Dwyer Instruments DHII-008, DHII-009, DHII-007, DHII-010, DHII-004 User manual

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Bulletin B-31

Series DHII Digihelic®II Differential Pressure Controller

Specifications - Installation and Operating Instructions

DWYER INSTRUMENTS, INC.

P.O. BOX 373 • MICHIGAN CITY, IN 46360, U.S.A. Fax: 219/872-9057 e-mail: info@dwyer-inst.com

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

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DIMENSIONS

1-1/2

[38.35]

1-45/64 [43.18]

2-23/64 [59.94]

-31/64

[37.62]

4-23/32

[

120]

4-23/32

[120]

-7/16

[

87.12]

1-5/16

[33]

1-17/32 [

38.61]

45/64

[17.78]

1-1/16

[26.97]

1-7/8

[47.5]

1-45/64 [43.18]

MOUNTING HOLE

PATT ERN

4X Ø3/16 [4.76]

CLEARANCE HOLES FOR

MOUNTING

3-17/64

[83]

4-1/8 [105]

5-7/32

[132.56]

4-9/64

[105.17]

#8 LOCK WASHER

8-36 FLAT HEAD SCREWS

O NOT REMOVE

THESE SCREWS

TO GAIN ACCESS TO WIRING TERMINALS,

REMOVE THESE TWO SCREWS AND “FLIP” DISPLAY

90° DO NOT REMOVE THE SCREWS WITH]

POWER APPLIED TO INSTRUMENT

HINGED

STANDO FF

WIRING

TERMINALS

OPTIONAL A-438 BRACKET MOUNTING DIAGRAM

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WIRING TERMINAL ACCESS

SPECIFICATIONS Service: Air and non-combustible, compatible gases. Wetted Materials: Consult factory. Housing Material: 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:

High Voltage Power = 100 to 240 VAC, 50 to 400 Hz or 132 to 240 VDC; Low Voltage Power = 24 VDC ±20%.

Power Consumption:

Low Voltage Power = 24 VDC - 130 mA max. High Voltage Power = 100 to 240 VAC, 132 to 240 VDC - 7VA max.

Output Signal: 4-20 mA DC into 900 ohms max. Zero & Span Adjustments: Accessible via menus. Response Time: 250 ms (dampening set to 1). Display: 4 digit backlit LCD 0.6˝ height. LED indicators for set point and alarm status. Electrical Connections: Euro type removeable terminal blocks with watertight conduit fittings for

1/2˝ watertight conduit.

Process Connections: 1/8 female NPT. Enclosure Rating: Designed to meet NEMA 4 (IP66). Mounting Orientation: Mount unit in vertical 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). Serial Communications: Modbus®RTU, RS485, 9600 Baud. Agency Approvals: UL & CE.

SWITCH SPECIFICATIONS Switch Type: 2 SPDT relays. Electrical Rating: 8 Amps at 240 VAC resistive. Set Point Adjustment: Adjustable via keypad on face.

Modbus®is a registered trademark of Schnieder Automation.

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WIRING

11 22 33 44

3 44 55 66

CONNECTORCONNECTOR ONON LOWERLOWER BOARDBOARD

ONNECTORCONNECTOR ONON

UPPERUPPER BOARDBOARD

100-240100-240 VACVAC oror 1

32-240132-240 VDCVDC POWERPOWER

NOTENOTE 11

3/83/8 AA 250vac250vac M

EDIUMMEDIUM LAGLAG

/CN/C

N/CN/C

N/ON/O

SP1SP1 RELAYRELAY

SP2SP2 OROR ALARMALARM R

ELAYRELAY

A-A- B

+B+

S485RS485 SERIALSERIAL

COMMUNICATIONCOMMUNICATION

2424 VDCVDC POWERPOWER NOTENOTE 11

EMOTEREMOTE RESETRESET

WITCHSWITCH

DeviceDevice receivingreceiving 4-20mA4-20mA signal.signal. CheckCheck specicationsspecications o

fof thisthis devicedevice forfor inputinput loadload

esistance.resistance. TypicalTypical 250250 toto 600600 OHMS,OHMS, 900900 OHMSOHMS maximum.maximum.

4-20mA4-20mA TRANSMITTERTRANSMITTER OUTPUTOUTPUT



Notes:

WARNING

If Digihelic®II Controller is powered by 24 VDC, the device receiving the 4-20 mA transmitter output MUST NOT share a common ground with the 24 VDC supply or damage to the Digihelic®II Controller will result.

1. The instrument may be powered from the AC line or 24 VDC. Do not wire AC line terminals 1-2 on the lower board and 24 VDC terminals 4-5 on the upper board at the same time or damage to the unit will result.

2. For supply connections, wire in accordance with an equivalent national standard or code. Use copper conductors only rated for at least 75°C.

3. Terminals on upper board are rated CLASS 2.

4. ISOLATION:

Relays - 1500 VAC to all other inputs and outputs. AC Line Power (terminals 4-5) - 1500 VAC to all other inputs and outputs. RS485 output - 500 VAC to all other CLASS 2 wiring. The 24 VDC Power, 4-20 mA transmitter, and Remote Reset Switch share a common ground.

5. The Remote Reset Switch must be a dry contact switch.

6. Shielded cable is required for RS485 wiring.

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When wiring the instrument, you must follow industry standard practice for control and

SHIELDSHIELD

TIETIE SHIELDSHIELD TOTO EAR THEARTH GROUNDGROUND

TOTO RS232RS232 TOTO RS485RS485 CONVERTERCONVERTER

120120 OHMOHM RESISTORRESISTOR

ASTLAST UNITUNIT ONON RS485RS485 BUSSBUSS

WIREWIRE NUTNUT

DIGIHELICDIGIHELIC -- RS485RS485 WIRINGWIRING TOTO DAISYDAISY CHAINCHAIN INSTRUMENTSINSTRUMENTS ONON THETHE RS485RS485 BUSSBUSS UPUP TOTO 128128 UNITSUNITS MAYMAY BEBE DAISYDAISY CHAINEDCHAINED

THETHE 120120 OHMOHM RESISTORRESISTOR ISIS USUALLYUSUALLY ONLYONLY NECESSARYNECESSARY FORFOR LONGLONG WIREWIRE RUNS.RUNS.

1 22 33 44

3 44 55 66

CONNECTORCONNECTOR ONON LOWERLOWER BOARDBOARD

CONNECTORCONNECTOR ONON U

PPERUPPER BOARDBOARD

11 22 33 44

33 44 55 66

CONNECTORCONNECTOR ONON LOWERLOWER BOARDBOARD

CONNECTORCONNECTOR ONON U

PPERUPPER BOARDBOARD

1 22 33 44

3 44 55 66

CONNECTORCONNECTOR ONON LOWERLOWER BOARDBOARD

CONNECTORCONNECTOR ONON U

PPERUPPER BOARDBOARD

protection against Electro-Static Discharge (ESD). Failure to exercise good ESD practices

꟣

may cause damage to the control.

WIRING

1. Remove cover.

2. To gain access to the wiring terminal blocks, remove the upper and lower screws toward the center of the display board, and then flip the display board up at a 90° angle.

3. Wire to the two terminals blocks as shown in the wiring diagram.

Note: Depending on the application, it may be only necessary to wire to the smaller terminal block on the upper board. In that case one of the liquid tight fittings may be removed and replaced with the provided rubber plug.

4. For liquid tight applications, use only 1/2˝ liquid tight conduit.

5. When wiring is complete, reverse steps 2 and 1. Make sure the cover is properly tightened to the housing.

DIGIHELIC® II CONTROLLER RS485 WIRING

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 Digihelic with a 1/2˝ wrench to prevent the fitting on the Digihelic®II Controller from turning.

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II Controller

SP/ALSP/AL

ENUMENU

RSTRST

KEY FUNCTIONS

SP1SP1

SP2SP2

LHIALHI

LLOALLO

SCFMSCFM

99.9999.99

X1K

P/ALSP/AL

RSTRST

MENUMENU

MULTIPLIERMULTI P L IE R DESCRIPTORDESCRIPTOR VISIBLEVISIBLE WITHWITH SOMESOME VELOCIT YVELOCIT Y ANDAND FLOWFLOW RANGESRANGES

FRONTFRONT PANELPANEL

UNITSUNITS

PROCESSPROCESS VALUEVALUE

HIGHHIGH ALARMALARM DESCRIPTORDESCRIPTOR

LOWLOW ALARMALARM DESCRIPTORDESCRIPTOR

P1SP1

DESCRIPTORDESCRIPTOR

SP2SP2 DESCRIPTORDESCRIPTOR

HOME POSITION FUNCTION

Sequences the display

SP/AL

through SET POINT and ALARM settings Allows access to the menus

ARROW

Displays full scale range of

ENTER

RESET

unit

Clears or resets an Alarm (alarm set for manual reset)

MAIN MENU FUNCTION

Return to home position

Sequences through menus

Enter into SUB MENU

SUB MENU FUNCTION

Return to home position

Return to previous menu

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.

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SETTING SET POINTS AND ALARMS

P/ALSP/AL

SP/ALSP/AL SP/ALSP/AL

P/ALSP/AL

SP/ALSP/AL

SP/ALSP/AL SP/ALSP/AL

SP/ALSP/AL

P/ALSP/AL

Visible whenVisible when

mode =mode =

CONTROL MODECONTROL MODE

PRES

SURE

PRESSURE

TIMETIME

0.20.2

0.40.4

0.60.6

0.80.8

1.0

(in. w.c.)

SP/ALSP/AL

The hot key provides direct access to the Set Point and Alarm MENU. The Set Point and Alarm MENUS that are displayed are based upon the Control (CtrL) SUB MENU.

SET POINT ADJUSTMENT

Adjusting the Digihelic®II Controller Set Points is quick and simple. Instead of setting a set point and deadband, simply adjust SP 1 H or SP 2 H for the desired relay turn on point, and then adjust SP 1 L or SP 2 L for the desired relay turn off point.

In the above graph, an instrument with a 1.0˝ range would have the SP1 relay turn on at 0.8˝ and off at 0.4˝. S P 1H sets the relay turn on point, and SP1L sets the relay turn off point. The relays outputs normally function in the direct acting mode, which means the relays turn on with an increase in pressure. SP1 may be configured to act as a reverse acting relay (refer to the 1SP SUB MENU setting, page 15). When set for reverse acting, S P 1 H sets the relay turn OFF point, and S P 1 L sets the relay turn ON point. SP2 is always direct acting.

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MENU MAPMENU MAP

CONTINUED

SETTINGSSETTINGS

MAIN MENUS SUB MENUS

MENUS

UNAVAILABLE

FOR

BI-DIRECTIONAL

RANGES AND

RANGES ABOVE

25 IN. W.C.

MENUMENU

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CONTINUEDCONTINUED

SETTINGSSETTINGS

MAIN MENUS SUB MENUS

MENUMENU

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MAIN MENUS SUB MENUS

SETTINGS

MENUMENU

Menus present only

in pressure operation

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Main Menu Selections (Upper Right Display Reads MENU )

SECr Security - Lock out access to Set Point and Alarm settings, or lock out access to all

settings.

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

OUt Output - Select a Single Set Point, 2 Set Points, or a Set Point and an Alarm mode of

operation.

d.S Display - Monitor and adjust display related settings: Peak, Valley, display resolution, %

output and dampening.

AdU Advanced functions - Modify advanced function parameters, transmitter output scaling,

Modbus®communication settings, Maintenance Set Point settings and calibration.

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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 Menu Access

Password Value to Enter

10 70

SP/AL Locked

SP/AL Access

Menus Locked

All settings locked

111

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 O P E r MENU selects the measurement type of the instrument. The SUB MENUS are:

PrES - Pressure KFAC - K Factor XDIM - X Dimension UEL - Velocity ArEA - Area YDIM - Y Dimension FLO - Flow DIA - Diameter

If the instrument is set for Velocity, the O P Er MENU will have an additional KF A C SUB MENU. If the instrument is set for Flow, the OPE r MENU will have additional KFAC and A r E A 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 show the units in the upper right display. The other measurement types will have a blank upper right display.

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PrES (Pressure) SUB MENU

For pressure measurement, the following units are available:

INWC - I nches o f w at er co lu mn FTWC - F eet o f wat er co lu mn MMWC - M illimeter s of water column CMWC - C entimeter s of water c olumn PSI - P ou nds p er sq ua re in ch INHG - I nches o f m er cu ry

Table 1 Pressure Range vs. Available Units

INWC

FTWC

MMWC

.1000 .2500 .5000

1.000

2.500

5.000

10.00

25.00

50.00

100.0

Note: O V F L (over flow) or UnFL(under flow) will appear when the ranges have been exceeded above or below full scale by 2%.

UEL (Velocity) SUB MENU

For velocity measurement, the following units are available:

.2083 .4167 .8333

2.083

4.167

8.333

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

PSI

.1806 .3613 .9032

1.806

3.613

INHG

.1839 .3678 .7356

1.839

3.678

7.356

MMHG - M illimeter s of mercury MBAR - M illibar PA - P as ca l KPA - K il opascals HPA - H ec topascals OZIN - O unce in ches

MBAR

.2491 .6227

1.245

2.491

6.227

12.45

24.91

62.27

124.5

249.1

24.91

62.27

124.5

249.1

622.7 1245 2491 6227

.1245 .2491 .6227

1.245

2.491

6.227

12.45

24.91

MMHG

.1868 .4671 .9342

1.868

4.671

9.342

18.68

46.71

93.42

186.8

KPA

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

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

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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 Maximum Duct Size (English)

RANGE IN WC

0.1

0.25

0.5 1

2.5 5 10 25

Table 5 FLOr = LO Maximum Duct Size (Metric)

RANGE IN WC

0.1

0.25

0.5 1

2.5 5 10 25

SCFM RANGE

99.99 x 1K

Mˆ3/Hr RANGE

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

MAX. DUCT SIZE Mˆ2

4.32

2.73

1.93

1.37

0.86

0.61

0.43

0.27

Table 4 FLOr = HI Maximum Duct Size (English)

RANGE IN WC

0.1

0.25

0.5 1

2.5 5 10 25

Table 6 FLOr = HI Maximum Duct Size (Metric)

RANGE IN WC

0.1

0.25

0.5 1

2.5 5 10 25

SCFM RANGE

999.9 x 1K

Mˆ3/Hr Range

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

MAX. DUCT SIZE, Mˆ2

43.19

27.31

19.3

13.64

8.63

6.10

4.31

2.73

KFAC

When the Digihelic®II Controller is used with a pitot tube, the manufacturer may specific a K Factor. The adjustment range is 0.01 to 2.00. The factory setting is 1.

SUB MENU

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

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ArEA, D I A , X D I M and YDIM SUB MENUS

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 F L O r = L O and 0.1 foot resolution for F LOr = H I , or entered in millimeters with

1 millimeter resolution.

ArEA - Area, select CI R for a circular duct or R E C T for a rectangular duct. If a circular duct is selected, the DIA SUB MENU will be activated. If a rectangular duct is selected, the XDIM and Y D I M SUB MENUS will be activated.

DIA - Diameter, enter the diameter of a duct XDIM - Enter the “X” dimension of a duct YDIM - Enter the “Y” dimension of a duct

OUt (Output) MAIN MENU

The O U t MENU selects the output type of the instrument. The SUB MENUS are:

CtrL- Control type ALrE - Alarm reset, manual or auto ISP - SP1 reverse or direct acting AL.H - Alarm inhibit AL - Alarm type ALDL - Alarm delay

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100

Process

verse

Act

Tim

SPH

SPL

Relay Inactive

Relay Active

CtrL (Control) SUB MENU

100

Process

Dire

Act

SPH

SPL

Relay Inactive

Relay Active

1SP - Single set point 2SP - Two fully independent set points SPAL - Single set point and alarm

1SP (SP1 Reverse or Direct Acting) SUB MENU

DIR - Direct. Relay turns on with increasing pressure REV - Reverse. Relay turns on with decreasing pressure

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The following alarm function SUB MENUS are activated when

MIN. PRESSURE

MAX. PRESSURE

ALHI

Relay OFF Relay ON

HIGH AL AR M FUNCTION

MIN. PRESSURE

MAX. PRESSURE

ALLO

Relay ON Relay OFF

LOW ALA RM F UN CTION

MIN. PRESSURE

MAX. PRESSURE

ALLO

Relay ON Relay OFF Relay ON

HIGH/L OW AL ARM

FUNCTION

ALHI

(Alarm Type) SUB MENU

- High alarm

- Low alarm

HILO

- For a high/low guardband type alarm

ALARM ADJUSTMENT

Alarm settings are dependent upon the selected alarm mode. The Digihelic®II Controller alarm may be configured as a High Alarm, Low Alarm, or High/Low Alarm. Alarm settings are all absolute and may be set to anywhere within the range of the instrument. The dead bands of the alarms are fixed at 1% of full scale.

CtrL

is set to

SPAL

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ALrE (Alarm Reset) SUB MENU

ONOF- Automatic reset HOLD - Manual reset. An alarm is reset by the RESET key on the front panel, or an external

reset switch.

AL.H (Low Alarm Inhibit) SUB MENU

ON - Alarm inhibit is on OFF - Alarm inhibit is off

If A L . H is selected ON, a low alarm condition is suspended upon power up until the process value passes through the alarm set point once.

ALDL (Alarm Delay) SUB MENU

Sets the amount of time an alarm condition must be continuously met before the alarm condition is recognized. The alarm delay is adjustable from 0-3600 seconds.

d.S (Display) MAIN MENU

PEAK - Peak value rESO - Resolution VALy - Valley value Pd. S - Process display ZERO - Zero 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 PEAK is reset to the present pressure reading. To manually reset the P E A K value, press the RESET key while in the P E A K 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 V A L y is reset to the present pressure reading. To manually reset the VALy value, press the RESET key while in the V A Ly SUB MENU.

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rESO (Resolution) SUB MENU

The Digihelic®II 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 (3DIG) can only be active when there is at least one digit to 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

When the display is reading percent, P C T is displayed in the upper right of the 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 A DDR - Modbus® address POH - Process output high WR - Modbus®write enable/disable MSP1 - Maintenance set point 1 ZERO - Zero calibration MSP2 - Maintenance set point 2 SPAN - Span calibration

POL and P OH (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 PO L to the desired display reading for 4mA output, and set P O H to the desired display reading for 20 mA output.

POH must be higher than POL. P O L may be adjusted 2% BELOW minimum scale up to P O H. POH may be adjusted from POL to 2% ABOVE maximum scale.

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MSP1 and MSP2 (Maintenance Set Point 1 & 2) SUB MENUS

SP/ALSP/AL

Adjust for the desired maintenance set points when the unit is placed in the maintenance mode. The deadband is fixed at 2% of full scale. To enter or leave the maintenance mode, press and hold the for 8 seconds.

ADDR (Modbus® Address ) SUB MENU

Modbus®communication instrument address. Set from 1 to 247. This number must match the address number used by the host computer. To obtain the Digihelic®II Controller Modbus®register list please visit www.dwyer-inst.com See page 4 for wiring diagram.

WR (Modbus® Write Protect) SUB MENU

d.S - Disables write commands from Modbus®. Modbus®can only read information from the

instrument.

En - Enable write commands from Modbus®. Modbus®can read information from and write

information to the instrument.

ZERO and SPAN (Calibration of Zero and Span) SUB MENUS

The lower display reads CAL in this mode.

ZERO Calibration

Note: For accurate calibration, DO NOT apply any pressure when performing this function.

With the display reading ZERO , press the ENTER key. The upper display will blink. Press ENTER again to complete the zeroing of the instrument or press the ME N U key to cancel.

SPAN Calibration

With the display set to S P A N , apply full scale pressure to the unit. Press the ENTER key. The upper display will blink. Press ENTER again to complete the calibration or press the M E N U key to cancel.

DWYER INSTRUMENTS, INC.

P.O. BOX 373 • MICHIGAN CITY, IN 46360, U.S.A. Fax: 219/872-9057 e-mail: info@dwyer-inst.com

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Printed in U.S.A. 10/13

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

FR# 19-443434-00 Rev. 3

Dwyer Instruments DHII-008, DHII-009, DHII-007, DHII-010, DHII-004 User manual

Specifications and Main Features

Frequently Asked Questions

User Manual