Dwyer Instruments Love Series HM28 User manual

Operating instructions
Digital handheld
pressure gauge
HM28
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Contents
1 Description.......................................4
2 Safety details ...................................4
3 Operating .........................................4
3.1 Switching on and off ........................4
3.2 Pneumatic connection .....................4
3.3 Operating modes .............................4
3.4 Configuration ...................................6
3.5 RS 232 mode ...................................7
3.6 Battery change ..............................10
3.7 Recalibration..................................10
4 Specifications ................................10
4.1 Technical data ...............................10
4.2 Measuring ranges ..........................12
4.3 Mains supply unit connection ........12
5 Maintenance ..................................12
6 Warning messages and faults .......13
7 Accessories ...................................13
8 Calibration instructions ..................14
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ON = On
OFF = Off
MODE = Select operating mode
- Pressure measurement
- Min./Max.
- Leak rate
- Datalogging
CLEAR/ZERO = Zero setting
PRINT/HOLD = Print and freeze display
START/STOP = Data recording / printing
SET = Select config. modes
SELECT = Select config. data
cMatrix display
dConnection for pneumatic hoses
eConnection for plug-in power supply unit
fConnection for RS 232 interface
Important!
Please note warning symbol
in the operating instructions.
Copyright (c) by LOVE CONTROLS.
The contents of this publication may not be
copied without the express permission of
LOVE CONTROLS.
Subject to dimension and design changes.
Operating instructions
c
d
f
e
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1 Description
The „LOVE CONTROLS“ handheld pressure
gauge HM28 is a digital pressure measuring
instrument with integrated pressure sensor
for the measurement of differential, relative or
absolute pressures and vacuum. Its versatile
range of functions and high precision makes
it suitable for a wide range of applications.
Configuration possibilities:
• Autom. switching off, selectable time
• Selectable resolution and damping
• Selectable units of time
• Selectable measurement units
• General reset to standard setting
• Selectable data transfer rate
• Configuration printout
• Selectable measuring intervals
2 Safety details
The pressure values stated on the rating plate
and mentioned in these operating instructions
must not be exceeded otherwise the pressure
sensor can be destroyed.
Donotusetheinstrumentindanger
zones (explosives zones)!
Wear eye protection for pres-
sures > 1bar!
3 Operating
3.1 Switching on and off
Switching on Press the ON key (the maxi-
mum permissible measuring
range and the class appears
on the display).
For precision measurements
theinstrumentmustbe switch-
ed on for at least 1 minute
(warm-up phase).
Switching off Press the OFF key, or auto-
matic switching off 1,10 or 60
min after the last keystroke.
Incaseofa temperaturechangethe instrument
requires at least 30 minutes to adjust to the
new ambient temperature.
3.2 Pneumatic connection
For measuring ranges up to 7000 mbar, 4/6
mm or NPT 1/8" connectors can be connected
depending on model. Higher ranges are
equipped with NPT 1/8".
Ensure correct connection of the pneumatic
hoses!
+P high pressure
S- low pressure (not available
with the absolute and relative
pressure version)
Measuring negative differential or relative
pressures:
connect “S-” Înegative pressure,
or
change ports “S-“ and “+P”.
The HM28 will display a positive value.
When screwing on a coupling it
is important to hold with a span-
ner in the opposite direction.
Never hold at case only!
3.3 Operating modes
Themodes inthe matrixbelow canbe selected
in succession by pressing the MODE key.
After switching ON, the instrument is always
in the mode „normal“.
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Switching on
Normal
(differential)
and
analogue/hold
Normal
(absolute)
and differential
Zoom
Min/Max
Leak rate
Tendency
(absolute)
Record 1)
Print Record
print
hold
print
print
print
print
print
start/stop
print
quick keystroke:
max. output speed
Keystroke
approx.1s:
single or fast
output start/stop
printing
zero
display
zero
diff
zero
display
zero
(reset)
zero
display
clear
memory
Display example
Max. Range:
200 mbar
Full scale error
0.05 %
123.45 mbar
====== or
HLD 123.4 mbar
1013.2 mbar
DIF 1013.2 mbar
123.45
MAX 150.0 mbar
MIN 100.0 mbar
1234.5 mbar
LEK 2.1 /min
1013.2 mbar
TND - 15.7 /min
REC 432.1 mbar
STOP 30 s MEM 1
REC 432.1 mbar
RUN 30 s MEM 321
432.1 mbar
STOP 30 s MEM 901
PRINT RECORD
PUSH PRINT
PRT 432.1 mbar
321 00:13:30
PRT
Record stopped
Notes
Measuring range
displayed in desired
unit
Accuracy class as a %
of full scale reading
Only with differential
or relative pressure
models
Hold, store indicated
value
Only with absolute
pressure mode Zero
sets Diff to 0
Measurement in large
figures
With absolute pressure,
reset to actual value
Only with Diff./Rel.
(unit/time unit)
Only with absolute
pressure (unit/time unit)
If measurement
memory cleared
Recording runs up to
964 values
Recording stopped
Appears only if values
are stored
Printing / display with
time
Recording stopped
1) at 70 bar the measurements are stored in [bar]
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set unit mbar, kPa, bar, 2)
mmH2O, mH2O,
mmHg, psi, inH2O,
inHg, hPa, Pa, MPa
set high
resolution1) low
set damping off
on
set baudrate 9600, 4800, 2400,
1200
set auto-off 1, 10, 60 min
continuous continue
set time unit minutes
hours hours
set 1, 5, 10, 20, 30, 60 s
Rec. interval 2, 3, 5, 10, 30, 60 min
1) manual, off
set 2.5 Hz (400 ms)
display rate 5 Hz (200 ms)
general reset? set on default values zero
print print now
configuration?
UNIT
mbar
RESOLUTION Display resolution,
high influences measuring rate
in RS 232 mode
DAMPING 90% recovery after 4
off measurements (when ON)
BAUDRATE
9600
AUTO OFF Automatic switching off or
10 min continuous mode
TIME UNIT For leak rate, tendency
minutes
REC INTERVAL Off = record mode is
5 s (1.3h) deactivated
(max. record interval)
DISPLAY RATE Normal mode indication/zoom
2.5 Hz (400 ms) (influences DAMPING)
GENERAL RESET? Reset all settings and clear
PUSH ZERO measurement memory
GENERAL RESET? After actuating ZERO
RESET OK
PRINT CONFIG? Unit, ...
PUSH PRINT
PRINT CONFIG? After actuating PRINT
PRINTING
1) If changed, the measurement memory is cleared 2) See in 4.1 "Technical data"
Display example Notes
3.4 Configuration
Select mode:
Press >2 seconds Îon the display appears
CONFIGURATION
Store and exit:
Press >2 seconds Îon the display appears
SAVE CONFIGURATION
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Code Configuration
Pressure unitPressure unit
Pressure unitPressure unit
Pressure unit
5 MPa(7-70bar)
6 Pa(25mbar-7bar)
7 kPa
8 bar
9 mH2O(with 70bar,
otherwise mmH2O)
10 mmHg(not with
70bar)
11 psi
12 inH2O
13 inHg (not with
70bar)
14 hPa
15 mbar
ResolutionResolution
ResolutionResolution
Resolution
0 low
1 high
DampingDamping
DampingDamping
Damping
0on
1 off
BaudrateBaudrate
BaudrateBaudrate
Baudrate
0 1200 Baud
1 2400 Baud
2 4800 Baud
3 9600 Baud
Code Configuration
Switch. off timeSwitch. off time
Switch. off timeSwitch. off time
Switch. off time
0 60 min
1 continous
2 1 min
3 10 min
Time unitTime unit
Time unitTime unit
Time unit
0 /hours
1 /minutes
Storage intervalStorage interval
Storage intervalStorage interval
Storage interval
2 10 s
3 20 s
4 30 s
5 60 s
6 2 min
7 3 min
8 5 min
9 10 min
10 30 min
11 60 min
12 manual
13 off
14 1 s
15 5 s
Display rateDisplay rate
Display rateDisplay rate
Display rate
0 5 Hz
1 2.5 Hz
Reply to control command «readconfig»
A whole number is returned as a reply
msb lsb
#### #### #### ####
|||| |||| |||| ****- Pressure unit
|||| |||| |||*------ Resolution
|||| |||| ||*------- Damping
|||| |||| **-------- Baudrate
|||| ||**----------- Switching off time
|||| |*------------- Time unit
|***-*-------------- Storage interval
*------------------- Display rate
3.5 RS 232 mode
The HM28 can be remotely operated from a
personal computer via an RS 232 interface.
The automatic switching off (chapter 3.1) is
inactive. Connection by means of a RS232-
cable.
PlugpinassignmentRS232,DB 9(female)
Pin Assignment Pin Assignment
1 DCD 6 DSR
2 TXD 7 RTS
3 RXD 8 CTS
4 DTR 9 SHIELD
5 GND
Protocol
ASCII-commands
9600/4800/2400/1200 baud, 8 bit, no parity,
1 stop bit,
XON/XOFF - protocol (17 dec/19 dec)
Notes
- The HM28 is switched on when the
supply voltage is applied
- The HM28 sends "XON" every 3 seconds
To determine the baud rate, read-in
"XON" in each transfer rate until "XON"
is correctly identified
- To go to remote control mode, interrogate
"XON", immediately send the "remote"
command and then read-in the
acknowledgement "ok"
- Only lower case letters are accepted
- Observe > 0,1 s delay before the next
command after "setbaud" command
- To acknowledge the answer of the HM28
without reading it back, just send a "XON"
- The symbol "*" followed by the checksum
must be suffixed to each string. The string
must be terminated with a CR
- A "TAB" is prefixed to each answer of the
HM28, a "*" suffixed and the checksum
sent.
The answer is terminated with a CR
- The checksum is formed from the least
significant byte of the command string
Code-decoding of control command
«readconfig»
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remote * 182 CR (tab)[ok] * 13 CR Switch to remote control and
block keypad
local * 53 CR (tab)[ok] * 13 CR Switch to keypad off * 101 CR (tab)[ok] * 13 CR Switch off instrument readpress * 243 CR (tab)"Value" _ "Unit" * Checksum CR Interrogate measurement readpressfast * 161 CR (tab)"Value" * Checksum CR (tab)"Value" * Checksum CR Fast measurement interrogation
"RESOLUTION high" output10 M/s "RESOLUTION low" output 20 M/s
$ (tab)[ok] * 13 CR Exit "readpressfast" mode
following send "XON"
readrange * 211 CR (tab)"Range" _ "Unit" * Checksum CR Interrogate measuring range readbat * 253 CR (tab)"full"/"empty" * 230/98 CR Interrogate battery capacity (lobat)
(full=ok, empty=change)
readrecord * 69 CR (tab)"Recinterval" _ (tab)"Value" _ (tab)"Value" _ (tab)"Value" Interrogate stored measured
(tab)[record_stopped] * 200 CR Recording is stopped (tab)[out_of_range] * 164 CR Measurement out of range (tab)[record_end] * 0 CR Recording stopped (waits at "XON"
and sends back "ok" )
readtemp * 124 CR (tab)"Value" _ °C * Checksum CR Interrogate internal temperature,
±4°C (±39 °F)
clearmem * 112 CR (tab)[ok] * 13 CR Clear datalogging memory readconfig * 60 CR (tab)Code (see decoding in table page 17) * Checksum CR Readout actual configuration setzero * 54 CR (tab)[ok] * 13 CR Zero indication setdefault * 91 CR (tab)[ok] * 13 CR Reset all settings and clear memory,
change to keypad
setunit_kpa * 146 CR (tab)[ok] * 13 CR Corresponding units setunit_mbar * 248 see 4.1 Technical data setunit_bar * 139
Control commands/syntax Answer from HM28/syntax Description
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setunit_mmh2o * 57 setunit_mmhg * 255 setunit_psi * 162 setunit_inh2o * 54 setunit_inhg * 252 setunit_hpa * 143 setunit_pa * 39 setunit_mpa * 148 setbaud_9600 * 1 CR (tab)[ok] * 13 CR Select baud rate (answer with setbaud_4800 * 254 new baud rate, wait >0,1s setbaud_2400 * 248 before "XON") setbaud_1200 * 245 resolution_high * 62 CR (tab)[ok] * 13 CR Select measurement resolution resolution_low * 240 and indication, high:10 M/s,
low: 20 M/s
settempmode_0 * 33 CR (tab)[ok] * 13 CR Temp. measuring will be switched
off at RS232 mode
settempmode_1 * 34 Temp. measuring will be done
periodically (default value)
setrecint_off * 86 CR (tab)ok * 13 CR Select storage interval (secondes) setrecint_man * 87 (tab)ok setrecint_1 * 76 (tab)ok setrecint_5 * 80 (tab)ok setrecint_10 * 124 (tab)ok setrecint_20 * 125 (tab)ok setrecint_30 * 126 (tab)ok setrecint_60 * 129 (tab)ok setrecint_2m * 186 (tab)ok Select storage interval (minutes) setrecint_3m * 187 (tab)ok setrecint_5m * 189 (tab)ok setrecint_10m * 233 (tab)ok
Control commands/syntax Answer from HM28/syntax Description
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setrecint_30m * 235 CR (tab)ok * 13 CR setrecint_60m * 238 (tab)ok setautooff_man * 198 CR (tab)ok * 13 CR Select autom. switching off time (minutes) setautooff_1 * 187 (tab)ok setautooff_10 * 235 (tab)ok setautooff_60 * 240 (tab)ok setdamp_off * 115 CR (tab)ok * 13 CR Damping off setdamp_on * 21 (tab)ok Damping on setdisrate_2.5 * 23 CR (tab)ok * 13 CR Set display rate (Hz) setdisrate_5 * 183 (tab)ok setunit_perh * 5 CR (tab)ok * 13 CR Tendency .../h setunit_permin * 225 (tab)ok Tendency .../min
(tab)[er] * 10 CR Error
Control commands/syntax Answer from HM28/syntax Description
Note: The character _ indicates a space
3.6 Battery change
- Open battery receptacle
- Insert 9 V-alkali battery (IEC 6LR61) or
accumulator
Ensure correct polarity!
Correct disposel of the used
batteries according to environment
regulations!
3.7 Recalibration
Recalibration to be carried out by specially
skilled staff only.
Relevant instructions see in section 8. We
recommend to recalibrate the instrument at
least once a year.
4 Specifications
4.1 Technical data
Measuring media instrument air or
inert gases
Media-compatible all media compatible
types with stainless steel
18/8 (DIN 1.4305)
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