Dwyer Instruments 631 Series User manual

Series 631 Differential Pressure Transmitter
Specications - Installation and Operating Instructions
Bulletin E-114
The Series 631 Differential Pressure Transmitter monitors differential pressure
of air and compatible gases and liquids. The design employs converting pressure
changes into a standard 4-20 mA output signal for two wire circuits. Digital push-button,
zero and span adjustments are easily accessed on the front cover. The Series 631
Differential Pressure Transmitter is designed to meet NEMA-4X (IP66) construction.
INSTALLATION
1. Location: Select a location where the temperature of the unit will be between 20 and
120°F. Distance from the receiver is limited only by total loop resistance (see
electrical connections). The tubing feeding pressure to the instrument can be
practically any length required, but long lengths will increase the response time
slightly. Mount the instrument in a location that will not be subject to excessive
temperature, shock or vibration.
2. Position: A vertical position is recommended (pressure connections pointing
vertically) since that is how all standard models were originally spanned and
zeroed at the factory.
3. Pressure Connection: Dual 1/4˝ female NPT pressure connections are provided.
Use pipe thread sealant tape or other suitable pipe joint compound when making
connection to the pressure source. Avoid excess sealant which could block the
pressure passage. When monitoring liquid pressures, air trapped in the lines can
cause incorrect readings. Bleed ttings or similar mechanisms should be used to
bleed off any trapped air.
SPECIFICATIONS
Service: Compatible gases & liquids.
Wetted Materials: Brass, silicone, 300 SS.
Accuracy: Transmitter Output: ±2% F.S. (includes linearity, hysteresis and
repeatability); Gage: ±3% of full scale at 70°F (21.1°C).
Stability: ±1% F.S./yr.
Temperature Limits: 20 to 120°F (-6.67 to 48.9°C).
Pressure Limits: -20˝ Hg to 500 psig. (-0.677 bar to 34.4 bar).
Thermal Effect: Greater than 1˝ ranges: ±0.025%/°F (±0.045%/°C); 1˝ range:
±0.045%/°F (±0.081%/°C); 0.5˝ range: ±0.09%/°F (±0.162%/°C).
Power Requirements: 10-35 VDC.
Output Signal: 4 to 20 mA.
Response Time: 50 msec.
Loop Resistance: 0-1250 ohms maximum.
Electrical Connections: M-12 circular 4 pin connector.
Process Connections: 1/4˝ female NPT high and low pressure taps, duplicated -
one pair top for air and gas, and one pair bottom for liquids.
Enclosure Rating: Designed to meet NEMA 4X (IP66).
Mounting Orientation: Diaphragm in vertical position. Consult factory for other
position orientations.
Weight: 8 lb, 4 oz (3.74 kg).
Agency Approvals: CE.
5
[127.00]
4-45/64
[119.46]
3-13/32
[86.52]
13/32
[10.32] TYP 3/16
[4.76]
1/4 FEMALE NPT LOW
PRESSURE CONNECTION (LIQUID)
(4) #6-32 X 3/8 [9.53] DP
HOLE ON A 4-11/32 [110.33]
BOLT CIRCLE
1/4 FEMALE NPT HIGH
PRESSURE CONNECTION (LIQUID)
1/4 FEMALE NPT LOW
PRESSURE CONNECTION
(AIR OR GAS)
1/4 FEMALE NPT HIGH
PRESSURE CONNECTION
(AIR OR GAS)
3/4 [19.05] TYP
35° TYP
®
DWYER INSTRUMENTS, INC.
P.O. BOX 373 • MICHIGAN CITY, INDIANA 46360, U.S.A.
Phone: [phone]
Fax: [phone]
www.dwyer-inst.com
e-mail: [email protected]

Printed in U.S.A. 1/19 FR# 443311-00 Rev. 5©Copyright 2019 Dwyer Instruments, Inc.
DWYER INSTRUMENTS, INC.
P.O. BOX 373 • MICHIGAN CITY, INDIANA 46360, U.S.A.
Phone: [phone]
Fax: [phone]
www.dwyer-inst.com
e-mail: [email protected]
ELECTRICAL CONNECTIONS
CAUTION: Do not exceed specied supply voltage ratings. Permanent damage not
covered by warranty will result. This unit is not designed for 120 or 240 volt AC line
operation.
Wire Length - The Maximum length of wire connecting transmitter and receiver is a
function of wire size and receiver resistance. Wiring should not contribute to more than
10% of receiver resistance to total loop resistance. For extremely long runs (over 1000
ft.), choose receivers with higher resistance to minimize size and cost of connecting
leads. When the wiring length is under 100 feet, lead wire as small as 22 AWG can
be used.
Current (4 to 20 mA) Output Operation - An external power supply delivering 10-35
VDC with minimum current capability of 40 mA DC (per transmitter) must be used to
power the control loop. See Figure B for connection of the power supply, transmitter,
and receiver. The range of the appropriate receiver load resistance (RL) for the DC
power supply voltage available is expressed by the formula:
RL Max =
Shielded two wire cable is recommended for control loop wiring. If grounding is
required use negative side of control loop after receiver, see Figure B.
MULTIPLE RECEIVER INSTALLATION
An advantage of the standard 4 to 20 mA DC output signal provided by the Series 631
Differential Transmitter is that any number or receivers can be connected in series
in the current loop. Thus, an A-701 digital readout, an analog panel meter, a chart
recorder, process controlling equipment, or any combination of these devices can be
operated simultaneously. It is necessary only that each be equipped with a standard 4
to 20 mA input and proper polarity of the input connections be observed when inserting
the device into the current loop. If any of the receiving devices displays a negative or
downscale reading this indicates that the signal input leads are reversed.
MOUNTING OPTIONS
MAINTENANCE
Upon nal installation of the Series 631 Differential Pressure Transmitter and the
companion receiver, no routine maintenance is required. A periodic check of the
system calibration is recommended. The Series 631 Differential Pressure Transmitter
is not eld serviceable and should be returned if repair is needed (eld repair should
not be attempted and may void warranty). Be sure to include a brief description of the
problem plus any relevant application notes. Contact customer service to receive a
return goods authorization number before shipping.
SERIES 631
PRESSURE
TRANSMITTER
POWER
SUPPLY
10-35 VDC
RECEIVER
1
2
Figure A
Figure B
Vps – 10
20 mA DC
1/4 (6.35) HOLES IN PANEL
FOR BLOWOUT PASSAGE
3/4 (19.05) HOLE IN PANEL
FOR ELECTRICAL
CONNECTION
42 - TYP 2 PLACES
35
(4) 3/16 (4.76) HOLES IN PANE
L
EQUALLY SPACED ON A
4-11/32 (110.33) B.C.
SURFACE MOUNT HOLE PATTERN
This symbol indicates waste electrical products should not be disposed
of with household waste. Please recycle where facilities exist. Check with
your Local Authority or retailer for recycling advice.