Dwyer Instruments HM35 Installation and Operating Instructions

Operating instructions Digital handheld pressure gauge

HM35

Operating Instructions

Contents

Operating Elements .........................................................................................2

1 Description............................................................................................3

2 Safety information .................................................................................3

3 Operation .............................................................................................. 4

3.1 Switching on and off..............................................................................4

3.2 Lighting .................................................................................................5

3.3 Pneumatic connection........................................................................... 5

3.4 Functions and operating modes ............................................................6

3.5 Menu selection and set-up ....................................................................6

3.6 Data logging.......................................................................................... 9

3.6.1 Data recording ......................................................................................9

3.6.2 Transfer of data to a PC...................................................................... 10

3.6.3 Deleting data....................................................................................... 10

3.7 Communication...................................................................................10

3.7.1 IR/RS232-Protocol .............................................................................. 10

3.7.2 IR-Hardware of the instrument ............................................................12

3.8 Battery replacement............................................................................19

3.9 Calibration........................................................................................... 19

4 Specifications......................................................................................20

4.1 Technical data.....................................................................................20

4.2 Measuring Range and Precision ......................................................... 22

4.3 Measurement units .............................................................................23

4.4 Mains supply unit connection..............................................................24

5 Maintenance and storage ...................................................................24

6 Warning messages and faults............................................................. 24

7 Accessories ........................................................................................25

8 Summary of technical characteristics..................................................25

1

Operating Elements

Infra-red interface IR

Connection for pneumatic tube

Graphic display

Zero position / Exit menu

Function key

Select operating mode

Connection for 6 VDC power supply (not present in Ex-models)

Hold display

Start function

Switch On/Off (> 1 s: Light on)

Please note this warning symbol in these operating instruction s!

EC Declaration of Conformity

We declare on our own responsibility that this product conforms to the following standards:

• EN 61326-1/A1

2

1 Description

The HM35 digital pressure gauge is a pressure-measuring instrument with an integrated pressure sensor for the measurement of differential, relative or absolute pressures and vacuum. Its versatile range of functions and high precision render it suitable for a wide

range of applications. Via the infrared interface (IR) and SCPI (Standard Commands for Programmable Instruments) commands, the HM35 can communicate with a PC. Its

operation is very simple, and supports the user in his measurement tasks.

Operating modes

• Pressure measurement / Differential pressure

• Min./Max. values

• Mean value (average)

• Pressure change rate

• Data logging

Selectable configuration possibilities

• Data logging

Æ Interval time, print/transfer, deleted memory

• Configuration

Æ Measurement units, display filter, auto. switch-off time, auto zero, lighting level, etc.

• Average period (period for determining average value)

• Date and Time (real-time clock)

• Calibration

Æ Date of last calibration date, manual recalibration

2 Safety information

• The pressure values and overload levels stated on the rating plate and quoted in these operating instructions must not be exceeded, as otherwise the pressure sensor could be destroyed or there could be a risk of injury.

• Only use pressure hoses with a maximum loading capacity corresponding to that necessary for the application.

• Ensure that the pneumatic hoses are securely fitted! Do not use damaged or kinked hoses.

• Do not open up the instrument (this would void the guarantee).

• The instrument must be stored within the permissible storage temperature range.

The instrument must not be put into operation in an explosive environment!

Wear eye protection if working with pressures > 1bar!

3

3 Operation

3.1 Switching on and off

Switching on Briefly press the On/Off key ( ) (< 1 s)

For precise measurements, the HM35 must first be switched on for at least 1 minute (warm-up phase).

Switching off Briefly press the On/Off key

or automatic switch-off 3, 10 or 60 minutes after the last time key operation

(automatic switch-off does not take place during Average, Change Rate

and Data Logging measurements or in IR

Notes

• The HM35 switches on automatically when the supply voltage is connected.

• The HM35 continues to work in battery mode following an interruption of the supply

voltage

• In case of a change in temperature, the HM35 must be allowed to adapt to the new ambient temperature for a least 30 minutes while switched off in order to attain the best measurement accuracy.

• The day/time, battery level and accuracy will be briefly displayed at switch on:

• After switch-on, the HM35 switches to the last operational mode used, e.g.:

( ) (< 1 s),

and network operation).

• With the display filter activated, wait until the transient effect finishes (approx. 5 s).

4

3.2 Lighting

Switching on Press the On/Off-key

( ) for > 1 s

Brightness control In the Menu, select the Configuration → Lighting function and

select an adjustment of Off, Level 1, Level 2 or Level 3.

Switching off Briefly press the On/Off key

( ) (< 1 s)

(switch off the instrument), or automatic switch-off after 20 s.

With mains operation, the HM35 must be switched off manually.

3.3 Pneumatic connection

Designation Pressure range

Hose 4/6 mm

NPT1/8“ internal 10 ... 90 bar

Plug in nipple „Rectus“ Type 20

M10 x 1 internal thread (for „Minimess“ connector) all

≤ 7,5 bar

≤ 30 bar

Ensure that the pneumatic hoses are connected correctly! +P Higher pressure

S- Lower pressure (not available with the absolute and relative pressure version)

When screwing onto a coupling, it is important to hold the coupling steady with a wrench to prevent any turning!

Never secure by holding the casing itself!

5

3.4 Functions and operating modes

Key clear hold Functions

PRESSURE

DIFFERENCE

▲ MIN/MAX Sets Max/Min to

▼ AVERAGE 4)

CHANGE RATE 5) DATA LOGGING

Zero: sets measured value to

3)

zero

current measured value

Sets measured value to zero

3)

Freezes all

current

measurement

values

--

To Menu selection

1)

Stop/Menu

Start 2)

--

Starts measuring

Starts data logging

Notes

1) Once a measurement procedure has been started, the menu selection is blocked.

2) During a measurement procedure (after Start has been pressed), you can switch between functions. This permits, for example, the observation of the Min/Max function during data logging.

3) The Clear key has no function in the absolute pressure instruments.

4) The AVERAGE function creates an arithmetic average value of all measured values during the time period selected in the menu. After expiry of the time period, the average value will be displayed.

5) Measurement of the leak rate (diff/gauge sensor) or tendency (abs. sensor). The pressure change (CHANGE RATE) from the start time to the current time will be displayed. The first display occurs 10 s after the start.

3.5 Menu selection and set-up

Navigation within the Menu selection

clear

▲▼

Brief (< 1 s) 1 level back Long (> 1 s) Back to the function level/operating modes

Selection of Set-up/Functions

The functions shown inverted on the display will be carried out if the Function key

) is pressed.

( The currently selected setting for values is marked with '9'. In the following table, the default values are correspondingly marked (factory settings).

6

Key

Data logging

Interval Interval period

manual

25 M./s

10 M./s

1 s 9 2 s

5 s

10 s

30 s

1 min

2 min

5 min

10 min

30 min

1 h

3 h

6 h

12 h

24 h user Set with ▲/▼/ EDIT/OK

▲ Print Data Logging

▼ Press 'Start' Print/send via IR

Clear Memory

Press 'Clear' Deletes the data memory

Configuration

Pressure Unit 9 mbar

bar

Pa

hPa

kPa

MPa

kg/cm2

kg/m2

mmHg

cmHg

mHg

inHg

mmH2O

cmH2O

mH2O

inH2O

ftH2O

psi

lb/in2

lb/ft

torr atm

2

Notes

7 8

Key

Display Filter Filters the display values 1) 9 On Off

Auto-Off Auto. switch-off

3 min 9 10 min

60 min

Auto-Zero

On Sensor auto-zeros at switch-on

9 Off

Beep Warning beeper 9 On

Off

Lighting Off Level 1 Only Level 1 possible for Ex-models

Level 2

▲ 9 Level 3

▼ IR Interface

9 On At switch-on, the automatic

Off Automatic connection is de-activated

Average period Time period for average value

10 s

30 s

1 min

2 min 9 5 min

10 min

30 min

1 h

3 h

6 h

12 h

24 h user Set with ▲/▼/EDIT/OK

Date & Time dd.mm.yyyy Set with ▲/▼/ EDIT/OK hh:mm:ss Set with ▲/▼/ EDIT/OK

Calibration

History Displays the last calibration date

Manual re-calibration Manual re-calibration of the zero

Notes

if measured value < 1% FS

connection to the PC is activated for 2 minutes

point and limit value

Note

1) With the filter function active, short-term measurement variations should be suppressed, resulting in a steadier display. Measured values via the interface and in the Data Logging Memory will not be filtered.