GHM DeltaOHM HD2301.0 User manual

Operating manual
Thermohygrometer
HD2
301.0
www.deltaohm.com
English
Ke ep for future refer ence.

HD2301 - 2 - V1.7
CON TEN TS
GENERAL CHARACTERI STI CS ......................................................................... 3
DESCRI PTI ON OF TH E FUN CTI ON S ................................................................. 6
TH E PROGRAM MI N G M EN U ............................................................................. 9
PROBES AN D MEASUREMEN TS...................................................................... 1 0
MEASUREMENT OF RELATI VE HUMI DI TY................................................................. 10
PERFORMI NG THE MEASUREMENT ........................................................................ 10
CALI BRATI ON OF THE COMBI NED HUMI DI TY/TEMPERATURE PROBE ................................. 11
DI RECT I NPUT I NTO Pt 100 AND Pt 1000 TEMPERATURE PROBES ..................................... 13
TEMPERATURE MEASUREMENT............................................................................ 13
CONNECTI NG THE TP47 CONNECTOR FOR THE 4- WI RE Pt100 AND 2OR 4 - WI RE Pt1000
PROBES ......................................................................................................13
DI RECT CONNECTI ON OF 4WI RE Pt100 SENSORS ................................................... 15
W ARN I N GS .................................................................................................. 1 6
I N STRU M EN T SI GNALS AN D FAULTS ............................................................ 1 7
LOW BATTERY W ARN I N G AN D BATTERY REPLACEM EN T ............................... 1 8
WARNI NG ABOUT BATTERY USE ............................................................................. 18
I N STRU M EN T STORAGE ................................................................................ 1 9
NOTES ABOUT W ORKI N G AN D OPERATI V E SAFETY................................................. 2 0
TECH N I CAL CH ARACTERI STI CS .................................................................... 2 1
TECHNI CAL I NFORMATI ON ON THE THERMOHYGROMETER............................................... 21
TECHNI CAL DATA OF PROBES AND MODULES I N LI NE WI TH THE I NSTRUMENT........................ 22
TEMPERATURE PROBES Pt 100 SENSOR USI NG SI CRAM MODULE.................................. 22
Pt100/ Pt1000 PROBES WI TH TP47 CONNECTOR WI THOUT SI CRAM MODULE .................22
RELATI VE HUMI DI TY AND TEMPERATURE PROBES USI NG SI CRAM MODULE.........................23
ORD ERI N G COD ES ........................................................................................ 2 4

HD2301 - 3 - V1.7
GEN ERAL CH ARACTERI STI CS
The Therm ohygrom eter Model H D 2 3 0 1 .0 is a port able inst rum ent that m easures an
environm ent's t em perat ure and relat ive hum idit y.
I t is fit t ed wit h a large LCD display for ex cellent visualizat ion of t he m easured dat a.
The Therm ohygrom eter Model H D2 3 0 1 .0 m easures:
•relat ive hum idit y and t em perat ur e using com bined pr obes, fit t ed w it h a Pt 100
tem perat ure sensor or t herm ocouple;
•t em perat ure only by im m ersion, penet rat ion, or contact probes. The sensor
can be a Pt100 or Pt 1000.
When t he com bined hum idit y/ t em perat ure probe is connect ed, t he inst rum ent
calculates and displays t he follow ing data:
•absolut e hum idit y,
•dew point ,
•part ial vapour pressure.
The probes are fitt ed with t he autom at ic det ect ion SI CRAM m odule, wit h t he fact ory
calibrat ion set t ings already being m em orized inside.
The unit s of m easurem ent are t he following:
1. % RH % of relat ive hum idit y
2. g/ m 3Gram s of vapour in a cubic m eter of dry air
3. hPa Part ial vapour pressure ( hPa)
4. Td Dew point ( ° C or ° F)
5. ° C/ ° F Tem perature in Celsius ( ° C) or Fahreneit ( ° F) degrees.
Using t he Max, Min and Avg funct ion of t his inst rum ent respect ively obt ains t he
m axim um , m inim um or average values.
Ot her available funct ions are:
•t he r elat ive m easurem ent REL;
•the HOLD function;
•the autom atic t urning off which can also be disabled.
For furt her details see chapt er ‘Descript ion of the funct ions’ at page 6.

HD2301 - 4 - V1.7
Therm ohygrom eter
H D 2 3 0 1.0

HD2301 - 5 - V1.7
HD 2 3 0 1 .0
1. I nput for probes, 8-pole DI N45326 connector.
2. Bat tery sym bol: displays t he bat tery charge level.
3. Function indicators.
4. Secondary t em perat ure display line.
5. D ATA/ EN TER key: during norm al operat ion displays t he m ax im um ( MAX) , t he
m inim um ( MI N) and t he average ( AVG) of current m easurem ents; in t he m enu,
confirm s t he current select ion.
6. CLR/ ESC key: during norm al operat ion r esets t he m axim um , t he m inim um and
t he average of current m easurem ent s; in t he m enu, it reset s t he value set with t he
arrows.
7. H OLD/ key : freezes t he m easur em ent display during nor m al oper at ion; in t he
m enu, increases t he current value.
8. U N I T/ MEN U key : it allows select ion of t he unit of m easur em ent ; w hen pressed
together wit h the DATA key, it allows t o open t he m enu.
9. REL/ key : during nor m al operat ion enables t he r elat ive m easurem ent ( displays
the difference between the current value and the logged value when t he key is
pressed) ; in t he m enu, decreases t he current value.
10.ON -OFF/ AUTO-OFF key: t urns the instrum ent on and off; when pressed t ogether
wit h t he HOLD key, disables t he AutoPowerOff funct ion.
11.MAX ( m axim um v alue) , MI N ( m inim um v alue) and AV G ( aver age value) sym bols.
12.Main display line of r elat iv e hum idit y and ot her der ived m easurem ent s.
13.Line for sym bols and com m ent s.

HD2301 - 6 - V1.7
DESCRI PTI ON OF TH E FUN CTI ON S
The keyboard of the therm ohygrom eter HD 2 3 0 1 .0 is com posed of double-funct ion
keys. The function on t he key is the "m ain function", while t he one above the key is
the "secondary function".
When t he inst rum ent is in st andard m easurem ent m ode, t he m ain funct ion is act ive.
I n t he m enu, the secondary funct ion is enabled; press the D ATA+ UN I T keys toget her
t o open t he m enu.
The pressing of a k ey is accom panied by a short confirm at ion " beep" : a longer " beep"
sounds if the wrong key is pressed. Each key specific funct ion is described in det ail
below.
This key has two functions:
•ON / OFF: press t his key to turn t he inst rum ent on and off.
The t urning on enables all display segm ents for a few seconds, st ar ts an Au t o-t est
including the det ect ion of t he probe connect ed t o the input, and sets the inst rum ent
ready for norm al m easurem ent .
MIN
cm
min s
2
3
m
µ
m
k
>>>
•AUTO/ OFF: the Au t oPow e r Off funct ion can be disabled by sim ult aneously
pressing this key and the "HOLD" key when t urning t he inst rum ent on.
During t urning on, should no probes be connect ed, the "N O_ PRBE_ SER_ N UM"
m essage is displayed in t he line for sym bols for a few seconds, and in t he m ain line a
series of dashes appears while t he "ERR" m essage replaces t he tem perat ure.
When t he probe is inserted int o a funct ioning inst rum ent , t he " NEW _ PROB_ DET"
( New pr obe det ect ed) m essage appears: as t he dat a are captur ed upon t ur ning t he
inst rum ent on, it is necessary to turn it off and on again.
Caution! Replace the probes when the inst rum ent is off.
ON - OFF a nd AUTO- OFF

HD2301 - 7 - V1.7
The inst rum ent has an AutoPowerOff funct ion t hat aut om at ically turns t he inst rum ent
off aft er about 8 m inutes if no key is pressed during the intervening t im e.
Press sim ult aneously the ON / OFF key and the HOLD key t o disable t h is f unct ion.
I n this case, rem em ber t o t urn t he inst rum ent off using t he ON / OFF key: disabling of
t he aut om at ic turning off is shown by the blinking bat tery sym bol.
The CLR key has t wo funct ions:
•CLEAR ( CLR) : allows t o reset t he m axim um ( MAX) , m inim um ( MI N) and average
( AVG) value of t he capt ur ed m easurem ent s;
•ESC: once t he MENU has been opened with t he D ATA+ UN I T keys, the CLR key
will allow to cancel the param eters set using the and arrows.
The DATA key is used for the following funct ions:
•DATA: during norm al m easurem ent, by pressing t his key once t he m axim um
( MAX) value of t he m easurem ent s capt ur ed by t he probe connect ed t o t he
inst rum ent is displayed, updat ing it w it h t he acquisit ion of new sam ples;
- by pressing t his key again the m inim um ( MI N) value is displayed;
- by pressing t his key a t hird t im e t he average ( AVG) v alue is display ed.
The acquisit ion frequency is once a second.
The MAX, MI N and AVG values rem ain in t he m em ory until t he inst rum ent is on,
ev en aft er exit ing t he DATA display funct ion. When t he inst rum ent is off, t he
previously m em orized data are cleared. Upon turning on, t he inst rum ent
autom atically st art s m em orizing the MAX, MI N and AVG values.
To reset the previous values and st art wit h a new measurem ent session, press
CLR unt il t he FUNC_ CLRD m essage appears.
•EN TER: once t he MENU has been opened with the D ATA+ UN I T keys, t he DATA
key will perform the ENTER funct ion and t he MENU can be browsed and the
displayed param et er confirm ed.
The H OLD key is used for t he following funct ions:
•HOLD: by pressing t his key t he current m easurem ent updat e is st opped and t he
"HOLD" m essage will appear in the upper left -hand corner of the display. To return
t o t he current m easurem ent , press t he key again.
D ATA/ EN TER k ey
HOLD/ 
D isa blin g of t he a ut om a t ic t u rnin g off
CLR/ ESC k e y

HD2301 - 8 - V1.7
•: once t he MENU has been opened wit h the D ATA+ U N I T keys, t he key will
allow t o increase t he value of the select ed param et er.
Pressed toget her with t he ON / OFF key, during turn on, t he Aut oPowerOff funct ion is
disabled (see t he descript ion of t he ON/ OFF key).
The UN I T key is used for the following functions:
•UN I T: by pr essing t his key t he unit of m easurem ent of t he m ain input quant it y is
select ed: t he unit of m easurem ent will appear in t he upper par t of t he display; t he
m easured value will be displayed in t he cent ral line. By repeat edly pressing t he
UN I Tkey, t he desired unit of m easurem ent can be select ed bet ween t he
follow ing:
1. % RH % of relat ive hum idit y
2. g/ m 3Gram s of vapour in a cubic m eter of dry air
3. hPA Part ial vapour pr essur e ( hPa)
4. Td Dew point ( ° C or ° F)
By now pressing UNI T, t he % RH unit of m easurem ent is displayed again in t he
com m ent line and, sim ult aneously, t he unit of t em perat ure m easurem ent blinks.
Use the and arrows, if you w ish t o change t he t em perature display from
degrees Celsius ( ° C) to degrees Fahreneit ( ° F), or vice-versa. Confirm by pressing
the UNI T key or wait for the unit of m easurem ent t o st op blinking ( about 15
seconds t im eout ) .
•M EN U : in the m enu t wo it em s can be set :
1. Probe t ype
2. Probe ca librat ion
- t he m enu is opened by pressing sim ult aneously D ATA+ U N I T: t he first it em of t he
inst rum ent program m ing m enu will appear;
- use t he and arrows ( r espect ively locat ed above t he HOLD and REL keys) t o
m odify t he display ed value;
- press D ATA/ ENTER to confir m t he m odification and go onto the next it em ;
- press CLR/ ESC to cancel t he m odificat ion;
- to e x it t he m enu, press t he U N I T/ M EN U key again.
The " REL" key is used for the following funct ions:
•REL: it displays t he difference bet ween t he current value and t hat m easured on
pressing the key. The "REL" m essage is displayed on t he left . To ret urn t o t he
norm al m easurem ent , press t he key again.
•: once the MENU has been opened wit h t he D ATA+ UN I T keys, t he key will
allow t o decrease t he value of t he select ed param eter .
REL/ key
UN I T/ M EN U

HD2301 - 9 - V1.7
THE PROGRAM M I N G M EN U
To access t o t he m enu press sim ult aneously the following keys:
The it em s t o be set are list ed in t his order:
1 . Pr obe t ype :the "PRBE_ TYPE" m essage is displayed in t he com m ent line. The
m ain line in t he cent er of t he display shows t he t ype of probe connect ed t o t he
inst rum ent. The following probes can be connect ed t o t he input :
•hum idit y/ t em perat ure com bined probes wit h " Pt100" sensor com plet e w it h
SI CRAM m odule
•t em perat ure probes " Pt100" com plet e wit h SI CRAM m odule
•direct 4 w ir e "Pt 100" probes com plet e wit h TP47 m odule
•2 or 4 wire " Pt 1000" probes com plet e wit h TP47 m odule
N OTE: The probes fit ted w it h SI CRAM m odule are autom at ically det ect ed by t he
inst rum ent upon t urning on. The type of probe is configured by t he inst rum ent and
cannot be m odified by t he user.
I f the direct 4 wire "Pt100" probes and the " Pt 1000" pr obes that are not
m anufact ured by Delta OHM are connect ed t o the inst rum ent , t he
N O_ PRBE_ SER_ NUM m essage is displayed. I n t his case t he probe t ype m ust be
ent ered m anually by t he user:
•use t he and ar row s ( respect ively locat ed above t he HOLD and REL keys)
to m odify t he type of probe;
•press D ATA/ EN TER t o confir m t he m odificat ion and go ont o t he next it em ;
•press CLR/ ESC to cance l t he m odificat ion;
•to e x it t he m enu, press t he UN I T/ M EN U key again.
2 . Use r calibr a t ion procedure of th e com bine d h um id it y / t e m p er at ure
probe: t he probes are calibrated in our laboratory at 23 ° C at t he relat iv e
hum idit y point s of 75% RH, 33% RH and 11.4% RH. On request , t he probes
can be checked at different isot herm s.
For t h e Ca librat ion se que nce , se e par agr a ph ‘Ca libr at ion of t he com bined
hum idit y/ t e m peratu r e probe’ a t page 1 1 .

HD2301 - 10 - V1.7
PROBES AN D M EASUREM EN TS
The inst rum ent HD2 3 0 1 .0 works by using com bined hum idit y/ t em perat ur e probes
( tem perat ure with a Pt 100 sensor) and wit h t em perat ure only probes w it h 4 w ir e
Pt 100, or 2 or 4 wire Pt 1000.
The com bined hum idity/ t em perat ure probes are fit t ed w it h SI CRAM m odule t hat act s
as an interface between the sensor on t he probe and t he inst rum ent . There is a
m icroprocessor circuit wit h a perm anent m em or y inside t he m odule t hat enables t he
inst rum ent to recognize t he type of probe connected and t o read its calibrat ion
inform at ion.
The Delt a OHM Pt1000 probes ar e aut om at ically det ect ed while t he dir ect 4 wir e Pt 100
t em perat ure probe is not aut om at ically detect ed by t he inst rum ent and m ust be set
up in the Pr obe t y pe m enu it em ( please see the m enu descript ion on prev ious
chapt er) .
The probe is detect ed durin g turn on, and this cannot be perform e d w hen the
in st r um e nt is a lr e ady on, t h e refor e if a p rob e is connect ed and t he
instrum ent is on, it is necessary to turn it off and on.
MEASU REM EN T O F RELATI VE H UM I DI TY
The hum idit y probes are "hum idity and tem perat ure" com bined pr obes:
•t he hum idit y sensor is a capacit at iv e t ype sensor ;
•the t em perat ure sensor is a Pt 100.
The inst rum ent m easures relat ive hum idit y % RH and t em perat ur e, and st ar t ing fr om
t he fixed barom et ric pressure value of 1013.25 m bar it calculates t he following
result ing quant it ies:
1. g/ m 3gram s of vapour in a cubic m eter of dry air
2. hPa Part ial vapour pressure ( hPa)
3. Td Dew point ( ° C or ° F)
PERFORM I N G TH E M EASUREM EN T
To perform t he m easurem ent , proceed as follow s:
1. introduce the probe in the area of whose param eters you wish t o m easure.
Ca u t ion!Keep the probe far from elem ents that m ight interfere wit h m easurem ent
such as: heat or sources of cooling, walls, air-st ream s, et c
Avoid t em pe r a t ure drops that m igh t ca u se condensation.
2. a reading taken when no heat drop occurs is pract ically im m ediat e;
N OTE: in condit ions involv in g he a t drops, it is necessary t o wait until the probes and
their housing have reached a therm al equilibrium in order to prevent heat irradiat ion
or absorpt ion on t he relative hum idit y sensor which would cause a fau lt y
m easure m en t .
3. since tem perat ure affect s relat ive hum idit y; m ove the probe like a fan in order to
speed t he response t im e in t he presence of heat drops.

HD2301 - 11 - V1.7
CALI BRATI ON OF TH E COM BI N ED HUM I D I TY/TEM PERATURE PROBE
Caution! To calibr at e the probes cor rect ly, a k nowledge of and abiding by t he
physical phenom ena on which the m easurem ent is based is fundam ental: t his is t he
reason why it is recom m ended t o abide by what is reported below carefully and only
to perform new calibrations if t echnically proficient.
The probes are calibrated in our laborat ory at 23 ° C at the point s of 75% RH, 33% RH
and 11.4% RH. On request , the probes can be checked at different isot herm s.
Th e ca librat ion of t h e t e m p er a t ure se nsor by t h e u se r is n ot r e qu ir ed: t he
sensor is ca libr at ed in t h e fa ct ory a nd t h e Ca lle ndar V an D use n par am e t er s
are r e corded in the SI CRAM m odu le.
I n or der t o ca libr a t e t h e in st r um e nt corre ct ly , it is very im por t an t f or t he
prob e a nd t h e sa t urat e d solut ions t o m a in t a in t h e sa m e t e m per at ur e a n d t hat
t his is a s st a ble as possible du rin g th e e nt ir e calibra t ion opera t ion.
Ca libration sequence:
1. Unscrew t he sensor prot ect ion on t he top of t he probe.
2. I n it s place screw t he bor ed cap wit h t he t hreaded r in g ver y well at t he base ( t her e
ar e t wo t ypes of t hread: M24x 1.5 and M12x 1, so use t he appropriat e one) .
3. Open the cap for the 75% RH saturated solution.
4. Should t here be any drops of solut ion inside t he m easuring cham ber, dr y t hem
wit h som e blot t ing paper.
5. I nsert the probe in t he container, m aking sure t he cap at the base is scr ewed
well. Th e m e a sur in g ch am ber m u st be close d per fe ct ly , other w ise it w ill
not get sa t urat ed: it is essent ial that no air passes through it .
6. W a it a t le ast 3 0 m in ut e s.
7. Press sim ult aneously t he D ATA and UN I T k eys t o open t he m enu;
8. Press D ATA/ EN TER t o reach t he second m enu item : t he m essage
"PROB_CAL_EXI T_OR_75_OR_3 3_OR_1 1" is show n in t he upper part of t he
display.
9. To proceed wit h t he calibr at ion:
•using the and arrows, select 7 5 % ( placed respect ively upper t he HOLD
and REL keys;
•confirm by pressing D ATA/ EN TER.
N OTE: to exit w ithout calibrat ing t he probe, use t he and arrows until
t he m essage "nonE" appears in t he cent ral display and press UN I T.
•t he r elat ive hum idit y read by t he probe is show n;
•if necessary, correct t he value of the sat urat ed solut ion against t he 75.0%
proposed by t he inst rum ent using t he arrows and .
The tem perat ure is t hat m easured by t he Pt100 or TC sensor.
To con fir m t h e calibr at ion p oin t :
•press D ATA/ EN TER. The inst rum ent r et urns t o t he calibrat ion m ain page
and displays " nonE". To proceed wit h anot her point , select it using the
arrows and confirm w it h UNI T.
10. To return to m easurem ent m ode, use the and arrows unt il t he m essage
"nonE" appears in t he central display and press U N I T.
11.Rem ove the probe from t he 75% RH container and close it im m ediat ely using its cap.

HD2301 - 12 - V1.7
Ca libr at ing t h e p oin ts at 3 3 % RH a n d 1 1 % RH
Repeat the points from 3) to 9) using t he saturated salts at 33% RH and 11%
RH.
When com pleted, unscrew t he ring with t he cap, and screw t he protect ion grid
back on t he sensor s. The calibrat ion is now com plet e.
I m por t ant not e s:
1 ) Do not let hands touch t he RH sensor.
2 ) The sensor base is in alum ina so it could easily break.
3 ) During the entire calibrat ion cycle keep t he tem perature as const ant as possible;
plast ic m at erials are poor t herm al conduct ors, t herefore som e tim e is needed for
them t o reach a therm al equilibrium .
4 ) I n case no satisfactory result s are obtained, check that:
•the sensor is not fault y, corroded or dirty,
•t he m easuring cham ber is perfect ly closed during calibrat ion,
•t he sat urat ed solut ions ar e not exhaust ed. A sat urat ed solut ion at 11% RH or
33% RH is exhaust ed when t here is no m ore salt inside bet ween t he t wo walls
but only a t hick liqu id: in t his case t he cham ber cannot reach it s sat urat ion
anym ore. For t he satur at ed solut ions at 75% RH, check that the salt is not dry
(crystallized) : in order to reach t he saturat ion, it needs to be wet.
5 ) St or age of t he sat urat ed solut ions: t he sat urat ed solut ions m ust be st ored in a
dark env ironm ent at a const ant t em perat ure of about 20 ° C w it h t he cont ainer well
closed inside a dry room .
Tem p
Lit hium
Magnesium
Sodium
° C
Chloride
Chloride
Chloride
0
11.23 ± 0.54
33.66 ± 0.33
75.51 ± 0.34
5
11.26 ± 0.47
33.60 ± 0.28
75.65 ± 0.27
10
11.29 ± 0.41
33.47 ± 0.24
75.67 ± 0.22
15
11.30 ± 0.35
33.30 ± 0.21
75.61 ± 0.18
20
11.31 ± 0.31
33.07 ± 0.18
75.47 ± 0.14
25
11.30 ± 0.27
32.78 ± 0.16
75.29 ± 0.12
30
11.28 ± 0.24
32.44 ± 0.14
75.09 ± 0.11
35
11.25 ± 0.22
32.05 ± 0.13
74.87 ± 0.12
40
11.21 ± 0.21
31.60 ± 0.13
74.68 ± 0.13
45
11.16 ± 0.21
31.10 ± 0.13
74.52 ± 0.16
50
11.10 ± 0.22
30.54 ± 0.14
74.43 ± 0.19
55
11.03 ± 0.23
29.93 ± 0.16
74.41 ± 0.24
60
10.95 ± 0.26
29.26 ± 0.18
74.50 ± 0.30
65
10.86 ± 0.29
28.54 ± 0.21
74.71 ± 0.37
70
10.75 ± 0.33
27.77 ± 0.25
75.06 ± 0.45
75
10.64 ± 0.38
26.94 ± 0.29
75.58 ± 0.55
80
10.51 ± 0.44
26.05 ± 0.34
76.29 ± 0.65
85
10.38 ± 0.51
25.11 ± 0.39
90
10.23 ± 0.59
24.12 ± 0.46
95
10.07 ± 0.67
23.07 ± 0.52
100
9.90 ± 0.77
21.97 ± 0.60

HD2301 - 13 - V1.7
DI RECT I N PUT I N TO Pt 100 AN D Pt 1 0 0 0 TEM PERATURE PROBES
The inst rum ent accept s the input of Plat inum tem perat ure probes wit h resistances of
100Ω( Pt100) and 1000Ω( Pt10 00) .
The Pt 100 ar e connect ed t o 4 w ir es, t he Pt 1000 t o 2 or 4 w ir es; t he ex cit at ion curr ent
was chosen in order t o m inim ize t he sensor self-heat ing effect s.
All probes w it h m odule are calibrated in t he fact ory, the 2 or 4 wir e probes wit h dir ect
input a r e check e d for confor m it y w it h cla ss A t ole r ance according t o norm
I EC751 - BS1904 - DI N43760.
The probes wit h SI CRAM m odule and t he Delt a Ohm Pt 1000 pr obes are det ect ed by
t he inst rum ent; t he m odel configur at ion is required for t he ot her probes ( please see
the descript ion of the Probe Type m enu it em on page 9) .
TEM PERATURE M EASUREM EN T
The tem perature m easurem ent by im m e r sion is carried out by inserting t he probe in
t he liquid for at least 60 m m ; t he sensor is housed in t he end part of t he probe.
I n t he tem perat ure m easurem ent by pe net rat ion t he probe tip m ust be inserted t o a
depth of at least 60 m m , the sensor is housed in the end part of t he probe.
N OTE: when m easuring t he t em perat ure on frozen blocks it is convenient to use a
m echanical t ool t o bore a cavit y in which t o insert t he t ip pr obe.
I n order t o perform a correct con t act m easurem ent , t he m easurem ent sur face m ust
be even and sm oot h, and t he probe m ust be perpendicular t o t he m easurem ent plane.
So a s t o obt ain t he cor re ct m e asu rem e nt , t he in se r t ion of a d rop of oil or
h eat -con duct ive past e betw een t he surface and the probe is useful ( do not
use w at er or solvents) . This m e t hod also im proves the r esponse tim e.
CON N ECTI N G TH E TP4 7 CON N ECTOR FOR TH E 4 - W I RE Pt 1 0 0 AN D 2OR 4 - W I RE
Pt 1000 PROBES
All probes produced by Delt a OHM are provided with a connect or.
The HD2 3 0 1 .0 Therm ohygrom et er also works w it h direct 4 wir e Pt 100, and Pt 1000
probes m anufact ured by other producers: for t he inst rum ent connect ion is prescribed
the TP4 7 connect or t o which t he probe's wires should be welded.
The inst ruct ions t o connect t he Plat inum probe t o t he TP47 m odule are provided
below.
The TP4 7 m odule is supplied com plete w it h fairlead and gasket for 5 m m m axim um
diam et er cables.
Do t he following to open t he m odule and connect a probe:
1. unscrew t he fairlead;
2. extract the gasket;
3. r em ove t he label using a cutt er;
4. unscr ew t he r ing on t he opposit e side as illust r at ed in t he figure:

HD2301 - 14 - V1.7
5. open t he two m odule shells: the printed circuit t o which the probe m ust be
connect ed is housed inside. On t he left there are the 1…4 points on which the
sensor wires m ust be welded. The JP1…JP4 j um pers are in t he cent er of the board.
These m ust be closed wit h a t in bead for som e type of sensors:
1
2
3
4
Pt100 3 wires
Pt1000
Ni1000
Not Used
Caution! Before welding, pass the probe cable through t he fairlead and gasket.
6. Weld t he w ires as shown in t he table:
Sensor
TP4 7 Boar d con ne ct ion
Jum per t o close
Pt 100 4
wires
4JP4
3JP3
1JP1
2 JP2
Pt100
4 wires
None
Pt 1000 2
wires
JP4
4
JP3
3
JP1
1
JP22
Pt1000
2
wires
JP2
Pt 1000 4
wires
JP2
Ensure the welds are clean and perfect .
7. Once the welding operation is com plete, close the t wo shells;

HD2301 - 15 - V1.7
8. I nsert t he gask et in t he m odule;
9. Screw t he fairlead and t he ring.
10.At the other end of t he m odule, enter t he ring wit h t he O-Ring as indicated in t he
pict ure.
11.Make sure t he cable is not t wist ed while you are screwing the fairlead. Now t he
probe is ready.
DI RECT CONNECTI ON OF 4W I RE Pt 100 SEN SORS
4 w ir e Pt 1 0 0 sensor s can be soldered
dir ect ly t o t he pins of t he f ly ing fem ale
connect or wit hout m aking use of t he
TP47 board. The 4 wires of t he Pt 100
sensors have to be soldered as
indicated in the figure on t he left. I n
order t o use this t y pe of probe it is
necessary t o set up the m enu it em
“ Probe Ty pe” , as described at page 9.
The P100 probe is recognized upon
t urning on the inst rum ent : connect t he
probe when t he inst rum ent is sw it ched
off and t hen t urn it on.
Sensor
Direct soldering to the connector
Pt 100 4
wires
View of t he solder ing side
of t he fly ing fem ale connect or

HD2301 - 16 - V1.7
W ARN I N GS
1. Probes are not insulat ed fr om t heir external casing; be very careful not t o com e
int o contact w it h live part s ( above 48V) . This could be ext rem ely
dangerous for t he inst rum ent as well as for the operator, who could be
elect rocuted.
2. Do not expose t he probes to gases or liquids that could corrode the m aterial of the
sensor or t he probe itself. Clean the probe carefully aft er each m easurem ent .
3. Do not bend the probe connect ors or force them upward or downward.
4. Do not bend or for ce t he contact s w hen insert ing t he pr obe connect or int o t he
instrum ent.
5. Do not bend, deform or drop t he probes, as t his could cause irreparable dam age.
6. Always select the m ost suitable probe for your applicat ion.
7. Do not use t he t em perature probes in presence of corrosive gases or liquids. The
sensor cont ainer is m ade of AI SI 316 st ainless st eel, while t he cont act probe
cont ainer is m ade from AI SI 316 st ainless steel plus silver. Avoid contact between
t he pr obe surface and any st icky surface or product t hat could cor rode or dam age
it .
8. Above 400° C and below –40° C, avoid violent blows or t herm al shock s t o Plat inum
t em perat ure probes as t his could cause irreparable dam age.
9. To obt ain reliable m easurem ents, t em perat ure variat ions t hat are t oo rapid m ust
be avoided.
10.Tem perat ure probes for surface m easurem ent s ( cont act probes) m ust be held
perpendicular against t he surface. Apply oil or heat-conduct ive paste between t he
sur face and t he pr obe in order t o im pr ove cont act and r educe r eading t im e.
Whatever you do, do not use wat er or solvent for t his purpose. A contact
m easurem ent is always very hard t o perform . I t has high levels of uncertainty and
depends on t he ability of the operat or.
11.Tem perat ure m easurem ent s on non-m et al surfaces usually require a great deal of
t im e due to the low heat conduct ivity of non-m et al m at erials.
12.Avoid t aking m easur em ent s in presence of high frequency sour ces, m icrowave
ovens or lar ge m agnetic fields; result s m ay not be very reliable.
13.Clean the probe carefully after use.
14.The inst rum ent is wat er resist ant and I P67, but should not be im m er sed in water.
The probe connect or s m ust be fitt ed with sealing gasket s. Should t he inst rum ent
fall int o t he w at er , check for any w at er infiltrat ion. Gent ly handle t he inst rum ent in
such a way as t o prevent any water infilt rat ion from t he connect ors' side.

HD2301 - 17 - V1.7
I N STRUMEN T SI GNALS AN D FAULTS
The follow ing t able list s all error indicat ions and inform at ion displayed by t he
inst rum ent and supplied to the user in different operating sit uat ions:
I ndicazione a displa y
Spie ga zione
- - -
This appears in t he display cent r al line w hen a t em perat ure only
pr obe is conn ect ed. I n t he low er line t h e t em p er at u re is show n
cor rect ly.
PRBE_ TYPE
Ty pe of p robe connect ed.
BATT TOO LOW
CH N G N O W
I ndicat ion of insufficient bat ter y charge appearing on t urning
on. The instrum ent issues a long beep and turns off. Replace
t he bat t er ies.
CAL
LOST
Pr ogram er r or : it appear s aft er t ur nin g on for a few seconds.
Contact t he inst rum ent's supplier.
CAL_ _ 1 1 _ UP D OW N Calibration at 11%
RH, use t h e ar row s t o cor rect t he v alu e
proposed.
CAL_ _ 3 3 _ UP D OW N Calibration at 33%
RH, use t h e ar row s t o cor rect t he v alu e
proposed.
CAL_ _ 7 5 _ UP D OW N
Calibration at 75% RH, use t he ar row s t o cor rect t he v alu e
proposed.
ERR
This appears if t he pr obe has already been det ect ed by t he
inst rum ent, but is disconnect ed. At t he sam e
t im e an
int erm it tent beep is issued.
FUN C CLRD
Max, m in and average values clear ed
NEW PROBE DET
This m essage appear s w hen a pr ob e is in ser t ed int o a
funct ioning inst rum ent. Turn t he inst rum ent off and t hen back
on again.
N O_ PRBE_ SER_ N UM The connect ed pr obe's ser ial nu m ber is absen t .
nonE No select ion.
OVER
Measu rem en t ov er flow : indicat es t hat t he pr obe is m easu ring a
value exceeding t he m easuring range.
PLS_ EX I T > > > FUN C
RES_ FOR_ FACT ONLY
Please exit using ESC > > > f unct ion r eser ved t o fact or y
calibration.
PRBE_ SER # # # # # # # # Serial num ber # # # # # # # # of t he connect ed probe.
PROB
ERR
A
probe w it h SI CRAM m odule has been in sert ed w hen not
adm issible for t h at specific inst r um ent .
PROB COMM LOST
This appears if t he probe has already been det ect ed by t he
inst rum ent, but is disconnect ed. At t he sam e tim e an
int erm it tent beep is issued.
PROB_ CAL_ EXI T_ OR_ 7
5 _ OR_ 3 3 _ OR_ 1 1
Probe calibration - exit or select 75, 33 or 11% RH.
SYS
ERR
#
I n st r um en t m anagem ent pr ogram er ror . Cont act t he in st rum en t 's
supplie
r an d com m u nicat e t he num er ic cod e # r ep or t ed by t h e
display.

HD2301 - 18 - V1.7
LOW BATTERY W ARN I N G AN D BATTERY REPLACEM EN T
The batt ery sym bol
on the display const antly shows the batt ery charge st at us. To the extent t hat batt eries
have dischar ged, t he sym bol "em pt ies" . When t he charge decr eases st ill furt her it
starts blinking.
I n this case, bat t eries should be replaced as soon as possible.
I f you cont inue to use it , the inst rum ent can no longer ensure correct m easurement.
The m em ory dat a are m aintained.
I f t h e bat t er y ch arge le ve l is in su fficie nt , t he follow in g m e ssa ge a ppe a rs
w hen you turn the in st rum ent on :
BATT TOO LOW
CH N G N OW
The inst rum ent issues a long beep and t urns off. I n t his case, repla ce t he
ba t teries in order to turn the inst r um ent back on.
To replace the batt eries, proceed as follows:
1. sw it ch t he inst rum ent off;
2. unscrew the batt ery cover counter clockwise;
3. r eplace t he bat t er ies ( 3 1.5V alk aline bat teries - t ype AA) ;
4. screw the cover on clockwise.
Malfunct ioning upon turnin g on after bat t e ry r eplace m e nt
After replacing t he bat teries, the inst rum ent m ay not rest art correctly; in t his case,
repeat the operat ion.
After disconnect ing t he batt eries, wait a few m inutes in order t o allow circuit
condensers to discharge com pletely; t hen r einsert t he bat teries.
WARN I N G ABOU T BATTERY USE
•Bat teries should be rem oved when t he instrum ent is not used for an extended
t im e.
•Flat bat t eries m ust be replaced im m ediately.
•Avoid batt er ies leaking.
•Always use good qualit y leakproof alkaline bat teries. Som et im es on the m arket ,
it is possible t o find new bat t eries w it h an insufficient charge capacity.

HD2301 - 19 - V1.7
I N STRUM EN T STORAGE
I nst rum ent st orage condit ions:
•Tem perat ure: -25...+ 65 ° C.
•Hum idity: less t han 90% RH wit hout condensat ion.
•Do not st ore t he inst rum ent in places where:
•hum idit y is high;
•the inst rum ent m ay be exposed to direct sunlight;
•t he inst rum ent m ay be exposed t o a source of high tem perature;
•the inst rum ent m ay be exposed t o st rong vibrations;
•t he inst rum ent m ay be exposed t o st eam , salt or any corrosive gas.
The inst rum ent case is m ade of ABS plast ic: do not use any incom pat ible solvent for
cleaning.

HD2301 - 20 - V1.7
N OTES ABOUT W ORKI N G AN D OPERATI VE SAFETY
Au t hor ized u se
The t echnical specifications as given in chapt er TECHNI CAL CHARACTERI STI CS m ust
be observed. Only t he operat ion and running of t he m easuring inst rum ent according
t o t he inst ruct ions giv en in t his operat ing m anual is aut horized. Any ot her use is
considered unauthorized.
Ge ne ra l sa fe t y inst ruct ions
This m easuring syst em is const ruct ed and test ed in com pliance w it h t he EN 61010-1
safet y regulat ions for elect ronic m easuring inst rum ents. I t left t he fact ory in a safe
and secure t echnical condit ion.
The sm oot h funct ioning and operat ional safet y of t he m easuring syst em can only be
guaranteed if t he generally applicable safet y m easures and t he specific safet y
inst ruct ions in t his operat ing m anual are followed during operat ion.
The sm oot h funct ioning and operat ional safet y of t he inst r um ent can only be
guaranteed under t he env ironm ent al and elect r ical oper at in g condit ions t hat ar e in
specified in chapt er TECHNI CAL CHARACTERI STI CS.
Do not use or st ore the product in places such as list ed below:
•Rapid changes in am bient t em perat ure which m ay cause condensation.
•Corrosive or inflam m able gases.
•Dir ect v ibr at ion or shock t o t he inst rum ent .
•Excessive induct ion noise, st at ic elect r icit y, m agnet ic fields or noise.
I f t he m easuring sy st em w as t ransport ed from a cold environm ent t o a warm
environm ent, the form at ion of condensate can im pair the funct ioning of the m easuring
syst em . I n t his event, wait unt il t he t em perat ure of t he m easuring syst em reaches
room t em perature before putt ing the m easuring syst em back int o operation.
Obligations of t he purchaser
The purchaser of t his m easuring syst em m ust ensure t hat t he following laws and
guidelines are observed when using dangerous subst ances:
EEC dir ect ives for prot ect iv e labour legislat ion
Nat ional pr ot ect ive labour legislat ion
Safet y r egulat ions