mA DC (limited at 38 mA DC).
Loop Resistance: 0 - 1100 ohms from 12.3 to 35 VDC.

Vps - 12.3V

=

R

L max

20 mA

Current Consumption: DC: 38 mA max.

MATERIALS
Housing: Cast aluminum; textured gray polyurethane finish.
Pressure Connection: Stainless Steel.

MECHANICAL
Weight: 1 lb, 12 oz (.8 kg).
Span and Zero Adjustments: Protected potentiometers, located in

auxiliary housing.

Pressure Connection: 1/4˝ female NPT x 1/2˝ male NPT.

PERFORMANCE AT 70°F (21.1°C)
Zero Output: 4 mA DC.
Full Span: 16 mA DC.
Accuracy: ±0.5% of span.
Warm-up Time: 10 minutes.

STABILITY/ENVIRONMENTAL
Operating Temperature: 20 to 120˚F (- 6.7 to 48.9˚C).
Thermal Errors: ± 0.02%/˚F typical.
Stability: 1% F.S./yr.

STANDARD ACCESSORIES

(3) “Z” mounting brackets.
(3) 10-32 x 4˝ RH machine screws.

DWYER INSTRUMENTS, INC.

P.O. Box 373 • Michigan City, IN 46361 U.S.A. Fax: [phone] e-mail: [e-mail]

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

INSTALLATION

LOCATION: Select a location where temperature of the unit will be

between 20°F and 120°F. Distance from the receiver is limited only by
total loop resistance. See “Electrical Connections.” The tube feeding the
pressure to the instrument can be run practically any length required, but
long lengths will slightly increase response time. Avoid surfaces with
excessive vibration.

POSITION: A vertical position is recommended, as all stocked models
are spanned and zeroed at the factory in this position. They can be used
at other angles, but final spanning and zeroing must be done while trans­mitter is in the alternative position.

PRESSURE CONNECTIONS: A single pressure connection is provided
at the bottom of the transmitter housing. It has1/4” female NPT and 1/2”
male NPT threads. Attach positive pressure to this port.

MOUNTING: The Series 634ES Transmitter can be mounted three ways:

(A) Supported directly by pipe providing pressure.

(B) Attached to a mounting surface with 10-32 x 1/4” machine screws
(included). The machine screws are installed through the mounting sur­face into tapped holes on back of unit.

(C) Mounted with “Z” brackets (included). Attach “Z” brackets to tapped
holes on back of unit and fasten to front of mounting surface.

ELECTRICAL CONNECTIONS

CAUTION: DO NOT EXCEED SPECIFIED SUPPLY VOLTAGE RAT-

INGS. PERMANENT DAMAGE NOT COVERED BY WARRANTY WILL
RESULT. THIS UNIT IS NOT DESIGNED FOR AC VOLTAGE OPERA­TION.

Electrical connections to the Series 634ES Transmitter are made inside
the enclosure. Remove the cover, feed stripped and tinned leads through
the conduit opening and connect to terminal block screws marked + and

-. See Figure A for locations of terminal block, span and zero adjust
potentiometers. See Figure B (Pg. 3) for schematic diagram.

FIG. A

An external power supply delivering 12.3 to 35 VDC with minimum cur­rent capability of 40 mA must be used to power the control loop in which
the Series 634ES Transmitter is connected. See Figure B for connection
of the power supply, transmitter and receiver.

The range of appropriate receiver load resistance (RL) for the power sup­ply voltage available is given by the formula and graph in Figure C on Pg.

3.

Shielded 2-wire cable is recommended for control loop wiring, and the
cable shielding may be grounded if desired. Note also that the receiver
may be connected in either the negative or positive side of the loop,
whichever is most convenient.

Should polarity of the transmitter or receiver inadvertently become
reversed, the loop will not function properly, but no damage will be done
to the transmitter.