Dwyer 7000 User Manual

Series 7000 Spirahelic

Pressure Indicating Transmitter

Specifications - Installation and Operating Instructions

Bulletin A-33-A

(3) ø7/32 [5.56] MOUNTING

HOLES EQUALLY SPACED ON A

5-3/8 [136.53] BOLT CIRCLE

The Dwyer Series 7000 Spirahelic®Pressure Indicating Transmitter

provides local indication on a large, easy-to-read analog scale while also converting that pressure into a standard two wire 4-20 mA output signal. Positive pressure of compatible gases or liquids is measured with 1/2% of full scale accuracy. The gage employs a triple helix Bourdon tube movement with direct drive design to reduce friction and mass for exceptional responsiveness, repeatability and accuracy. Because there are no gears, springs, linkages or other complicated mechanisms, wear is practically eliminated. The electrical output signal is produced by a piezoresistive pressure sensor mounted on the pressure block. The pressure block also includes an integral filter plug to protect the gage interior from dirt and other particulates. Safety is assured with a solid front case design and a rear blowout hole.

INSTALLATION

1. Select a location free from excessive vibration where the temperature limits of 20° to 120°F (-6.7° to 49°C) will not be exceeded. The mounting surface should be vertical to match the position in which all standard gages are calibrated. Avoid locations in direct sunlight which may cause accelerated discoloration of the clear acrylic lens or where exposure to oil mist or other airborne vapors could likewise result in lens damage. Make sure that the case relief area on the rear is not obstructed. This hole is designed to direct pressure rearward in the event of failure or the Bourdon tube element. See complete safety recommendations in this bulletin.

2. Cut a 4.94˝ (125 mm) mounting hole and drill (3) 7/32˝ (5.56 mm) bolt holes on a 5.38˝ (137 mm) bolt circle as shown in drawing above. Attach gage to panel with (3) 3/16˝ bolts of appropriate length.

ø5-7/8

[149.23]

120°

23/64 [9.13]

1-9/32

[32.54]

2-5/32

[54.76]

ø4-41/64

1-13/32

2-1/32

[35.71]

[51.59]

1/4 FEMALE NPT PRESSURE CONNECTION TYP 2 PLACES

1 [25.40] SQUARE CONNECTION BLOCK

[117.87]

SPECIFICATIONS GAGE SPECIFICATIONS Service: Compatible gases & liquids Wetted Materials: Inconel®X-750 Bourdon Tube, Type 316L SS con-

nection.

Housing: Black polycarbonate case and clear acrylic cover. Accuracy: Grade 2A (0.5% F.S.). Stability: ± 1% F.S./yr. Pressure Limit: 150% of full scale. Gage will maintain its specifica-

tions for overpressures up to 150% maximum range. Normal operation should be between 25% and 75% of full scale.

Temperature Limits: 20 to 120°F (-6.67 to 48.9°C). Size: 4 -1/2˝ dial face (114.3 mm), Design conforms to ASME B40.1. Process Connections: Two 1/4˝ female NPT field selectable back or

bottom connection.

Weight: 17.1 oz (581 g).

TRANSMITTER SPECIFICATIONS Accuracy: 0.5% F.S. Temperature Limits: 20 to 120°F (-6.67 to 48.9°C). Thermal Effect: ±0.025% F.S. /°F (0.045% F.S./C°). Power Requirements: 10-35 VDC (2 wire). Output Signal: 4-20 mA DC. Zero & Span Adjustments: Externally accessible potentiometers. Loop Resistance: DC, 0-1250 ohms. Current Consumption: DC, 38 mA max. Electrical Connections: Screw Terminals. Mounting Orientation: Vertical. Agency Approvals: CE.

3. Two 1/4˝ female NPT pressure connections are furnished to allow a choice of vertical or horizontal piping. The unused port should be plugged. Use a minimal amount of thread sealant. Too much could block the internal pressure passage.

DWYER INSTRUMENTS, INC.

Phone: 219/879-8000 www.dwyer-inst.com

P.O. Box 373 • Michigan City, IN 46361-0373, U.S.A. Fax: 219/872-9057 e-mail: info@dwyer-inst.com

CAUTION: When installing fittings or pipe always us a second wrench on

MAXIMUM VALUE (1300 OHMS)

1400

1300

1200

1100

1000

900

800

700

600

500

400

300

200

100

15 20 25

30 35

OPERATING

REGION

RECEIVER RESISTANCE (OHMS)

R L MAX =

Vps-10.0

20mA DC

7000 SERIES

INDICATING PRESSURE

TRANSMITTER

POWER SUPPLY

10-35 VDC

RECEIVER

SPAN ADJUST

ZERO ADJUST

TERMINAL BLOCK

SPIRAHELIC INDICATING TRANSMITTER

RANGE:

SPAN

ZERO

7000

the 1˝ pressure block DO NOT allow torque to be transmitted from block to the gage case.

PNEUMATIC CALIBRATION TESTER

Use a dead weight tester or certified test gage with .125% or better accuracy. The test gage range should be comparable to the range of the Spirahelic®Pressure Indicating Transmitter being checked. Connect the lines from the two instruments to a tee and the third line from the tee to a controllable source of pressure. Apply pressure slowly so pressure equalizes throughout the system. Compare readings, if gage being tested is found to need calibration, return it, freight prepaid to the factory.

ELECTRICAL CONNECTIONS CAUTION: Do not exceed specified supply voltage ratings. Permanent

damage not covered by warranty will result. This unit is not designed for 120 or 240 volt AC line operation.

Electrical connections to the Series 7000 Spirahelic®Pressure Indicating Transmitter are made at the rear of the pressure gage. Feed stripped and tinned leads to the terminal block screws shown below, refer to Figure A for locations of the terminal block, span and zero adjustments.

Fig. B

Fig. C

Fig. A

2-Wire Operation - A 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 (R

) for the DC power supply voltage available is expressed by the formula and graph in Figure C. 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.

PRESSURE RANGING

Each standard Series 7000 Spirahelic

Pressure Indicating Transmitter is factory calibrated to produce a 4 mA output signal at zero pressure and a 20 mA signal at full scale. Use the following procedure to check or adjust the output signal calibration.

1. With the unit connected to its companion receiver and power supply, an accurate milliammeter should be inserted in series with the current loop. A controllable pressure source capable of achieving the necessary full scale pressure should be connected to the pressure port of the transmitter and teed to an accurate pressure gage or manometer. The instrument should be calibrated in the same position in which it will be used. Vertical mounting is recommended.

2. Apply electrical power to the system and allow it to stabilize for 10 minutes.

3. With no pressure applied to the transmitter, adjust “Zero” control so that loop current is 4 mA.

4. Apply full scale pressure and adjust “Span” control so that loop current is 20 mA.

5. Relieve pressure and allow transmitter to stabilize to 2 minutes.

6. Zero and Span controls are slightly interactive so repeat steps 3 through 5 until zero and full scale pressures consistently produce loop currents of 4 and 20 mA respectively.

7. Remove milliammeter from the current loop and proceed with final installation of the transmitter and receiver.

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