Dwyer Instruments ISDP Operating Manual

Bulletin A-25

Series ISDP Intrinsically Safe Differential Pressure Transmitter

Specifications - Installation and Operating Instructions

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

25/32

[21.18]

1-15/16

[48.97]

1-5/16

[33]

1-17/32

[38.61]

45/64

[17.78]

5-7/32

[132.54]

4-23/32

[120]

3-7/16

[87.12]

BRACKETS

ARE OPTIONAL

4X ø3/16 [4.76] CLEARANCE

HOLES FOR MOUNTING

3-17/64

[83]

MOUNTING HOLE

PATTERN

4-1/8
[105]

1-5/32

[29.59]

#8-36 SLOTTED MACHINE SCREW

#8 LOCK

WASHER

BRACKET ASSEMBLY

1-45/64

[43.18]

2-31/32

[75.39]

4-23/32

[120]

4-9/64

[105.17]

DIMENSIONS

Shown with Optional A-438 Mounting Bracket

OPTIONAL A-438 BRACKET

MOUNTING DIAGRAM

1

SPECIFICATIONS
Service: Air and non-corrosive gases.
Wetted Materials: Ranges 5˝ and greater: glass, PVC, silicon, alumina ceramic, epoxy,

RTV, gold, aluminum, stainless steel and nickel; Ranges 1˝ and lower: stainless steel, sil­icone, gold and ceramic.

Housing Materials: Aluminum, glass.
Accuracy: ±0.5% at 77°F (25°C) including hysteresis and repeatability (after 1 hour

warm-up).

Stability: < ±1% per year.
Pressure Limits: Ranges ≤ 2.5 in. w.c. = 2 psi;

5˝: 5 psi; 10˝: 5 psi; 25˝: 5 psi; 50˝: 5 psi; 100˝: 9 psi.

Temperature Limits: 32 to 140°F (0 to 60°C).
Compensated Temperature Limits: 32 to 140°F (0 to 60°C).
Thermal Effects: 0.020%/°F (0.036/°C) from 77°F (25°C).
Power Requirements: 10-35 VDC.
Output Signal: 4-20 mA DC.
Zero & Span Adjustments: Accessible via menus.
Response Time: 250 ms (dampening set to 1).
Display: 4 digit LCD 0.6˝ height.
Electrical Connections: M12 4 PIN Connector.
Process Connections: 1/8 female NPT.
Enclosure Rating: Designed to meet NEMA 4x (IP66).
Mounting Orientation: Mount unit in horizontal plane.
Size: 4.73˝ x 4.73˝ x 3.43˝ (120 mm x 120 mm x 87.1 mm).
Weight: 2 lb 10 oz (1.19 kg).
Agency Approvals: FM, C-FM Intrinsically Safe CL1 Div 1 GR: A, B, C, D; CL2 Div 1

GR: E, F, G; CL3 Div 1 CE. CENELEC EN 61326/55024: 2003; IEC 61000-4-2/3/4/6:
2001/2006/2004/2005; CENELEC EN 55011: 2006; 2004/108/EC EMC Directive.

Intrinsic Safety Information

Entity Parameters

Ui = 28VDC
Ii = 93mA
Ci = 22 nF
Li = 400 uH
Pi = 651mW

Intrinsically Safe for the following hazardous areas:

CLASS I DIV. 1 GROUPS A, B, C, D
CLASS II DIV. 1 GROUPS E, F, G
CLASS III DIV. 1 T4

Notes:

1. Remove power from the instrument before carrying out any servicing.

2. Return the instrument to the manufacturer for any repair. Any unauthorized repairs
may impair the intrinsic safety of the instrument.

3. Use only FM approved Associated Apparatus.

4. Install in accordance with ANSI/ISA RP12.06.01, the National Electric Code
ANSI/NFPA 70, in the US, and the Canadian electrical code in Canada.

5. The earth terminal on the housing must be wired to a local earth ground in the
hazardous area.

2

MAXIMUM VALUE (1250Ω)

OPERATING 

REGION

R L MAX=

Vps-10.0

20mA DC

VDC

0

5101315

20

25

30

35

TO

TAL R

E

C

EIVE

R

R

E

SISTAN

C

E (

Ω)

1500
1400
1300
1200
1100
1000

900
800
700
600
500
400
300
200
100

50

40

ISDP

TRANSMITTER

RECEIVER

POWER
SUPPLY

10-35 VDC

mA

SP/AL

MEMENU

SP/AL

MENU

SP/AL

MENU

SP/AL

MENU

E

M-12 Connector

3

2

1

4

+

A-231 M-12 Cable Colors

PIN 1 is Brown (positive)

PIN 3 is Blue (negative)

Use Model A-231 shielded cable with 4 pin Female M-12 connection.

2-WIRE CONNECTION

Fig. C

2-Wire 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 Fig.
C 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 and graph in Fig. D.

POWER SUPPLY VOLTAGE - VDC (2-WIRE CONNECTION)

Fig. D

3

SP/AL

MENUMENU

SP/AL

MENU

SP/AL

MENU

SP/AL

MENU

E

INSTALLATION

Mount the instrument in a location that will not be subject to excessive temperature, shock
or vibration.

Pressure Connections

Use 1/8˝ male NPT fittings. When tightening fittings, grasp the brass fitting on the ISDP
with a 1/2˝ wrench to prevent the fitting on the ISDP from turning.

KEY FUNCTIONS

MENU

HOME POSITION
FUNCTION

Allows access to
the menus

MAIN MENU
FUNCTION

Return to home
position

SUB MENU
FUNCTION

Return to previous menu

UP

ARROW

DOWN

ARROW

ENTER

Displays full scale
range of unit

Sequences through menus

Sequences through menus

Enter into SUB MENU

4

Increments a value

Decrements a value

Changes a value or
setting. Press ENTER and
display will blink. Adjust
with UP or DOWN arrows.
Press ENTER to store.
Display will stop blinking.

Peak/Valley SUB MENU
resets display to present
value.

SP/AL

MENU

SP/AL

MENU

MENU MAP

CONTINUED

SETTINGS

MAIN MENUS SUB MENUS

SP/AL

MENU

SP/AL

MENU

SP/AL

MENU

E

SP/AL

MENUMENU

MAIN MENUS

SUB MENUS

MENU MAP

MENU MAP

SETTINGS

SETTINGS

CONTINUED

CONTINUED

MENUS

MENUS

UNAVAILABLE

UNAVAILABLE

FOR

FOR

BI-DIRECTIONAL

BI-DIRECTIONAL

RANGES AND

RANGES AND

RANGES ABOVE

RANGES ABOVE

25 IN. W.C.

25 IN. W.C.

5

CONTINUEDCONTINUED

SETTINGS

SP/AL

MENU

SP/AL

MENU

SP/AL

MENU

E

SP/AL

MENUMENU

CONTINUED

6

MAIN MENUS SUB MENUS

SETTINGS

SP/AL

MENU

SP/AL

MENU

SP/AL

MENU

E

SP/AL

MENUMENU

MAIN MENUS

SUB MENUS

SETTINGS

Menus present only

in pressure operation

7

Model Chart
Model

ISDP-002
ISDP-004
ISDP-005
ISDP-006
ISDP-007
IDSP-008
ISDP-009
ISDP-010
ISDP-011
ISDP-012
ISDP-013
ISDP-014
ISDP-015
ISDP-016
ISDP-017

Range

0-0.25˝
0-1˝ WC
0-2.5˝ WC
0-5˝ WC
0-10˝ WC
0-25˝ WC
0-50˝ WC
0-100˝ WC

-0.1/+0.1˝ WC

-0.25/+0.25˝ WC

-0.5/+0.5˝ WC

-1.0/+1.0˝ WC

-2.5/+2.5˝ WC

-5.0/+5.0˝ WC

-10/+10˝ WC

Main Menu Selections (Upper Right Display Reads

SECr

OPEr

diS

AdU

Security - Lock out access to menus and settings.

Operation - Selection of Pressure, Velocity or Flow and corresponding
engineering units.

Display - Monitor and adjust display related settings: Peak, Valley, display

resolution, % output and dampening.

Advanced functions - Modify advanced function parameters, transmitter

output scaling, and calibration.

MENU

)

8

MAIN MENUS and SUB MENUS

Units visible, so unit
is presently set to
measure pressure

is presently set to
measure pressure

Units not visibleUnits not visible Units not visibleUnits not visible

SECr

(Security) MAIN MENU

SECr

is the only SUB MENU in the security MENU. When the security SUB MENU
is selected, the present security level is displayed in the upper right hand display. To
change the security level, adjust the number displayed to the number shown in the
following table for the desired security level.

Security Level
Displayed

1

2

Access

All menus access

All settings locked

Password Value
to Enter

10

70

The password values shown in the table cannot be altered, so retain a copy
of these pages for future reference.

OPEr

(Operation) MAIN MENU

The

OPEr

MENU selects the measurement type of the instrument.

The SUB MENUS are:

PrES

- Pressure

UEL

- Velocity

FLO

- Flow

If the instrument is set for Velocity, the
MENU. If the instrument is set for Flow, the

ArEA

SUB MENUS. These will be discussed under Velocity and Flow. When scrolling

through the

OPEr

SUB MENUS, the measurement type the unit is currently set for will

KFAC

ArEA

DIA

- Diameter

OPEr

- K Factor

- Area

XDIM

YDIM

MENU will have an additional

OPEr

MENU will have additional

- X Dimension

- Y Dimension

KFAC

KFAC

SUB

and

show the units in the upper right display. The other measurement types will have a blank
upper right display.

9

PrES

(Pressure) SUB MENU

For pressure measurement, the following units are available:

INWC

- Inches of water column

FTWC

- Feet of water column

MMWC

- Millimeters of water column

CMWC

- Centimeters of water column

PSI

- Pounds per square inch

INHG

- Inches of mercury

Table 1 Pressure Range vs. Available Units

INWC

FTWC

.1000
.2500
.5000

1.000

2.500

5.000

10.00

25.00

50.00

100.0

NOTE:

exceeded above or below full scale by 2%.

.2083
.4167
.8333

2.083

4.167

8.333

OVFL

(over flow) or

MMWC

2.540

6.350

12.70

25.40

63.50

127.0

254.0

635.0
1270
2540

CMWC

.2540
.6350

1.270

2.540

6.350

12.70

25.40

63.50

127.0

254.0

UnFL

PSI

.1806
.3613
.9032

1.806

3.613

(under flow) will appear when the ranges have been

INHG

.1839
.3678
.7356

1.839

3.678

7.356

MMHG

- Millimeters of mercury

MBAR

- Millibar

PA

- Pascal

KPA

- Kilopascals

HPA

- Hectopascals

OZIN

- Ounce inches

MMHG

.1868
.4671
.9342

1.868

4.671

9.342

18.68

46.71

93.42

186.8

MBAR

.2491
.6227

1.245

2.491

6.227

12.45

24.91

62.27

124.5

249.1

PA

24.91

62.27

124.5

249.1

622.7
1245
2491
6227

KPA

.1245
.2491
.6227

1.245

2.491

6.227

12.45

24.91

HPA

.2491
.6227

1.245

2.491

6.227

12.45

24.91

62.27

124.5

249.1

OZIN

.1445
.2890
.5780

1.445

2.890

5.780

14.45

28.90

57.80

UEL

(Velocity) SUB MENU

For velocity measurement, the following units are available:

SFPM

- Standard feet per minute

M/S

- Meters per second

Table 2 Available Velocity Ranges

INPUT RANGE INWC

0 - 0.1
0 - 0.25
0 - 0.5
0 - 1
0 - 2.5
0 - 5
0 - 10
0 - 25

NOTE: Air velocity and flow readings are based upon standard dry air conditions with an
ambient temperature of 70°F and a barometric pressure of 29.92 INHG.

SFPM RANGE

0 - 1266
0 - 2002
0 - 2832
0 - 4004
0 - 6332
0 - 8954
0 - 12.66 x IK
0 - 20.02 x IK

M/S RANGE

0 - 6.431
0 - 10.17
0 - 14.39
0 - 20.35
0 - 32.17
0 - 45.48
0 - 64.33
0 - 101.7

10

FLO

(Flow) SUB MENU

For flow measurements the following units are available:

SCFM

- Standard cubic feet per minute

M^3H

- Cubic meters per hour

FLO r

(Flow Range) SUB MENU

LO

- 99.99 x 1K flow range

HI

- 999.9 x 1K flow range

Tables 3 -6 show the flow ranges available, and the maximum duct size that can be set for
each input range.

Table 3

FLOr = LO

RANGE
IN WC

0.1

0.25

0.5

1

2.5

5

10

25

Table 5

FLOr = LO

RANGE
IN WC

0.1

0.25

0.5

1

2.5

5

10

25

KFAC

SUB MENU

Maximum Duct Size (English)

SCFM
RANGE

99.99 x 1K

99.99 x 1K

99.99 x 1K

99.99 x 1K

99.99 x 1K

99.99 x 1K

99.99 x 1K

99.99 x 1K

MAX. DUCT
SIZE, SQ. FT.

78.9

49.9

35.3

24.9

15.7

11.1

7.8

4.9

Maximum Duct Size (Metric)

Mˆ3/Hr
RANGE

99.99 x 1K

99.99 x 1K

99.99 x 1K

99.99 x 1K

99.99 x 1K

99.99 x 1K

99.99 x 1K

99.99 x 1K

MAX. DUCT
SIZE Mˆ2

4.32

2.73

1.93

1.37

0.86

0.61

0.43

0.27

Table 4

FLOr = HI

RANGE
IN WC

0.1

0.25

0.5

1

2.5

5

10

25

Table 6

FLOr = HI

RANGE
IN WC

0.1

0.25

0.5

1

2.5

5

10

25

Maximum Duct Size (English)

SCFM
RANGE

999.9 x 1K

999.9 x 1K

999.9 x 1K

999.9 x 1K

999.9 x 1K

999.9 x 1K

999.9 x 1K

999.9 x 1K

MAX. DUCT
SIZE, SQ. FT.

789.8

499.5

353.1

249.7

157.9

111.7

78.9

49.9

Maximum Duct Size (Metric)

Mˆ3/Hr
Range

999.9 x 1K

999.9 x 1K

999.9 x 1K

999.9 x 1K

999.9 x 1K

999.9 x 1K

999.9 x 1K

999.9 x 1K

MAX. DUCT
SIZE, Mˆ2

43.19

27.31

19.3

13.64

8.63

6.10

4.31

2.73

KFAC

K Factor - becomes accessible if the instrument is set for Velocity or Flow. When

the Digihelic

®

II Controller is used with a Pitot tube, the manufacturer may specify a K

Factor. The adjustment range is 0.01 to 2.00. The factory setting is 1.

11

ArEA, DIA, XDIM

These SUB MENUS become accessible if the instrument is set for flow. When measuring
flow, the area of the duct must be specified. Tables 3 and 4 show the input range vs max­imum flow and duct size. For a rectangular duct the maximum size is specified in square
feet or meters. For a circular duct the maximum size is specified as the diameter. X, Y and
circular dimensions are entered in feet with 0.01 foot resolution for
resolution for

ArEA

circular duct is selected, the

DIA
XDIM
YDIM

and

YDIM

SUB MENUS

FLOr = HI

- Area, select

selected, the

- Diameter, enter the diameter of a duct

- Enter the “X” dimension of a duct

- Enter the “Y” dimension of a duct

, or entered in millimeters with 1 millimeter resolution.

CIR

for a circular duct or

DIA

SUB MENU will be activated. If a rectangular duct is

XDIM

and

YDIM

SUB MENUS will be activated.

FLOr = LO

RECT

for a rectangular duct. If a

and 0.1 foot

Y

X

d.S

(Display) MAIN MENU

PEAK
VALy
ZERO

- Peak value

- Valley value

- Zero

rESO

- Resolution

Pd.S

- Process display

DAMP

- Dampening level

PEAK

(Peak) SUB MENU

The Peak feature stores the highest pressure reading the instrument has measured

since the last reset or power up. At power up

pressure reading. To manually reset the

the

PEAK

SUB MENU.

VALy

(Valley) SUB MENU

The valley feature stores the lowest pressure reading the instrument has measured

since the last reset or power up. At power up

pressure reading. To manually reset the

the

VALy

SUB MENU.

PEAK

VALy

12

PEAK

is reset to the present

value, press the ENTER key while in

VALy

is reset to the present

value, press the ENTER key while in

rESO

(Resolution) SUB MENU

The Series ISDP Controller is capable of displaying four digits of resolution.

However, at very low pressures the instability of the pressure may cause
fluctuations in the least significant digit causing the least significant digit to be of
little value.
Three digit resolution (
the right of a decimal.

3DIG

- Set display for 3 digit resolution

4DIG

- Set display for 4 digit resolution

Pd.S

(Process Display) SUB MENU

STD

- Display reads pressure, velocity, or flow values

PCT

- Display reads % of full scale value

3DIG

) can only be active when there is at least one digit to

When the display is reading percent,
display. The percent display is only available in pressure operation.

DAMP

(Dampening) SUB MENU

Adjust from 1-16

Dampening stabilizes the display from instabilities due to things such as vibration
and excessive pressure fluctuations. The dampening setting adjusts the amount of
readings that are averaged for each display update. Adjust the dampening value
until the display reads a stable value for the application.

AdU

(Advanced) MAIN MENU

POL

- Process output low

POH

- Process output high

ZERO

- Zero calibration

SPAN

- Span calibration

POL

and

POH

(Process Output Low and High) SUB MENUS

This feature is used in pressure operation only.

Process output low and high are used to scale the 4-20 mA output. Set
desired display reading for 4mA output, and set
reading for 20 mA output.
BELOW minimum scale up to
maximum scale.

POH

must be higher than

POH. POH

PCT

is displayed in the upper right of the

POH

to the desired display

POL. POL

may be adjusted from

may be adjusted 2%

POL

to 2% ABOVE

POL

to the

13

ZERO

and

SPAN

(Calibration of Zero and Span) SUB MENUS

The lower display reads

ZERO

Calibration

NOTE: For accurate calibration, DO NOT apply any pressure when performing

this function.

With the display reading
Press ENTER again to complete the zeroing of the instrument or press the
key to cancel.

SPAN

Calibration

With the display set to
key. The upper display will blink. Press ENTER again to complete the calibration or
press the

Maintenance

Upon final installation of the Series ISDP intrinsically Safe Differential Pressure
Transmitter, no routine maintenance is required. The Series ISDP is not field serviceable
and should not be returned if repair is needed (field 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.

MENU

key to cancel.

CAL

in this mode.

ZERO

, press the ENTER key. The upper display will blink.

SPAN

, apply full scale pressure to the unit. Press the ENTER

MENU

14

FM APPROVED

ASSOCIATED APPARATUS

ISDP SERIES TRANSMITTER

Vmax = 28VDC

Imax = 93mA

Ci = 22nF

Li = 400uH

CATALOG NUMBERS

ISDP-001 THROUGH ISDP-017

Pi = 651mW

HAZARDOUS (CLASSIFIED) LOCATION

GROUND

I.S. SAFETY

NON-HAZARDOUS LOCATION

OPTIONAL SHIELD

INTRINSICALLY SAFE FOR:

CLASS I DIV. 1 GROUPS A, B, C, D

CLASS II DIV. 1 GROUPS E, F, G

CLASS III DIV. 1

T4 TEMPERATURE CODE BASED ON

71° AMBIENT

1. THE INTRINSIC SAFE ENTITY CONCEPT ALLOWS THE INTERCONNECTION OF TWO FM APPROVED INTRINSICALLY

SAFE DEVICES WITH ENTRY PARAMETERS NOT SPECIFICALLY EXAMINED IN COMBINATION AS A SYSTEM WHEN:

Voc OR Uo OR Vt ≤ Vmax, Isc OR It ≤ Imax ≤ Ca or Co ≥ Ci + Ccable, La OR Lo ≥ Li + Lcable, Po ≤ Pi

2. EQUIPMENT CONNECTED TO THE ASSOCIATED APPARATUS MUST NOT USE OR GENERATE MORE THAN 250 Vrms OR VDC.

3. INSTALLATION MUST BE IN ACCORDANCE WITH THE NATIONAL ELECTRICAL CODE (NFPA 70, ARTICLE 504) IN US,

CANADIAN ELECTRICAL CODE IN CANADA AND ANSI/ISA-RP12.6.

4. NO REVISIONS WITHOUT PRIOR APPROVAL FROM FM RESEARCH.

5. THE ASSOCIATED APPARATUS MANUFACTURERS INSTALLATION INSTRUCTIONS MUST BE FOLLOWED WHEN

INSTALLING THIS EQUIPMENT.

©Copyright 2009 Dwyer Instruments, Inc.

DWYER INSTRUMENTS, INC.

Printed in U.S.A. 5/09

FR# 19-443480-00 Rev.2

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

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